Cover Image
close this bookEnergy and Protein requirements, Proceedings of an IDECG workshop, November 1994, London, UK, Supplement of the European Journal of Clinical Nutrition (International Dietary Energy Consultative Group - IDECG, 1994, 198 pages)
close this folderEnergy requirements and dietary energy recommendations for children and adolescents 1 to 18 years old
View the document(introductory text...)
View the documentIntroduction
View the documentTotal daily energy expenditure (TEE)
View the documentEstimates of basal metabolic rate to calculate total energy expenditure
View the documentTime allocation to different activities
View the documentPhysical activity levels of children and adolescents
View the documentDietary energy intake
View the documentGeneral conclusions and recommendations
View the documentReferences
View the documentDiscussion

(introductory text...)

B Torun1, PSW Davies2, MBE Livingstone3, M Paolisso4, R Sackett5, GB Spurr6 (with contribution from MPE de Guzman7)

1 Health and Nutrition Unit, Institute of Nutrition of Central America and Panama, Apartado Postal 1188, Guatemala, Guatemala;
2 Infant and Child Nutrition Group, MRC Dunn Nutrition Unit, Cambridge CB4 IXJ, UK;
3 Department of Biological and Biomedical Science, University of Ulster, Coleraine, Northern Ireland BT52 ISA, UK;
4 International Center for Research on Women, Washington, DC 20036, USA;
5 Departments of Anthropology, Memphis State University, Memphis, TN 38152, USA;
6 Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53295, USA;
7 Department of Science and Technology, Food and Nutrition Research Institute, Metro Manila 1604, Philippines

Descriptors: energy requirements, energy expenditure, physical activity, dietary energy, children, adolescents, time allocation

Introduction

In 1981, a group of experts was convened by FAO, WHO and UNU to evaluate the energy and protein requirements of humans, and to make appropriate dietary recommendations. Several key concepts related to energy were asserted in their report (FAO/WHO/ UNU, 1985), which included the following:

· The energy requirement is the amount of dietary energy needed to maintain health, growth, and an 'appropriate' level of physical activity.
· 'Appropriate' physical activity includes those activities that an individual must perform to survive in his/her social environment (occupational activities), and to pursue his/her physical, intellectual and social desires and wellbeing (discretionary activities). For children, this should allow the exploration of the surroundings and the interaction with other children and adults.
· Energy needs are determined by energy expenditure. Therefore, estimates of requirements should be based on measurements of energy expenditure and, for children, an additional allowance for growth.
· Energy requirements can be calculated as multiples of basal metabolic rate (BMR). In the absence of direct measurements, BMR can be estimated with mathematical equations derived from published metabolic data.

However, very little information was available on total energy expenditure (TEE) of children. Consequently, estimates of energy requirements for 1-10 year old children were based on the reported energy intakes of healthy, well nourished children, with the tacit assumption that they represented habitual intakes. These estimated requirements were derived from an extensive review of published dietary intake data on approximately 6500 children, mostly from developed countries (Ferro-Luzzi & Durnin, 1981).

Correspondence to: Dr B Torun.
Note: Participation in the preparation of this document does not imply that all contributors agree with all of the conclusions and recommendations

The FAO/WHO/UNU Expert Committee was also concerned about a perceived secular trend towards sedentary lifestyles in developed countries. Therefore, it was felt prudent to increase by 5% the reported energy intakes of children between 1 and 10 years of age to accommodate a desirable level of physical activity.

After 10 years of age, estimates of energy expenditure expressed as multiples of BMR provided the basis to calculate energy requirements, rather than energy intake data. BMR for boys and girls of a given age and weight were predicted with the mathematical equations derived by Schofield (FAO/WHO/UNU, 1985; Schofield, 1985), and the additional energy expended during the day was calculated based on the assumed energy cost of activities performed by children and adolescents in developed countries. The extra allowance for growth was assumed to be 5.6 kcal (23.4 kJ) per gram of expected weight gain. This corresponded to about 3% of the daily energy requirement at one year of age, with a gradual decrease to about 1% at 15 years.

In deriving these estimates of energy requirements for children and adolescents the FAO/WHO/UNU Expert Committee acknowledged that they exceeded the dietary energy intakes reported for these ages. It was considered that the low intakes reflected an undesirably low level of physical activity, and that dietary recommendations should include enough energy to allow an increase in activity. It should be noted that the spontaneous activity of children and hence energy expenditure can be restricted by energy intake as demonstrated by studies in Guatemala (Town, 1990b).

In the years that followed the 1981 FAO/WHO/ UNU Expert Consultation, more has been learned about the energy expenditure of children and adolescents and of the way they distribute their time in activities that demand different levels of energy expenditure, largely due to the application of the doubly-labeled water method, the improved technology and validation of heart-rate monitoring techniques, and the analysis of physiological, nutritional and anthropological studies (Schürch & Scrimshaw, 1990). Additional information on food intake and on basal and resting metabolic rates have also allowed a better appraisal of the calculation and validity of energy requirements between 1 and 18 years of age.

This document presents a critical review of that knowledge and makes recommendations for consideration by the group of experts that will revise the 1985 FAO/WHO/UNU report.

Total daily energy expenditure (TEE)

Three types of methods have been used to calculate total daily energy expenditure of free-living children and adolescents. Their advantages and limitations have been reviewed by several authors (e.g. Torun, 1984; Durnin, 1990).

(1) Doubly-labeled water. This method has two components: (a) Administration of a marker dose of 2H and 18O, and measurement of the disappearance of the isotope from the body after several days and (b) Calculation of the food quotient or estimation of the average respiratory quotient during that period of time.

The doubly-labeled water is the most accurate of the three methods. However, there are still some doubts about the appropriateness of the assumptions used for the calculation of energy expenditure. Moreover, the number of children so far studied is very small and restricted to few geographical areas due to the high cost of the isotopes and their analysis. Furthermore, it does not provide information on the patterns of physical activity throughout the day.

(2) Heart rate monitoring. This method has three components. (a) Measurement of heart rate while resting and measurement or estimation of the resting and basal metabolic rates. (b) Determination of the relationship between heart rate and oxygen consumption (or energy expenditure) with light, moderate and moderately heavy workloads. This relationship varies among individuals and must be established for every person who will be studied. (c) Minute-by-minute recording of heart rate.

Table 1 Comparison of total daily energy expenditures (MJ/d) measured with two different heart rate monitoring techniques (three-way analysis of variance with unweighted averages)

Minute-by-minute heart rate method (Spurr and Reina, 1988a)

Age (y)

n

Control children
mean

s.d.

n

Mildly malnourished
mean

s.d.

6-8

24

6.6

1.6

21

5.1

1.0

10-12

18

8.4

2.3

23

7.8

2.1

14-16

20

12.1

2.7

26

10.6

2.5

Daytime heart rate accumulation method (Spurr et al., 1986)

Age (y)

n

Control children
mean

s.d.

n

Mildly malnourished
mean

s.d.

6-8

12

6.4

1.1

9

6.3

0.7

10-12

20

9.2

1.8

19

8.0

1.8

14-16

12

11.5

2.0

16

10.2

2.1

Source

F ratio

Probability

A (Age)

109.283

<0.001

B (Nutritional status)

14.463

<0.001

C (Method)

0.413

0.521

A*B (Age*Nutrition)

0.403

0.668

A*C (Age*Method)

1.495

0.226

B*C (Method*Nutrition)

0.462

0.498

A*B*C (Age*Nutrition*Method)

1.054

0.350

Earlier studies used recorders that accumulated all heart beats over some period of time. Average heart rate over 24 h gave unacceptable results due to the poor relationship between heart rate and oxygen consumption at resting and sedentary levels of energy expenditure. However, the method yields acceptable results when the average heart rate is calculated for the period of time when children are awake, and energy expenditure calculated for the remainder of the 24 h from the resting and basal metabolic rates. As shown in Table 1, an analysis of studies by Spurr and collaborators (Spurr et al, 1986; Spurr and Reina, 1988a) indicated that the results with this heart rate accumulation method did not differ from those obtained in similar children with the minute-by-minute rate recording method.

The heart rate monitoring method has been validated with whole body calorimetry and doubly-labeled water. Comparisons varied on an individual basis, but the mean values for groups of individuals were similar to the other methods (Spurr et al, 1988; Ceesay et al, 1989; Livingstone et al, 1990a, 1992a; Emons et al, 1992). Thus, heart rate monitoring can be used to estimate the energy expenditure of groups of children. Minute-by-minute recording also allows, examining the time allocated to different intensities of physical effort.

(3) Time-motion or activity diary techniques. These have two components: (a) assessment of time allocation, which has been explored by direct observations with different timing techniques, by activity records or diaries kept by the subjects or caretakers of young children, and by recall interviews with subjects or caretakers and (b) energy costs of the activities that are observed or recorded, measured by indirect calorimetry or estimated from published values. It should be borne in mind that energy costs of activities published for adults do not apply to children under 15 (Town, 1983, 1990a). Many of the results published with the time motion or diary techniques are questionable due to the inaccuracies inherent in methods based on reporting and in the application of energy cost of activities of adults to calculate energy expenditure of children.

We have based this review and our conclusions on TEE on studies with doubly-labeled water or with appropriate techniques of heart rate monitoring. Some estimates of energy expenditure with time motion/diary techniques were selected as examples to examine the conclusions based on the other two methods.

Another relatively simple way to estimate total daily energy expenditure (TEE), and therefore requirements, of adults was proposed by the 1985 FAO/WHO/UNU Expert Consultation. Sleeping, occupational, discretional, health-promoting and other miscellaneous activities were assigned an energy cost, expressed as multiples of basal metabolic rate ( × BMR) or physical activity level (PAL)1. A factorial calculation accounting for the time allotted to each of those activities allowed the estimation of the mean PAL in 24 h. For populations engaged in occupational activities of different intensities. TEEs of 1.55, 1.78 and 2.10 × BMR were proposed for men with light, moderate and heavy occupational activities, respectively (FAO/WHO/UNU, 1985). The corresponding factors suggested for women were 1.56, 1.64 and 1.82.

We suggest that a similar approach be used to estimate TEE of groups of children and adolescents with different lifestyles. PAL factors are proposed for those estimates in another section of this document ('Physical activity levels of children and adolescents').

Studies with doubly-labeled water

The doubly-labeled water technique is almost 40 years old, but there are still relatively few data on total energy expenditure in children, due primarily to cost. Until the mid 1970s the cost of the stable isotopes (2H and 18O) involved in the technique was restrictive. Since that time advances in technology, notably the development of highly precise isotope mass ratio spectrometers, made it possible to administer significantly less isotope, thus reducing the cost to a more manageable figure. Unfortunately, the cost of isotopes began to rise steeply in 1990 and once again fewer studies are being undertaken.

Studies that allow consideration of TEE and dietary recommendations have been done with well-nourished children and adolescents in urban centers of the United Kingdom (Prentice et al, 1988; Davies et al, 1991, 1994), Holland (Saris et al, 1989; Emons et al, 1992) and the United States (Bandini et al, 1990b; Goran et al, 1993; Fontvieille et al, 1993; Wong, 1994). Table 2 shows their age span and TEE expressed per day, per unit of body weight and PAL.

Figure 1 compares the data from Table 2, expressed as kcal/kg/day, with the FAO/WHO/UNU 1985 recommendations, with and without the allowance for growth. The values for energy expenditure shown in the table and figure do not include the small proportion of energy that should be retained for growth (between 1 and 3%, depending on age).

Current dietary energy recommendations are about 20% higher than energy expenditure of children under 7 years of age in industrialized societies. From 7 years onwards, current recommendations coincide reasonably well with the data from doubly-labeled water studies, although boys throughout adolescence and girls around puberty seem to require 5-15% more dietary energy.

1 Total energy expenditure expressed as × BMR has been considered to reflect an individual's or population's physical activity level (PAL). This term has appeared with increasing frequency in the scientific literature. Thus, we will use it as synonym of × BMR.


FIGURE 1a
Total energy expenditure estimated with doubly labeled water: boys.


FIGURE 1b
Total energy expenditure estimated with doubly labeled water: girls.

Within each sex, the PALs in Table 2 show a trend towards uniformity among children between 1 and 5, 6 and 13, and 14 and more years of age. Therefore, the mean PAL values for those three age groups were calculated (Table 3). Since the studies had similar sample sizes within each age group, calculations of the mean PAL weighted for the number of children in each study gave similar results. Measured BMRs were used for calculations in three studies and BMR estimates with Schofield's equations in all others.

On the average, there were no gender differences at 1-5 and 6-13 years. Boys seemed to have higher PAL than girls after that age, but this observation was based on only three data sets from two studies (Bandini et al, 1990b; Davies et al, 1991). It should also be noted that if PALs were calculated with the equations published by FAO/WHO/UNU (1985) instead of those modified later by Schofield (1985), they would be somewhat lower for girls 1-5 and 6-13 years old than for boys of the same age ranges (1.39 vs 1.47 and 1.74 vs 1.81, respectively).

It should be kept in mind that the values shown in Tables 2 and 3 correspond to studies in a small number of well nourished children with adequate growth patterns, living in societies where food and health services are continuously and readily available.

Table 2 Groups of children, classified by sex and age, whose total daily energy expenditure has been estimated by the doubly labeled water method (does not include 1-3%, depending on age, that should be retained for growth)



Total energy expenditure


Agea (y)

n

Weight (kg)

(kcal/d)

(kcal/kg/d)

PALb

Reference

Boys

1-1.9

8c



83.0d


Prentice et al (1988)

1.5-2.49

11

12.6 ± 1.4e

1075 ± 305

85.8 ± 26.0

1.49

Davies et al (1994)

2-2.9

6c



81.0d


Prentice et al (1988)

2.5-3.49

15

15.0 ± 1.7

1207 ± 181

81.5 ± 15.2

1.41

Davies et al (1994)

3-4

13

15.5

1300

83.9 ± 11.5

1.52

Davies et al (1991)

3-4.49

16

16.9 ± 2.3

1301 ± 211

78.2 ± 14.5

1.47

Davies et al (1994)

4-6

16

20.3 ± 4.3

1438 ± 271

71.5 ± 8.0

1.49

Goran et al, (1993)

5.4 ± 0.3

15

21.1 ± 3.9

1415 ± 252

67.1

1.44

Fontvieille et al (1993)






(1.36)


5-6

12

18.9

1654

87.5 ± 10.0

1.77

Davies et al (1991)

7-8

10

24.6

1958

79.6 ± 9.1

1.84

Davies et al (1991)

9.3 ± 1.4

9

30.9 ± 4.3

2151

69.6

1.78

Saris et al (1989)






(1 77)


9-10

14

29.5

2180

73.9 ± 12.2

1.86

Davies et al (1991)

12-13

8

39.7

2334

58.8 ± 9.8

1.71

Davies et al (1991)

14.5 ± 1.5

13

56.4 ± 10.2

3109 ± 506

56.3 ± 6.4

1.88

Bandini et al (1990b)






(1.79)


15-16

12

60.1

3233

53.8 ± 7.6

1.88

Davies et al (1991)

18-19

12

71.6

3437

48.0 ± 4.3

1.86

Davies et al (1991)

Girls

1-1.9

7c



83.0d


Prentice et al (1988)

1.5-2.49

12

13.0 ± 1.9

1062 ± 212

83.0 ± 19.5

1.46

Davies et al (1994)

2-2.9

6c



81.0d


Prentice et al (1988)

2.5-3.49

16

14.9 ± 1.1

1125 ± 211

75.8 ± 15.0

1.38

Davies et al (1994)

3-4

18

14.8

1150

77.7 ± 10.3

1.46

Davies et al (1991)

3.5-4.49

11

17 ± 2.0

1263 ± 237

74.2 ± 11.0

1.52

Davies et al (1994)

4 6

14

21.0 ± 4.7

1344 ± 314

63.5 ± 5.6

1.47

Goran et al (1993)

5.5 ± 0.4

13

18.9 ± 2.5

1318 ± 189

69.7

1.51

Fontvieille et al (1993)






(1.37)


5-6

16

18.5

1473

79.6 ± 10.5

1.71

Davies et al (1991)

7-8

15

26.0

1989

76.5 ± 17.7

1.96

Davies et al (1991)

8.1 ± 1.3

10

28.2 ± 2.6

1926

68.3

1.82

Saris et al (1989)






(1.69)


9-10

15

29.1

1816

62.4 ± 10.5

1.69

Davies et al (1991)

12-13

10

49.3

2569

52.1 ± 7.9

1.90

Davies et al (1991)

13.2 ± 1.8

9

43.3 ± 8.9

2321 ± 281

53.6

1.82

Wong, (1994)

14.3 ± 1.0

12

55.7 ± 9.4

2385 ± 446

43.9 ± 7.7

1.66

Bandini et al (1990b)






(1.69)


15-16

11

58.0

2453

42.3 ± 6.0

1.67

Davies et al (1991)

18-19

11

62.4

2533

40.6 ± 7.6

1.72

Davies et al (1991)

a Range or mean ± standard deviation.
b Physical Activity Level calculated using basal metabolic rates estimated with Schofield's equations (1985) (or, in parenthesis, measured experimentally).
c Assuming 50% of the children studied were boys and 50% girls.
d Assuming the same values for boys and girls.
e Mean ± s.d.

Table 3 Mean physical activity levels of children in Table 2 grouped by age and sex. (Total energy expenditure measured with doubly labeled water; BMR's were measured or estimated with Schofield's equations)

Age (y)

Boys

Girls

1-5

1.46 ± 0.06 (6)a

1.44 ± 0.06 (6)

6-13

1.79 ± 0.06 (5)

1.80 ± 0.12 (6)

14+

1.84 ± 0.05 (3)

1.69 ± 0.03 (3)

a Mean ± s.d. of mean values in Table 2. Number of data sets in parenthesis. Means weighted by the number of children in each study gave similar values.

Studies with heart rate monitoring

Studies to calculate TEE of children and adolescents through heart rate monitoring have also been done only in a few countries, but they include industrialized and developing societies. These studies were done with either daytime heart rate accumulation (Spady, 1980; Torun & Viteri, 1981a,b; Spurr et al, 1986; Spurr & Reina, 1987) or the minute-by-minute heart rate method (Spurr & Reina, 1988a,b, 1989a,b; Livingstone et al, 1992a; Emons et al, 1992; Torun et al, 1993; Ramirez & Torun, 1994). Table 4 shows their age span and results. All studies involved children living in urban centers. Those in Northern Ireland and Holland involved only between 3 and 6 children in each sex-and-age group, and those in Canada were clone with 11 boys and 10 girls. Most studies in Colombia and Guatemala involved 16-34 boys or girls in each age group (median sample size = 20).

Table 4 Groups of children, classified by sex and age, whose total daily energy expenditure was estimated by heart rate monitoring methods (does not include 1-3% energy, depending on age, that should be retained for growth)




Total energy expenditure






Age (y)

n

Weight
(kg)

(kcal/d)

(kcal/kg/d)

PALa

Country

Conditionc

Methodd

Source

Boys

2.5 ± 0.7

6

11.9 ± 1.0

1060

89.1 ± 9.0

1.56b

Guatemala

Stunted

Accum

Torun & Viteri (1981b)

3.1 ± 0.3

11

12.0 ± 0.8

901

74.8 ± 7.6

1.34

Guatemala

Stunted

Accum

Torun & Viteri (1981a)

6.8 ± 0.5

24

21.9 ± 1.6

1581 ± 374

72.3 ± 16.8

1.60

Colombia


M-M

Spurr & Reina (1988a)

7.0 ± 0.5

12

21.8 ± 1.4

1541 ± 255

70.2 ± 8.4

1.54b

Colombia


Accum

Spurr et al (1986)

7.0 ± 0.5

21

19.3 ± 1.7

1207 ± 243

62.7 ± 12.5

1.46

Colombia

Underweight

M-M

Spurr & Reina (1988a)

7.4 ± 0.7

9

19.4 ± 2.3

1502 ± 176

81.0 ± 9.7

1.59b

Colombia

Underweight

Accum

Spurr et al(1986)

7.5 ± 0.3

6

25.4 ± 6.6

1859 ± 388

74.4 ± 12.2

1.64

UK


M-M

Livingstone et al (1992a)

8.4

5

27.8

2414 ± 394

86.8 ± 14.2

2.13b

Holland


M-M

Emons et al(1992)

9.3 ± 0.2

5

30.2 ± 9.4

2119 ± 182

74.5 ± 17.7

1.88

UK


M-M

Livingstone et al (1992a)

9.4 ± 1.0

11

32.1 ± 4.4

2164 ± 199

66.4 ± 9.8

1.86

Canada


Accum

Spady (1980)

10.8 ± 0.5

34

33.3 ± 2.8

2051 ± 400

61.7 ± 13.0

1.75

Guatemala


M-M

Ramirez & Torun (1994)

10.9 ± 0.6

19

25.9 ± 2.6

1918 ± 425

73.6 ± 16.6

1.72b

Colombia

Underweight

Accum

Spurr et al (1986)

11.0 ± 0.6

20

32.4 ± 3.3

2209 ± 419

68.1 ± 12.7

1.79b

Colombia


Accum

Spurr et al (1986)

11.1 ± 0.6

14

33.1 ± 2.3

2009 ± 421

60.7 ± 12.7

1.67

Colombia


M-M

Spurr & Reina (1988b)

11.1 ± 0.6

23

27.2 ± 2.8

1823 ± 513

67.5 ± 17.2

1.74

Colombia

Underweight

M-M

Spurr & Reina (1988a)

11.1 ± 0.6

19

26.6 ± 3.2

1828 ± 378

68.7 ± 14.2

1.77

Colombia

Underweight

M-M

Spurr & Reina (1988b)

11.1 ± 0.5

34

28.8 ± 3.1

2015 ± 379

70.1 ± 11.5

1.83

Guatemala

Stunted

M-M

Ramirez & Torun (1994)

11.2 ± 0.5

18

33.3 ± 2.5

2020 ± 542

60.5 ± 15.2

1.74

Colombia


M-M

Spurr & Reina (1988a)

12.7 ± 0.3

5

43.8 ± 7.3

2624 ± 315

61.4 ± 12.7

1.76

UK


M-M

Livingstone et al (1992a)

14.6 ± 0.6

16

34.8 ± 5.1

2445 ± 493

71.4 ± 12.5

1.92

Colombia

Underweight

Accum

Spurr et al (1986)

14.7 ± 0.5

12

46.7 ± 3.5

2762 ± 480

58.4 ± 9.0

1.84

Colombia


Accum

Spurr et al (1986)

14.8 ± 0.6

20

49.9 ± 3.2

2896 ± 650

58.4 ± 14.4

1.94

Colombia


M-M

Spurr & Reina (1988a)

14.8 ± 0.4

26

38.9 ± 5.3

2556 ± 580

65.6 ± 13.7

1.93

Colombia

Underweight

M-M

Spurr & Reina (1988a)

15.4 ± 0.4

3

50.7 ± 6.4

2745 ± 33

54.7 ± 6.9

1.71

UK


M-M

Livingstone et al (1992a)

Girls

6.6 ± 0.5

21

21.4 ± 1.1

1386 ± 304

63.0 ± 11.5

1.53

Colombia


M-M

Spurr & Reina (1988a)

7.0 ± 0.5

16

18.2 ± 1.7

1244 ± 254

67.6 ± 13.5

1.40

Colombia

Underweight

M-M

Spurr & Reina (1988a)

7.8 ± 0.3

5

23.5 ± 2.5

1609 ± 260

68.3 ± 5.0

1.55

UK


M-M

Livingstone et al (1992a)

8.4

5

28.3

2079 ± 191

73.5 ± 6.8

1.96b

Holland


M-M

Emons et al (1992)

9.4 ± 0.5

4

33.4 ± 3.8

1729 ± 174

52.0 ± 5.2

1.63

UK


M-M

Livingstone et al (1992a)

9.4 ± 1.2

24

28.3 ± 3.4

1537 ± 340

55.2 ± 13.6

1.43

Colombia


Accum

Spurr & Reina (1987)

9.5 ± 0.8

10

31.6 ± 3 7

1716 ± 243

55.1 ± 11.6

1.52b

Canada


Accum

Spady (1980)

9.8 ± 1.0

20

23.7 ± 2.3

1640 ± 284

69.4 ± 10.3

1.70b

Colombia

Underweight

Accum

Spurr & Reina (1987)

10.8 ± 0.6

21

27.3 ± 4.0

1584 ± 369

55.1 ± 12.8

1.57

Colombia

Underweight

M-M

Spurr & Reina (1988a)

10.9 ± 0.7

11

34.2 ± 3.7

1611 ± 319

46.8 ± 8.9

1.45

Colombia


M-M

Spurr & Reina (1988a)

11.4 ± 0.5

23

29.2 ± 3.3

1867 ± 338

63.6 ± 11.6

1.72b

Guatemala

Stunted

M-M

Torun et al (1993)

11.8 ± 0.6

88e

31.1 ± 4.0

2013 ± 400

64.3 ± 11.8

1.81b

Guatemala

Stunted

M-M

Torun et al (1993)

12.2 ± 0.5

21

33.7 ± 4.4

2170 ± 441

64.5 ± 11.5

1.90b

Guatemala

Stunted

M-M

Torun et al (1993)

12.5 ± 0.4

5

45.1 ± 4.7

2232 ± 234

49.7 ± 5.4

1.60

UK


M-M

Livingstone et al (1992a)

14.9 ± 0.6

19

49.3 ± 2.7

1982 ± 452

41.7 ± 9.6

1.61

Colombia


M-M

Spurr & Reina (1988a)

15.2 ± 0.5

22

42.0 ± 4.1

1950 ± 585

48.6 ± 14.9

1.61

Colombia

Underweight

M-M

Spurr & Reina (1988a)

15.6 ± 0.4

3

55.4 ± 13.2

2365 ± 811

42.9 ± 12.3

1.88

UK


M-M

Livingstone et al (1992a)

a Physical Activity Level calculated using BMR measured by the investigators or estimated mathematically (b).
b PAL calculated using BMR estimated with Schofield's equations (1985).
c Stunted: > 1.5 s.d. below the NCHS median of height-for-age. Underweight: < 95% of weight-for-age and weight-for-height in comparison to Colombian children of upper socioeconomic groups (Rueda-Williamson et al, 1969). All others: adequate height and weight for age.
d Accum = heart rate accumulation during daytime, and BMR while sleeping; M - M = minute-by-minute recording.
e 22 girls measured longitudinally four times at 3-month intervals.

Table 5 Mean physical activity levels of children in Table 4 grouped by age, sex and height or weight. (Total energy expenditure estimated by heart rate monitoring; BMR's were measured or estimated with Schofield's equations)a


Boys

Girls

Age (years)

Adequate
wt and ht

Stunted or underweight

All

Adequate
wt and ht

Stunted or underweight

All

(A) Means of mean values in each studyb

2-3

-

1.45 (2)

-

-

-

-

6-13

1.72 ± 0.11 (10)b

1.68 ± 0.14 (6)

1.71 ± 0.12 (16)

1.53 ± 0.07 (7)

1.66 ± 0.19 (5)

1.58 ± 0.14 (12)

14+

1.83 ± 0.12 (3)

1.92 (2)

1.87 ± 0.10 (5)

1.74 (2)

1.61 (1)

1.70 ± 0.16 (3)

(B) Weighted meansc

2-3

-

1.42 (17)

-

-

-

-

6-13

1.65 (149)

1.71 (125)

1.68 (274)

1.50 (80)

1.67 (101)

1.60 (181)

14+

1.89 (35)

1.93 (42)

1.91 (77)

1.65 (22)

1.61 (22)

1.63 (44)

a Data of Emons et al (1992) excluded due to their unusually high PAL's.
b Mean ± s.d. of mean values in Table 4. Number of data sets in parenthesis.
c Weighted by the number of children in each study (in parenthesis)

PALs in Table 4 were calculated using measured BMR in most studies; estimates with Schofield's equations (1985) were used in only six of them. Table 5 shows the mean PALs for the same age groups as in Table 3. Although there were large differences in sample sizes (3-34), the means of the mean values in each study were within 5% of the mean values weighted for the number of children in every sex-and-age group.

All Canadian, Dutch and Irish children apparently had adequate weight and height. The Colombian children were from low and low-middle socioeconomic groups of Cali. They were classified as well nourished or as marginally malnourished or underweight when their weight-for-age and weight-for-height was above or below 95% of the Colombian standards for children of upper socioeconomic groups, respectively (Rueda-Williamson et al, 1969). Most Guatemalan children were from the lower socioeconomic groups of Guatemala City. While presently well nourished, they were stunted by more than 1.5 s.d. below the NCHS/WHO median of height-for-age. One group of Guatemalan boys (Ramirez and Torun, 1994) was from the middle socioeconomic class and they had adequate height and weight.

Figure 2 compares the data in Table 4, expressed as kcal/kg/day, with the FAO/WHO/UNU 1985 recommendations. Total energy expenditure per unit of body weight was greater among the stunted and underweight children. Since the FAO/WHO/UNU values were derived from data of well nourished, non-stunted children, Figure 3 shows only the values described in Table 4 for such children. They are combined with data from doubly-labeled water in Figure 4.

The higher energy expenditure per unit of body weight often observed in stunted and mildly malnourished children, compared with those of adequate height and weight (Tables 1 and 4), could be partly due to differences in body composition. If so, the differences in TEE would be expected to decrease or disappear when expressed as multiples of BMR (i.e. PAL units). Table 6 shows the PALs of 'normal' and stunted or mildly underweight individuals within the same community. In contrast with TEE per unit of body weight, there was no consistent difference in the PAL of children and adolescents with adequate height and weight, compared with their stunted or slightly underweight counterparts (Tables 5 and 6). This supports the explanation attributing differences to body composition.

However, the differences in TEE could also be related to the children's physical activity patterns. An examination of the minute-by-minute heart rate and its energy equivalence in Guatemalan school-boys of different height and socioeconomic status, showed that during the active hours of the day, the stunted (low income) group spent less time than the taller (middle income) group in 'sedentary' activities (434 ± 160 vs 566 ± 159 min. P < 0.01) and more time in 'light' activities that demanded some degree of physical effort (213 ± 136 vs 103 ± 94 minutes/day, P < 0.01) (Ramirez and Torun, 1994). This was probably due to the different lifestyles imposed by the different socioeconomic conditions of the two groups of children.


Figure 2a Total energy expenditure estimated by heart rate monitoring: boys.


Figure 2a Total energy expenditure estimated by heart rate monitoring: girls.

Table 6 Total daily energy expenditure of well-nourished and of stunted or marginally malnourished children, measured with heart-rate monitoring techniques and expressed as multiples of basal metabolic rate

Age

n

Energy expenditure or PAL

Condition

Reference

Boys

6.9 ± 0.5

41

1.60 ± 0.35

Normal

Spurr & Reina (1989)

7.1 ± 0.6

42

1.46 ± 0.29

Underweight


11.1 ± 0.6

54

1.74 ± 0.45

Normal

Spurr & Reina (1989)

11.0 ± 0.6

82

1.77 ± 0.47

Underweight


11.1 ± 0.5

34

1.75 ± 0.35

Normal

Ramirez & Torun (1994)

10.8 ± 0.5

34

1.83 ± 0.31

Stunted


14.8 ± 0.5

34

1.84 ± 0.50

Normal

Spurr & Reina (1989)

14.8 ± 0.6

47

1.92 ± 0.43

Underweight


Girls

7.0 ± 0.7

29

1.53 ± 0.38

Normal

Spurr & Reina (1989)

7.3 ± 0.7

20

1.43 ± 0.16

Underweight


10.8 ± 0 7

24

1.45 ± 0.21

Normal

Spurr & Reina (1989)

10.8 ± 0.5

32

1.57 ± 0.38

Underweight


14.9 ± 0.6

19

1.61 ± 0.31

Normal

Spurr & Reina (1989)

15.2 ± 0.5

22

1.61 ± 0.43

Underweight



Figure 3a
Total energy expenditure estimated by heart rate monitoring, excluding stunted and underweight boys.


Figure 3b
Total energy expenditure estimated by heart rate monitoring, excluding stunted and underweight girls.


Figure 4a
Total energy expenditure estimated with doubly labeled water or by heart rate monitoring, excluding stunted and underweight boys. Solid symbols: doubly labeled water.


Figure 4b
Total energy expenditure estimated with doubly labeled water or by heart rate monitoring, excluding stunted and underweight girls. Solid symbols: doubly labeled water.

Table 7 Groups of children, classified by sex and age, whose total daily energy expenditure was estimated from time-motion observations or activity diariesa




Total energy expenditure






Age (y)

n

Weight
(kg)

(kcal/d)

(kcal/kg/d)

PALb

Country

Condition

Methodc

Source

Boys

1.5

12d

9.3

725e,f

78.5e,f

1.39

Gambia

Mild malnutrition

O-Estimated EC

Lawrence et al (1991)

2-6

26

12.7 ± 3.2

1026f

81f

1.35

Guatemala

Stunted

O-Estimated EC

Torun (1990b)

4-6

25

17 ± 2

1130

66.5

1.27

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

7-9

26

24 ± 3

1499

62.5

1.43

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

10-12

25

32 ± 4

1971

61.6

1.61

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

12-14

16

31.3 ± 5.6

1810

58.0

1.49

Singapore

Normal

D-Measured EC

Banerjee & Saha (1972)

13-15

24

47 ± 6

2043

43.5

1.37

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

14.5 ± 0.4

102

51 ± 10

2626

51.6

1.68

UK

Normal

D-Adult EC

Durnin (1971)

14.6 ± 2.9

75d

49.3 ± 12.8

2222 ± 572f

45.1f

1.45

Canada

Normal

D-Estimated EC

Bouchard et al (1983)

16-17

65

69.4 ± 9.5

2766 ± 247

39.9

1.47

Australia

Normal, Students

D-Adult EC

McNaughton et al (1970a,b)

16-17

9

65.0 ± 9.6

2886 ± 235

444

1.60

Australia

Normal, Workers

D-Adult EC

McNaughton et al (1970a)

16-19

32

56 ± 5

2726

48.7

1.71

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

18-19

12

72.3 ± 8.1

2714 ± 276

37.4

1.46

Australia

Normal, Students

D-Adult EC

McNaughton et al (1970a)

18-19

9

68.4 ± 8.4

2740 ± 268

40.1

1.52

Australia

Normal, Workers

D-Adult EC

McNaughton et al (1970a)

Girls

1.5

12d

9.3

725e,f

78.5e,f

1.43

Gambia

Mild malnutrition

O-Estimated EC

Lawrence et al (1991)

2-6

22

12.7 ± 3.2

1026f

81f

1.41

Guatemala

Stunted

O-Estimated EC

Torun (1990b)

4-6

27

17 ± 2

1058

62.2

1.28

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

7-9

24

24 ± 2

1528

63.7

1.57

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

13-15

24

46 ± 3

1744

37.9

1.33

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

14.5 ± 0.5

90

52 ± 8

2211

42.5

1.59

UK

Normal

D-Adult EC

Durnin (1971)

14.6 ± 2.9

75d

49.3 ± 12.8

2222 ± 572f

45.1f

1.64

Canada

Normal

D-Estimated EC

Bouchard et al (1983)

16-17

6

50.9 ± 5.3

1893 ± 195

37.2

1.38

USA

Normal

D-Estimated EC

Bradfield et al (1971)

16-17

113

58.3 ± 5.4

2025 ± 167

34.7

1.37

Australia

Normal, Students

D-Adult EC

McNaughton et al (1970a)

16-17

32

54.8 ± 7.2

2139 ± 237

39.2

1.50

Australia

Normal, Workers

D-Adult EC

McNaughton et al (1970a)

16-19

32

50 ± 3

1922

38.4

1.49

Philippines

Normal

O-Estimated EC

Guzman et al (1991)

18-19

21

58.7 ± 5.4

1949 ± 195

33.2

1.38

Australia

Normal, Students

D-Adult EC

McNaughton et al (1970a,b)

18-19

24

54.3 ± 5.6

2073 ± 159

38.2

1.53

Australia

Normal, Workers

D-Adult EC

McNaughton et al (1970a,b)

a Energy expenditure data published by the authors or calculated from their data by B. Torun.
b Physical Activity Level calculated using BMR estimated with Schofield's equations (1985).
c O: Observations during daytime and diary or recall interview at night. D: Activity diary. EC: Energy cost of activities.
d Assume 50% boys and 50% girls.
e Mean of wet (76 kal/kg) and dry (81 kcal/kg) seasons.
f Using the same mean values for boys and girls.

Time-motion data and comparison of methods

PALs calculated from heart rate studies coincided within 5% with those calculated from doubly-labeled water studies, except for girls 6-13 years old (Tables 3 and 5). Figure 4 also indicates that the estimates of daily energy expenditure per unit of body weight calculated by heart rate monitoring coincide quite well with those based on doubly-labeled water, at least among non stunted, well nourished boys and girls.

A review of the literature allowed us to identify several studies that estimated total daily energy expenditure of children from time-motion observations or activity diaries recorded for several days, combined with indirect calorimetry measurements or estimates of the energy cost of the recorded activities. The results of those studies, listed in Table 7, were published as such by the authors or calculated by us from their data.


Figure 5a
Selected values of total energy expenditure estimated with time-motion/diary methods, compared with doubly labeled water (DLW) and heart rate monitoring (HR)*: boys. *B; Bouchard et al 1983; b: Banerjee & Saha 1972; D: Durnin 1971; G: Guzman et al 1991; L Lawrence et al 1988; M: MaNaughton et al 1970a,b; T: Torun 1990


Figure 5b
Selected values of total energy expenditure estimated with time-motion/diary methods, compared with doubly labeled water (DEW) and heart rate monitoring (HR)*: girls. *B; Bouchard et al 1983; b: Banerjee & Saha 1972; D: Durnin 1971; G: Guzman et al 1991; L Lawrence et al 1988; M: MaNaughton et al 1970a,b; T: Torun 1990

Figure 5 shows all the experimental data from the studies described in Tables 2, 4 and 7. Most time-motion/diary results agree reasonably well with the results from doubly-labeled water and heart rate studies, but there is a tendency to underestimate the energy expenditure of older adolescents, especially boys, with the diary method.

Conclusions

Total daily energy expenditure of free-living children has been measured by a limited number of investigators using doubly-labeled water or adequate heart rate monitoring techniques. Most of those studies have been done in industrialized countries, and none in school aged children or adolescents in rural areas of developing countries.

The experimental results suggest that current FAO/ WHO/UNU recommendations for dietary energy are too high for children under 5, and possibly under 7, years of age. By contrast, current dietary recommendations for adolescent boys and for girls around puberty seem somewhat low.

Energy expenditure per unit of body weight of stunted or mildly underweight, but otherwise healthy, school-children and adolescents in developing countries tends to be higher than among those with adequate height and weight. The causes for this must be explored further. In the meantime it seems convenient to make dietary recommendations based on the ideal weights or PALs of the general population.

The validity of these conclusions must be confirmed by other studies, as they are based on research carried out within a very narrow range of geographic and social environments, and most investigations with doubly labeled water or heart rate monitoring in industrialized countries involved small numbers of children in each age and sex group. Studies with heart-rate monitoring in developing countries included larger series of children, but they were done mainly among low income urban groups.

Studies are especially needed in rural areas of the developing world and among middle and upper socioeconomic groups of children in developing and industrialized cities. The minute-by-minute heart rate monitoring technique seems promising for this purpose, provided that the samples of children studied are of appropriate size. If finances allow it, they should be validated in the field with the doubly-labeled water method.

Time-motion/diary techniques can be useful to confirm the accuracy of the recommendations if the values used for the energy cost of activities are appropriate for children and adolescents (Town, 1983, 1990a). They also provide important information on activity patterns that will allow better estimates of the 24-h PAL, and an understanding of the behavioral determinants of physical activity in children and adolescents.

Estimates of basal metabolic rate to calculate total energy expenditure

To calculate the energy equivalent of a PAL value, it is multiplied by the BMR. The 1985 FAO/WHO/UNU Expert Consultation endorsed the use of the mathematical equations derived by Schofield, which take into account sex, age and body weight, to estimate a population's mean BMR. Although Schofield revised and modified his equations (Schofield, 1985), those initially published in the FAO/WHO/UNU report on Energy and Protein Requirements are used more often. The two sets of equations give similar values (within ± 1-2%), except for girls 3-10 years old, where the FAO/WHO/ UNU equations give BMR's 6-7% higher than the revised equations. Thus, the PAL of those girls is lower when calculated with the FAO/WHO/UNU equations. In this review we have used the revised equations (Schofield, 1985).

The PAL approach was recommended by the FAO/ WHO/UNU Experts to calculate TEE of adult populations with occupations and lifestyles that involved different PALs. It was used to estimate TEE of children and adolescents 10-18 years old with a pattern of activities that reflected the lifestyle of children in developed countries who spend several hours at school every day (FAO/WHO/UNU, 1985). No calculations were made for those with more energy-demanding lifestyles. This can be corrected, but doubts still remain about the accuracy of the Schofield-FAO/WHO/UNU equations to predict BMR in all races. This has been addressed by authors such as Henry & Rees (1988) and Elia (1992). Table 8 illustrates some of their conclusions about the possibility of over- or underestimating BMR in adults with Schofield's equations.

Accuracy of mathematical estimations of BMR

We explored the accuracy of the Schofield equations to estimate BMR of children and adolescents from various published and unpublished reports. Some studies measured BMR and others measured resting metabolic rate (RMR). The conditions for the latter varied from quasi basal conditions (supine position, 10-12 h fasting, transported by vehicle to the laboratory, resting 30-60 min prior to the measurement) to measurements done in supine, sitting and standing positions, 2-4 h after a light meal and resting for 15-45 min before the test.

The results for measured BMR are shown in Tables 9 and 10. Those results, however, must be interpreted with some caution. For example, Bandini et al (1990b) applied Weir's equation (1948) to correct for the difference in the volumes of inspired and expired air, whereas some of the others apparently did not. When only expired volume is measured and Weir's correction is not applied, BMR is underestimated by about 5%. Some systems that use a ventilated hood and compare the concentration of inhaled and exhaled O2 and CO2, such as the diaferometer used by Torun and Viteri (1981a), and the system used by Livingstone et al (1992a), compensate for the difference between inspired and expired air. Saris et al (1989) used a whole body indirect calorimeter that could also have compensated for that difference.

Table 8 Percentage by which Schofield equations overestimate ( + ) or underestimate ( - ) basal metabolic rate in different ethnic groups (18-60 years old)a


Male

Female

Ethnicity

Mean (%)

Sample size

Mean (%)

Sample size

Philippino

+9.6

82

+ 0.3

16

Indian

+ 12.7

48

+ 12.9

7

Japanese

+ 8.3

123

+ 7.9

71

Brazilian

+ 8.1

122

-

-

Chinese

+ 8.2

232

+ 3.4

156

Malay

+ 9.3

62

-

-

Javanese

+ 5.1

82

-

-

Mayan

+ 0.0

68

-

-

Chippewa Indian

- 18.5

5

- 18.5

5

a Source: Henry & Rees 1988).

With that methodological caveat in mind, Table 9 shows the BMR of boys and girls of different age groups measured in various countries, and compares them with the BMR calculated with Schofield's equations (1985). There seems to be a difference between developed and developing countries, an age-related trend in the data from the latter, and no major effects related to stunting or mild undernutrition. This can be seen more clearly in Table 10 Except for the Colombian underweight preschool aged boys, the difference or coincidence between measured and calculated BMR was similar for boys and girls of the same age groups, either with adequate weight and height, moderately stunted or mildly underweight.

In terms of age and sex, Schofield's equations overestimated the BMR of well-nourished, stunted or underweight Guatemalan, Colombian and Chinese preschoolers by about 10-12% in boys, and by 6-9% in girls. They coincided with measured BMR in boys and girls 7-16 years old in Holland, the UK and the USA, but overestimated the BMR of Colombian boys of that age by about 5%. That overestimation was not observed in their female counterparts, nor in Chinese girls 12-15 years old. By contrast W Wong (personal communication to B Torun) found that Schofield's equations overestimated by about 6% the BMR of 9-12 year-old hispanic and oriental girls living in Houston, Texas. The equations also overestimated by 9% the BMR of Chinese girls 15-18 years old in Guangzhou, China (Table 10).

In addition to those geographic and/or ethnic differences, Henry indicated that BMR in Beninese and Indonesian children is 8-10% lower than in the U.S. and Europe (personal communication).

More evidence about the tendency of current mathematical equations to overestimate BMR of many children and adolescents is derived from measurements of resting metabolic rates that should have been between about 15 and 20% higher than BMR, considering the conditions under which RMR is measured. For example, unpublished studies by Torun and coworkers in 68 Guatemalan 10-12 year-old boys of two economic income groups and repeated measurements in 24 stunted but well nourished girls of that same age, showed that in both sexes the non-fasting mean RMR measured after 15 min in supine, sitting and standing positions was only 7% greater than their BMR calculated with Schofield's equations. This was about 10% less than expected under the prevailing RMR conditions.

Firouzbakhsh et al (1993) reported similar results in 92 boys and 107 girls, 5-16 years old, living in or near Los Angeles, California. RMR measured 2-3 h post-prandial and after resting for 15-30 min. coincided with the calculated BMR within ± 8% in all age groups and either sex.

Table 9 Comparison of measured BMR with BMR calculated from Schofield's equations (1985)

Age

n

Country

Measured
(MJ/d)

Calculated
(MJ/d)

Differencea
(%)

Reference

Boys

2.5 - 3.8

11b

Guatemala

2.81

3.12

+ 10.9

Torun & Viteri (1981a)

2-5

22

Colombia

3.21 ± 0.27

3.59

+ 11.9

Spurr et al (1992)

2-5

17c

Colombia

2.61 ± 0.38

3.27

+ 25.2

Spurr et al (1992)

5-6

71

China

3.42 ± 0.30

3.79

+ 10.8

Ho et al (1988)

6-8

43

Colombia

4.05 ± 0.56

4.20

+ 3.7

Spurr et al(1992)

6-8

42c

Colombia

3.66 ± 0.47

3.92

+ 7.0

Spurr et al (1992)

7-7.9

6

UK

4.72 ± 0.78

4.52

- 4.2

Livingstone et al (1992a)

9-9.5

5

UK

4.75 ± 0.65

4.98

+ 4.8

Livingstone et al (1992a)

9.3 ± 1.4

9

Holland

5.08

4.94

- 2.7

Saris et al (1989)

10-12

54

Colombia

4.98 ± 0.70

5.19

+ 4.2

Spurr et al (1992)

10-12

80c

Colombia

4.37 ± 0.66

4.74

+ 8.4

Spurr et al (1992)

12-12.9

5

UK

6.30 ± 0.83

6.00

- 4.8

Livingstone et al (1992a)

14-16

34

Colombia

6.17 ± 0.74

6.35

+ 2.9

Spurr et al (1992)

14-16

47c

Colombia

5.44 ± 0.83

5.57

+ 2.5

Spurr et al (1992)

14.5 ± 1.5

14

USA

7.29 ± 0.77

6.93

- 4.9

Bandini et al (1990b)

15-15.9

3

UK

6.70 ± 0.36

6.51

- 2.9

Livingstone et al (1992a)

Girls

2-5

20

Colombia

3.10 ± 0.42

3.29

+ 6.1

Spurr et al (1992)

2-5

19c

Colombia

2.84 ± 0.38

3.09

+ 8.8

Spurr et al (1992)

5-6

85

China

3.21 ± 0.30

3.50

+ 9.1

Ho et al (1988)

6-8

29

Colombia

3.84 ± 0.51

3.92

+ 2.1

Spurr et al (1992)

6-8

25c

Colombia

3.81 ± 0.52

3.64

- 4.5

Spurr et al (1992)

7-7.9

5

UK

4.36 ± 0.86

4.03

- 7.6

Livingstone et al (1992a)

8.1 ± 1.3

10

Holland

4.80

4.69

- 2.4

Saris et al (1989)

9-9.9

4

UK

4.43 ± 0.23

4.87

+ 9.9

Livingstone et al (1992a)

10-12

29

Colombia

4.85 ± 0.57

4.74

- 2.3

Spurr et al (1992)

10-12

33c

Colombia

4.29 ± 0.82

4.39

+ 2.3

Spurr et al (1992)

12-12.9

16

China

5.26 ± 0.38

5.21

- 0.9

Min & Ho (1991)

12-12.9

5

UK

5.85 ± 0.66

5.43

- 7.2

Livingstone et al (1992a)

13-13.9

40

China

5.30 ± 0.43

5.26

- 0.8

Min & Ho (1991)

14-14.9

23

China

5.35 ± 0.36

5.48

+ 2.4

Min & Ho (1991)

14-16

15

Colombia

5.48 ± 0.58

5.69

+ 3.9

Spurr et al (1992)

14-16

19c

Colombia

5.19 ± 0.43

5.22

+ 0.5

Spurr et al (1992)

15-15.9

14

China

5.26 ± 0.24

5.57

+ 5.8

Min & Ho (1991)

16 16.9

13

China

4.99 ± 0.31

5.49

+ 10.0

Min & Ho (1991)

14.3 ± 1.0

14

USA

6.03 ± 0.56

6.02

- 0.2

Bandini et al (1990b)

15-15.9

3

UK

5.14 ± 1.00

6.00

+ 16.8

Livingstone et al (1992a)

17-17.9

20

China

4.82 ± 0.34

5.55

+ 15.2

Min & Ho (1991)

a + indicates that Schofield's formulas give higher values, and - indicates lower values.
b Adequate weight but previously malnourished. Height-for-age > 1.5 s.d. below the NCHS median. c Weight-for-age and weight-for-height < 95% of Colombian standards (Rueda-Williamson et al, 1969)

Conclusions

Even though there may be some methodological doubts about their interpretation, the preceding observations and the data shown in Tables 9 and 10 indicate that the mathematical equations endorsed in 1985 by FAO/ WHO/UNU to calculate BMR, tend to overestimate the results and, consequently, the TEE of many children and adolescents calculated from estimates of the population's PAL.

It is necessary to decide whether a single set of predictive equations for BMR should be used universally for all children and adolescents, acknowledging an error of certain magnitude in some cases, or whether specific equations must be derived and applied to certain races or to children who live in some parts of the world.

The extensive review of BMR data presently being done by CJK Henry under the auspices of IDECG and with funding from the Nestle Foundation should help to clarify this issue.

Time allocation to different activities

The habitual physical activity of children and adolescents differs among societies with different cultural characteristics and among groups of different socioeconomic conditions in the same society. For example, while many children in rural areas of developing countries partake in domestic chores or are part of their community's labor force from an early age (Rodgers and Standing, 1981), most children in industrialized countries attend school for several hours, and those in a better socioeconomic situation do not have any work obligations.

Many studies have addressed various aspects of the time allocated by children to their daily activities. These have been performed with diverse objectives by researchers whose main interests are in nutrition, physiology, anthropology, human behavior or economics. Methods have included continuous or spot observations, recall interviews with children or caretakers, subject or observer diaries, and analysis of heart rate patterns. Results have been analyzed and presented as specific activities or classified according to their purpose or physical effort.

Table 10 Mean differences between measured MBR in children of different races and BMR calculated from Schofield's equations (1985)

Country/Race

Age (y)

Conditiona

n

Differenceb

Reference

Boys

Guatemala/Mixed

2-4

Stunted

11

+ 10.9%

Torun & Viteri (1981a)

Colombia/Mixed

2-5


22

+ 11.9%

Spurr et al (1992)

Colombia/Mixed

2-5

Underweight

17

+ 25.2%

Spurr et al (1992)

China/Chinese

5-6


71

+ 10.8%

Ho et al (1988)

Colombia/Mixed

6-16


131

+ 3.7%

Spurr et al (1992)

Colombia/Mixed

6-16

Underweight

169

+ 6.4%

Spurr et al (1992)

Holland, UK,

7-16


42

- 3.0%

Saris et al (1989)

USA/Caucasian





Livingstone et al (1992a)






Bandini et al (1990b)

Girls

Colombia/Mixed

2-5


20

+ 6.1%

Spurr et al (1992)

Colombia/Mixed

2-5

Underweight

19

+ 8.8%

Spurr et al (1992)

China/Chinese

5-6


85

+ 9.1%

Ho et al (1988)

Colombia/Mixed

6-16


73

+ 0.2%

Spurr et al (1992)

Colombia/Mixed

6-16

Underweight

77

- 1.0%

Spurr et al (1992)

Holland, UK,

7-16


41

- 0.3%

Saris et al (1989),

USA/Caucasian





Livingstone et al (1992a),






Bandini et al (1992b)

China/Chinese

12-15


79

+ 0.1%

Min & Ho (1991)

China/Chinese

15-18


47

+ 9.1%

Min & Ho (1991)

a Stunted: >1.5 s.d. below the NCHS median of height-for-age. Underweight: <95% of weight-for-age and weight-for-height in comparison to Colombian children of upper socioeconomic groups (Rueda-Williamson et al, 1969). All others: adequate height and weight for age.
b + indicates that Schofield's formulas give higher values, and - indicates lower values.
c Mixed: various degrees of mixture between caucasian and indigenous.

Quantification of total daily time distribution

The variety of methods and the lack of a standard for presenting the data make it difficult to compare across societies and to combine the results of different studies. This is further impaired by the selective nature of some studies that focus on one type of activity, and by incomplete information, such as indicating children's involvement as a percentage of activities performed without information on the time period. We, nevertheless, made an effort to compare and combine information after a critical revision of studies with time allocation data.

From a review of more than 70 studies that had some information, we identified 39 with data of sufficient quality and completeness to quantify children's total daily time allocation (Table 11).

Table 11 Studies used to evaluate and quantify children's time allocation (see 'References' for full bibliographic information)

Acharya & Bennett (1981)

Loucky (1988)

Andersen et al (1978)

MacConnie et al (1982)

Banerjee & Saha (1972)

McNaughton & Cahn (1970a,b)

Berio (1984)

Mueller (1984)

Bradfield et al (1971)

Munroe et al (1983)

Cain (1977)

Munroe & Munroe (1989)

Carbañero (1980)

Nag et al (1978)

Colfer (1981)

Niemi et al (1981)

Dresen et al (1982)

Paolisso & Sackett (1988)

Durnin (1971)

Ramirez & Torún (1994)

Franklin & Harrell (1985)

Rutenfranz et al (1974)

Gilliam et al (1981)

Saris et al (1979)

Grossman (1984)

Seliger et al (1974)

Guzmán (1991)

Shephard et al (1980)

Hart (1988)

Spady (1980)

Ho et al (1988)

Stefanik et al (1959)

Huenemann et al (1967)

Sunnegardh et al (1985)

Johnson et al (1956)

Torun et al (1993)

Johnson & Johnson (1987)

Turke (1988)

We classified activities according to two types of characteristics:

(1) Intensity of effort and energy expenditure: (a) sleep, (b) sedentary, (c) light, (d) moderate, (e) heavy. When those categories were used by the investigators, their criteria for classification were respected. When not, we allocated the time to the corresponding category according to the description of the activity or to the children's heart rate, following the criteria shown in Table 12.

(2) Nature or purpose of the activity: (a) sleep, (b) school, (c) domestic chores, (d) production (with or without wages), (e) non-work activities. Table 13 gives descriptive examples. 'Recreational activities' are mentioned in some studies. These are non sedentary leisure activities that involve more effort than the general 'non-work activities'.

Classification of activities according to their physical effort permits making estimates of total daily energy expenditure of children with different lifestyles. Most studies that describe the nature of activities, such as in Table 13, do not indicate the degree of physical effort involved. They must be assigned an energy cost, or at least an intensity of effort, to allow comparing with studies that allocate time according to the level of energy expenditure.

Table 12 Criteria to classify the physical effort of activities according to the children's heart rate

Sedentary

< 96

Light

96-120

Moderate

121-145

Heavy

> 145

Table 13 Selected examples of activities classified according to their nature or purpose

Sleep

In bed at night; napping.

School

Classroom work; recess; other school activities.

Domestic chores

Child care; cleaning house; washing dishes; laundry; food preparation and cooking; miscellaneous household crafts and tasks; fetching water; fuel collection.

Production

Agricultural activities; household manufacturing and crafts for sale; textile work; hunting, fishing and gathering; trading and selling; wage work.

Non-work activities

Eating; personal care and hygiene; resting; walking and travelling; school homework; play and leisure; social and religious activities.

Although the energy cost of some activities listed in Table 13 has been measured by indirect calorimetry, that of many others has not (see review by Torun, 1990a). Furthermore, many tasks involve a variety of specific activities with different energy demands (for example, house cleaning can involve light dusting or heavy sweeping), and pauses of different length may be interspersed with the actual physical endeavor. Consequently, we made an empirical estimation of the physical effort involved in the activity categories of Table 13, based on the energy costs that have been measured, the descriptions available in some studies, our own experience, and the assumption that domestic and productive activities in developing societies involve more physical effort than their equivalents in developed countries or urban centers. This is shown in Table 14. As with all empirical estimations, this can later be modified but it is a starting point to compare studies.

The age groups were classified as 2-5, 5-9, 10-14 and 15-19 years, as this was the age breakdown allowed by most of the reviewed studies. In addition to the overlap between the 2-5 and 5-9 groups, there was some overlap between the other categories, as some studies presented data on children aged 9-11 or 13-15.

Tables 15 and 16 show the factorial distribution of the time allocated by boys and girls, respectively, to activities with different energy demands. They are presented separately for children from industrialized countries, cities in developing countries, and rural areas in the latter, as the activities performed and the energy expenditure involved vary in each of those settings.

Table 14 Effort empirically assumed to be required by the activities listed in Table 13


Time spent in physical effort (%) corresponding to:

Time spent in:

Sedentary

Light

Moderate

Heavy

School

67

33



Domestic chores

cities and industrialized societies


50

50


rural developing societies


33

67


Production

cities and industrialized societies


50

50


rural developing countries


33

34

33

Non-work activities

30

30

30

10

Recreational activitiesa


30

50

20

a Described as such in some studies. They Are non-work activities. that Are not sedentary

Table 15 Weighted averages of time allocated by boys to activities that require different levels of physical efforta




Mean number of daily hours at:

Society

No. of studies

No. of childrenb

Sleep

Sedentary

Light

Moderate

Heavy

Mean daily energy expenditure PALc

5-9 Years



(1)d

(1.3)

(2.2)

(2.9)

(3.6)


Industrialized, urban and rural

5

225

10.5

6

4

2

1.5

1.60

Developing, urban

2

81

11

5

3

3

1

1.56

Developing, rural

13

340

10

4

4.5

4

1.5

1.75

10-14 Years



(1)

(1.3)

(2.2)

(2.9)

(3.6)


Industrialized, urban and rural

9

887

10.5

5.5

4.5

2.5

1

1.60

Developing, urban

3

133

8.5

7.5

4

3.5

0.5

1.62

Developing, rural

12

450

9

4

4.5

4.5

2

1.85

15-19 Years



(1)

(1.3)

(2.2)

(3)

(5)


Industrialized, urban and rural

5

838

9.5

5

6

3

0.5

1.70

Developing, urban

1

32

8.5

7

6

2.5

0

1.60

Developing, rural

9

200

8

3.5

5

5

2.5

2.13

a Sources are listed in Table 11. Averages were weighted on the number of children in each study; refer to the text for explanation of procedure when the exact number of children was not known or it was too large in relation to other studies.
b Some numbers of children are approximations, as some studies do not give exact figures.
c Expressed as multiples of BMR or Physical Activity Level. Not calculated when time allocation was reported in only one study.
d Energy cost of activities, in multiples of BMR, as suggested by Torun (1990a)

Table 16 Weighted averages of time allocated by girls to activities that require different levels of physical efforta




Mean number of daily hours at:

Society

No. of studies

No. of childrenb

Sleep

Sedentary

Light

Moderate

Heavy

Mean daily energy expenditure PALc

5-9 Years



(1)d

(1.3)

(2.2)

(2.9)

(3.3)


Industrialized, urban and rural

4

232

10.5

6

4

2

1.5

1.58

Developing, urban

2

81

11.5

5

4

2.5

1

1.56

Developing, rural

13

310

10

4

4.5

4

1.5

1.74

10-14 Years



(1)

(1.3)

(2.2)

(2.9)

(3.3)


Industrialized, urban and rural

4

700

10

6.5

4

2.5

1

1.58

Developing, urban

2

73e

8.5

6

4.5

4.5

0.5

1.70

Developing, rural

12

400

9

3.5

4.5

5

2

1.86

15-19 Years



(1)

(1.3)

(2.2)

(3)

(4.5)


Industrialized, urban and rural

7

1023

9.5

5.5

6

2.5

0.5

1.65

Developing, urban

1

32

8

7

6.5

2.5

0

1.62

Developing, rural

9

180

8

3

5.5

5.5

2

2.06

a Sources are listed in Table 11. Averages were weighted on the number of children in each study; refer to the text for explanation of procedure when the exact number of children was not known or it was too large in relation to other studies.
b Some numbers of children are approximations, as some studies do not give exact figures.
c Expressed as multiples of BMR or Physical Activity Level. Not calculated when time allocation was reported in only one study.
d Energy cost of activities, in multiples of BMR, as suggested by Torun (1990a)
e In one of the two studies 24 girls were studied longitudinally four times at 3-month-intervals.

Time distributions were calculated as weighted means from several studies, weighting them for the number of children involved, and rounding the time to the nearest half-hour. In studies that only presented the number of households, the number of children was assumed to be either 50 or 33% of those households, depending on other information related to the study. When the number of boys and girls was not given, equal numbers were assumed for each sex. When a study greatly outnumbered the sample size of all others for that sex and age category, only 50% of its sample size was used to calculate the weighted mean in order to reduce the bias of the results towards a single study. For example, 8 of 9 studies on boys 10-14 aged years old in industrialized countries involved between 11 and 171 children, whereas the ninth study involved 360; a weight of 180 was given to that study.

Tables 15 and 16 show that, compared with children in industrialized societies, children in developing rural areas sleep less at night, participate longer in moderate and/or heavy physical activities, and have a greater energy expenditure in relation to their basal metabolic rate. There are very few studies on children in cities from developing countries, but their physical activity falls between the other two groups, resembling more that of children in industrialized countries than that of their rural counterparts. Within the same type of society, there were no striking differences between boys (Table 15) and girls (Table 16).

In terms of the nature or purpose of the activities, children of school age in industrialized countries spend between 4.5 and 7.5 h at school during school-days. In developing countries, children in urban areas spend similar amounts of time at school, although many from the lower socioeconomic groups do not attend school at all, especially after 12 years of age. School attendance is less among their rural counterparts, who average between 0.5 and 2 h per day (Table 17).

Table 17 also shows that children in rural traditional societies of developing countries begin domestic and productive work at preschool age, and from 10 years onwards they have an important daily workload. Girls are involved in domestic work longer than boys and, after 9 years of age, boys spend more time than girls in production and wage-earning chores.

Estimations of total daily energy expenditure

Total daily energy expenditure was estimated from the time allocations in Tables 1:5 and 16, and the energy costs of sedentary, light, moderate and heavy activities suggested by Torun (1990a) as shown in those tables; the energy cost of sleep was assumed to equal basal metabolic rate. The results, expressed as PAL or multiples of BMR, are shown in the last column of those tables.

Table 17 Time allocated to school attendance, domestic work, productive work and non-work activities by children of native, traditional, rural populations from several countriesa


Time allocated to (rounded to 0.5 h):


School

Domestic work

Production work

Non-work and sleep

2-5 Years

Boys

<0.5

0.5

0.5

23

Girls

<0.5

1

<0.5

23

5-9 Years

Boys

1

0.5

1.5

21

Girls

1

1.5

1.5

20

10-14 Years

Boys

2

1

4

17

Girls

2

2.5

2.5

17

15-19 Years

Boys

1.5

1

6

15.5

Girls

1.5

3.5

3.5

15.5

a Bangladesh (Cain, 1977), Borneo (Colfer, 1981), Botswana (Mueller, 1984), Guatemala (Loucky, 1988), Indonesia (Nag et al, 1978; Hart, 1988), Ivory Coast (Berio, 1984), Kenya (Munroe et al, 1983; Munroe & Munroe, 1989), Papua/New Guinea (Grossman, 1984), Panama (Franklin & Harrell, 1985), Peru (Munroe et al, 1983; Johnson & Johnson, 1987), Philippines (Carbañero, 1980), Nepal (Nag et al, 1978; Acharya & Bennett, 1981), Venezuela (Paolisso & Sackett, 1987), Western Caroline Islands (Turke, 1988).

PALs were converted into kcal/kg/day applying Schofield's equations (Schofield, 1985) to the body weight at the mid-point of the age intervals shown in Table 18 (i.e. 7.5, 12.5 and 17.5y). The NCHS/WHO median weight for age was used for children in industrialized countries, and it was assumed that the average weights for children in urban and rural developing areas corresponded to the 30th and 20th centiles of the NCHS values, respectively. The remarkable agreement with the estimates of total daily energy expenditure by the doubly-labeled water and heart rate methods (Figure 6) suggests that the criteria for classification of activities shown in Tables 13 and 14 and the factors used to assign them an energy cost (Tables 15 and 16) were good estimates.

Tables 15, 16 and 18 suggest that total energy expenditure expressed as PAL is similar for boys and girls within each age group and geographic/developmental category. In industrialized countries, it is constant between 5 and 14 years (and similar to cities in developing countries), and it increases by about 5% after that age. In rural developing societies, daily energy expenditure increases with age, as a reflection of children's increasing involvement in energy-demanding chores.

An analysis of the estimates of total daily energy expenditure shown in Table 18 indicates that, based on multiples of BMR, children of 5-9, 10-14 and 15-19 years spend about 10,15 and 25% more energy in rural developing societies than in industrialized countries. When expressed as kcal/kg, the corresponding increments in energy expenditure are about 15, 25 and 30% for the three age groups, respectively.

Table 18 Estimates of total daily energy expenditure of children based on the data shown in Tables 15 and 16, and the median weights assumed for the age span



Estimated daily energy expenditure

Age (y)

Assumed weighta (kg)

PAL

(kcal/kg/day)b

Boys

Industrialized countries

5-9

24.0

1.60

69.9

10-14

42.3

1.60

53.2

15-19

67.8

1.70

46.6

Developing cities

5-9

22.5

1.56

70.4

10-14

38.6

1.62

56.3

Developing rural areas

5-9

21.6

1.75

80.5

10-14

36.5

1.85

66.1

15-19

60.3

2.13

60.9

Girls

Industrialized countries

5-9

23.3

1.58

65.0

10-14

43.8

1.58

46.1

15-19

56.7

1.65

42.2

Developing cities

5-9

21.6

1.56

66.8

10-14

40.0

1.70

52.2

Developing rural areas

5-9

20.7

1.74

76.2

10-14

37.6

1.86

59.2

15-19

50.4

2.06

55.9

a Children in industrialized countries: NCHS median for mid-point of age range (i.e., 7.5, 12.5 and 17.5y); children in developing urban centers: 30th centile; children in rural societies: 20th centile.
b Basal metabolic rate was converted to kcal/kg/day using the formulas suggested by Schofield (1985).


Figure 6a
Total energy expenditure from time allocation (TA) compared with doubly labeled water (DLW) and heart rate monitoring (HR): boys.


Figure 6b
Total energy expenditure from time allocation (TA) compared with doubly labeled water (DLW) and heart rate monitoring (HR): girls.

Conclusions

We believe that more insightful information on children's time allocation and its energy cost is lying unanalyzed in existing databases of nutritional, physiological and anthropological studies. Efforts must be made to retrieve, analyze and present them in a standard manner to allow making better estimates of children's energy expenditure and requirements, as well as of the behavioural and social implications of their time distribution.

The data that we were able to analyze indicates that, beginning at least at 5 years of age, children in rural areas of developing countries spend more time in activities that require more physical effort than children in cities or industrialized countries.

It seems that time allocation of physical activity is similar in urban areas of industrialized and developing countries, but more information is needed from the latter to confirm this notion. Information is also needed on the time allocated to activities by children and adolescents of different socioeconomic groups.

Table 19 Mean 24-hour physical activity levels of children and adolescents in industrialized countries and in cities of developing countries (based on data in Tables 2, 4, 7, 15 and 16)a

Age (y)

Methodb

Boys

Girls

1-5

DLW


1.46 (86)c


1.44 (84)


HR (St)



1.42 (17)



TM (St)



1.36 (38)

1.42 (34)

6-13

DLW


1.79 (53)


1.80 (75)


HR

1.71 (149)

1.71 (274)

1.50 (80)

1.59 (181)


HR (St)

1.71 (125)

1.71 (274)

1.67 (10:1))

1.59 (181)


TM


1.51 (67)


1.57 (24)


TA


1.60 (1326)


1.59 (1086)

14-18

DLW


1.84 (37)


1.69 (34)


HR


1.81 (15)

1.65 (22)

1.63 (44)


HR (St)



1.61 (22)

1.63 (44)


TM


1.57 (304)


1.58 (253)


TA


1.70 (870)


1.65 (1055)

a Excluding studies with mean PAL < 1.40 for children over 5 years, and > 1.90 for all ages.
b DLW: doubly labeled water; HR: heart rate monitoring; TA: time allocation; TM: time-motion/diary. (St): stunted or mildly underweight; otherwise, normal.
c Weighted mean. Number of children in parenthesis.

The conversion of time allocation data to energy expenditure gives reasonable results when activities such as those listed in Table 13 are assigned the intensity of effort shown in Table 14, and the energy equivalents shown in Tables 15 and 16 are applied to sleep, sedentary, light, moderate and heavy activities.

When time allocation is converted into energy expenditure expressed as PAL, there is practically no difference between boys and girls within the same type of society.

Physical activity levels of children and adolescents

The occupational and habitual activities of adults are classified as light, moderate and heavy, and taken into account to calculate and recommend dietary energy intakes. The data presented in this document supports the suggestion that the same approach must be applied to children from 5 years of age onwards.

To do so, estimates must be made of the 24-hour PAL of children and adolescents with different lifestyles. This is usually associated with their geographic habitat (urban or rural, industrialized or developing country) and socioeconomic conditions.

An analysis of the PALs calculated in this review for children studied with doubly-labeled water, heart rate monitoring, time-motion/diary techniques and time allocation estimates allows making practical suggestions. Table 19 summarizes those calculations for industrialized countries and cities in developing countries, calculated as weighted means for the total number of boys or girls included in all studies with a specific technique. Studies with mean PAL < 1.40 for children over 5 years old were excluded, as well as those with PAL > 1.90 at all ages, as those figures are very unlikely to represent the habitual activity level of children in cities and industrialized countries. The mean PALS of normal and stunted children calculated from heart rate monitoring methods were combined as they were derived from otherwise healthy children, and in most cases they agreed within 4%.

There is hardly any information of TEE of children and adolescents living in rural developing countries. Therefore, we only estimated their PAL from time allocation data, as described in the preceding section and shown in Tables 15, 16 and 18.

The estimates of PALs from studies on time-motion/ diary records and time allocation data involve a series of assumptions on the energy cost of activities and tasks to calculate TEE. Thus, it seems more reasonable to use the data derived from doubly-labeled water and heart rate monitoring studies to suggest PALs to estimate the energy expenditure and requirements of children and adolescents from different populations. Such PALs, based on the data in Table 19, are shown in Table 20. Assuming that those levels of physical activity correspond to children and adolescents who are neither extremely sedentary nor active and are consuming dietary energy ad libitum, we suggest that they are equivalent to a moderate PAL.

The mean coefficient of variance (CV) of the studies with doubly-labeled water and heart rate monitoring in boys and girls 1-5, 6-13 and >14 years old shown in Tables 3 and 5 is 6%. We calculated the PAL of light and heavy lifestyles by subtracting or adding twice the CV (i.e. 12%) from the moderate PAL of children and adolescents over 5 years old (Table 20). It is unlikely that infants and preschoolers have a heavy physical lifestyle. Consequently, for that age group it is suggested that the mean of the PALs shown in Table 19 (measured by DLW or HR) be applied to a 'light' lifestyle, and the additional 12% (twice the mean CV) be applied to a 'moderate' PAL.

Table 20 Physical activity levels suggested to estimate total daily energy expenditure from the mean basal metabolic rate of children and adolescents



Habitual physical activity

Age (y)

Sex

Light

Moderate

Heavy

1-5

M, F

1.44

1.61


6-13

M

1.54

1.75

1.96

14-18

M

1.60

1.82

2.04

6-13

F

1.48

1.68

1.88

14-18

F

1.46

1.66

1.86

Table 21 Data from Table 20 rounded to the closest 0.05 PAL units



Habitual physical activity

Age (y)

Sex

Light

Moderate

Heavy

1-5

M, F

1.45

1.60

-

6-13

M

1.55

1.75

1.95

14-18

M

1.60

1.80

2.05

6-13

F

1.50

1.70

1.90

14-18

F

1.45

1.65

1.85

To facilitate remembering those PAL factors, it is further suggested to round them to the closest 0.05 PAL units, as shown in Table 21.

As more information on TEE and BMR of boys and girls with different lifestyles becomes available and the questions related to the mathematical equations to estimate BMR are cleared, the PALs shown in Table 21 may be modified. In the meantime, their use is suggested as a first approximation to estimate energy requirements in population groups where actual data is unavailable. Table 22 shows those estimates for boys and girls with median weights-for-age corresponding to the NCHS standards. Figure 7 compares them with measurements using doubly labeled water and heart rate monitoring, expressed as kcal/kg/day.

Table 22 Estimates of total daily energy expenditure from the physical activity levels suggested in Table 21 and basal metabolic rates calculated with Schofield's equations



Habitual physical activityb



Light

Moderate

Heavy

Age (y)

Weighta
(kg)

(kcal/d)

(kcal/kg/d)

(kcal/d)

(kcal/kg/d)

(kcal/d)

(kcal/kg/d)

Boys

1

10.4

854

82.1

942

90.6

c

c

2

12.3

1018

82.7

1123

91.3

c

c

3

14.6

1211

83.0

1337

91.6

c

c

4

16.7

1281

76.6

1413

84.6



5

18.7

1346

72.0

1486

79.4



6

20.7

1510

72.9

1704

82.3

1899

91.7

7

22.9

1587

69.3

1792

78.2

1996

87.2

8

25.3

1671

66.1

1887

74.6

2102

83.1

9

28.1

1770

63.0

1998

71.1

2227

79.2

10

31.4

1885

60.0

2126

67.7

2370

75.5

11

35.3

1988

56.3

2245

63.6

2501

70.9

12

39.8

2112

53.1

2384

59.9

2657

66.8

13

45.0

2254

50.1

2545

56.6

2836

63.0

14

50.8

2491

49.0

2803

55.2

3192

62.8

15

56.7

2659

46.9

2991

52.7

3406

60.1

16

62.1

2811

45.3

3163

50.9

3602

58.0

17

66.3

2930

44.2

3296

49.7

3755

56.6

18

68.9

3004

43.6

3379

49.1

3849

55.9

Girls

1

9.8

783

79.9

865

88.2

c

c

2

11.8

953

80.7

1051

89.1

c

c

3

14.1

1120

79.4

1236

87.6

c

c

4

16.0

1176

73.5

1297

81.1



5

17.7

1226

69.3

1352

76.4



6

19.5

1323

67.8

1499

76.9

1676

85.9

7

21.8

1393

63.9

1579

72.4

1764

80.9

8

24.8

1484

59.8

1682

67.8

1880

75.8

9

28.5

1597

56.0

1810

63.5

2023

71.0

10

32.5

1706

52.5

1933

59.4

2160

66.5

11

37.0

1783

48.2

2021

54.6

2259

61.0

12

41.5

1874

45.1

2123

51.2

2373

57.2

13

46.1

1966

42.6

2228

48.3

2490

54.0

14

50.3

1982

39.4

2256

44.8

2529

50.3

15

53.7

2048

38.1

2331

43.4

2613

48.7

16

55.9

2091

37.4

2379

42.6

2668

47.7

17

56.7

2107

37.2

2397

42.3

2688

47.0

18

56.6

2105

37.2

2395

42.3

2685

47.4

a Median weight for age, NCHS/WHO.
b PAL factors shown in Table 21.
c Assume values similar to moderate physical activity in children 1-3 years old.

Dietary energy intake

The most important criteria in choosing a method for collecting food intake data in children and adolescents are: (a) the technique should not interfere with the subject's dietary pattern; (b) the data should be representative of usual or habitual intake and (c) the technique should be suitable for application in large study groups.

The methods most frequently used in childhood and adolescent population groups are similar to those applied in adult studies, namely:

(1) Retrospective or food recall methods, which depend on dietary information given from memory by the child/ adolescent and/or parent/child carer. Several specific types of data collection fall within this category, including those aimed at quantifying actual intake for a precise time (usually the previous day, or 24-h recall) and those designed to elicit information about usual consumption patterns for a longer, less precisely defined time period (diet history or food frequency methods). More than one 24-h recall should be made on different days of the week, especially when there are cultural cyclic changes in food intake (e.g. weekdays compared with weekends). Recalls of more than 24 h are sometimes performed but the accuracy with which subjects and/or parents can remember food consumption is debatable, particularly if food intake patterns are highly unstructured or unstable. In the food frequency method, subjects and/or parents/child carers report by interview or self-administered questionnaire, the frequency of consumption of particular foods during a specified time span (week, month, year). A quantitative component is added by including the size and number of portions most frequently consumed for each food.

(2) Prospective or food record methods, which require that all food items consumed be recorded at the time of consumption. Intakes are quantified by direct weighing of the food, by estimates using, household measures or by collection of duplicate diets. Quantitative assessment of usual food intake can be obtained by increasing the number of measurement days. Seven days are generally assumed to represent a good compromise between precision, subject/parental cooperation, cultural dietary patterns and investigator workload.

Each of these methods has advantages and drawbacks when applied to children and adolescents. Ultimately, all survey methods are dependent on the motivation, compliance and ability of subjects and/or parents/child carers to report accurately habitual food intake.

Food intake data must then be converted into energy equivalents. This is often done disaggregating recipes into their food components and calculating their metabolizable energy as reported in food composition tables. Care must be taken to make all necessary conversions for the proper use of food composition data. A common error is applying to 'cooked' or 'wet' weight of foods the energy values for 'raw' or 'dry' foods that appear in composition tables, without applying adequate conversion factors.

A more accurate approach is to perform chemical or calorimetric analyses of samples of foods that are ready to be eaten. This is particularly useful to calculate the energy provided by food recipes that are unlikely to appear in food composition tables or that may be subject to variations. When the energy content of food is measured by bomb calorimetry, appropriate corrections must be made to calculate metabolizable energy.


Figure 7a
Energy expenditure calculated from estimates of habitual physical activity, compared with measurements using doubly labeled water and heart rate monitoring. Including data of stunted and underweight children: boys.


Figure 7b
Energy expenditure calculated from estimates of habitual physical activity, compared with measurements using doubly labeled water and heart rate monitoring. Including data of stunted and underweight children: girls.

Validity of energy intakes in children and adolescents

Most dietary intake studies in children assume that the data obtained are representative of habitual food consumption, and many recent studies concluded that energy intakes (EI) have declined in industrialized countries and more privileged groups in developing countries in response to a secular trend towards lower levels of activity in children and adolescents. However, studies in adults using doubly-labeled water (DLW) measurements of total energy expenditure (TEE) to validate EI have demonstrated that intake data may underestimate habitual food intake to a greater extent than has been appreciated (Prentice et al, 1986; Livingstone et al, 1990b; Schoeller, 1990). It is conceivable, therefore, that the reportedly low intakes of children may be artifacts of dietary survey methodology, rather than indicative of a diminution in energy expenditure.

Validation studies have been reported to assess the accuracy of EI in children and adolescents, using DLW measurements of TEE. These include studies of EI by 4-day weighted dietary record (WDR) in 1.5-4.5 year olds (n = 81) (Davies et al, 1994), by 7-day WDR in 7, 9, 12, 15 and 18 year olds (n = 58), by diet history (DH) in 3, 5, 7, 9, 12, 15 and 18 year olds (Livingstone et al, 1992b) and by 14 day estimated food records in non-obese and obese adolescents (n = 55) (Bandini et al, 1990a).


Figure 8
Comparison (± s.d.) of reported habitual energy intake and energy expenditure in (a) 1.5-4.5 year old children (Davies et al, 1994) and (b) non-obese and obese adolescents (Bandini et al, 1990a).


Figure 8
Comparison (± s.d.) of reported habitual energy intake and energy expenditure in (a) 1.5-4.5 year old children (Davies et al, 1994) and (b) non-obese and obese adolescents (Bandini et al, 1990a).


Figure 9
Comparison (± s.d.) of reported habitual energy intake by diet history and weight dietary record and energy expenditure in 3-18 year old subjects (Livingstone et al, 1992b).


Figure 9 Comparison (± s.d.) of reported habitual energy intake by diet history and weight dietary record and energy expenditure in 3-18 year old subjects (Livingstone et al, 1992b).

The results shown in Figures 8-10 indicate that bias in dietary reporting does not operate uniformly across age groups and that it is influenced by the particular methodology used.

In children aged 1.5-4.5 years, mean El calculated by 4-day WDR were not significantly different from mean TEE (+3%) (Figure 8a). Similarly, the mean EI by 7-day WDR of 7 and 9 year olds were in close correspondence with simultaneous measurements of TEE ( + 2%) (Figure 10a), but in adolescents and young adults there was increasing divergence between EI and TEE as age increased: mean EI were significantly lower than TEE in 12 year olds ( - 14%) and in 15 and 18 year olds (-24%, P<0.01) (Figure 10a). Using 14-day estimated intake records, Bandini et al (1990a) also showed a substantial underestimation of EI by adolescents, with the negative bias being most apparent in obese subjects (Figure 8b). After adjustment for changes in body composition, mean estimated EI were 80 ± 23% (non-obese) and 54 ± 32% (obese) of TEE values (P < 0.001).

The age-related discrepancy differed in the study to validate EI by diet history in 3-18 year olds. There was a bias towards overestimation of EI in the younger children by this technique: as age increased, mean differences were + 12%, + 9%, + 11% and - 1% (Figures 9 and 10b)

These validation studies can be criticized because they only involved a small number of subjects in various age groups. However, all of them indicate that a bias in dietary reporting is highly probable. Thus, considerable caution needs to be applied when interpreting energy intake data sets as a basis for deriving energy requirements. Moreover, the magnitude and direction of the errors in children's EI are likely to be different from those found in adults. These biases are highly relevant to the problem of determining appropriate energy intakes for nitrogen balance studies (see Appendix).

Age is an important variable that affects compliance in dietary reporting. The results presented suggest that the mean EI assessed by weighed dietary records are more likely to represent usual food intake in younger than in older subjects. This could be due to the fact that in young children overall control of food intake and responsibility for dietary reporting are shared by parents and other adults concerned with child caring. Younger children also have less unsupervised access to food in- and out-of-home. On the other hand, by early adolescence the responsibility for reporting shifts more to the subjects themselves. Consequently, their greater food requirements in combination with unstructured eating patterns and a significant degree of out-of-home eating suggest that under-reporting (by WDR) may be partly due to forgetfulness and lack of compliance with a demanding protocol.

Obesity is another important factor. In common with obese adults (Prentice et al, 1986), obese adolescents have been found to under-report EI significantly more than their non-obese counterparts (Bandini et al, 1990a). Preoccupation with body weight and image, which may lead to real or apparent dietary restraint, seems to be well developed in girls with normal and low weight by the age of 12 years. Similar, although less marked trends, have been observed in adolescent boys (Livingstone et al, 1992b).

The method used to assess EI also may influence the results. Validation studies with various EI methods across the entire age range of childhood and adolescence are lacking. Only one study has validated simultaneously EI by WDR and DH with TEE (Livingstone et al, 1992b). Although EI by DH were biased towards overestimation in most age groups and individual measurements lacked precision, mean intakes assessed by DH seemed more representative of habitual EI across the age range than WDR. The apparent superiority of DH in overcoming an age-related bias in dietary reporting is contrary to expectations and needs to be evaluated carefully. Since DH is not a standardized instrument and it only measures memory and perception of usual diet, it is subjective and children may tend to exaggerate the intake of 'good' foods and under-estimate 'bad' foods. Accuracy in reporting is also dependent on motivation, intelligence, an adequately developed concept of time, ability to recognize foods, the complexity and stability of food patterns and the age at which children can reliably report their own food intake without control or supervision of adults.

Other factors which are likely to influence reporting accuracy and about which little is known, include social class and educational background.

In addition to the credibility of food intake reports, assessment of EI can be distorted by the use of inadequate food composition tables and/or overlooking the conversion of cooked and processed foods into their raw ingredients2.

2 The world-wide food composition data network being developed by INFOODS offers electronic access to information on prepared and processed foods often not available in local food composition tables (for information: http ://www.crop.cri.nz/crop/infoods/infoods.html).


Figure 10a
Individual differences between energy expenditure measured by the doubly labeled water method and energy intakes as measured by 7-day weighed dietary records expressed as a percentage of energy expenditure in children aged 7 and 9 years (A), 12 years (B) and 15 and 18 years (C).


Figure 10b
Individual differences between energy expenditure measured by the doubly labeled water method and energy intakes as measured by diet history expressed as a percentage of energy expenditure in children aged 3 and 5 years (A), 7 and 9 years (B), 12 years (C) and 15 and 18 years (D) (From data of Livingstone et al, 1992b).

Dietary energy intake data of children and adolescents

A selection of dietary intake studies reported in the literature from about 1980 onwards are reviewed here since earlier studies were evaluated extensively by Ferro-Luzzi & Durnin (1981), as the basis for the 1985 FAO/WHO/UNU estimated requirements. Since 1980, a vast number of dietary intake studies on children and adolescents have been reported and the studies cited in this review are by no means an exhaustive compilation. Many studies were excluded based on the following criteria:

(1) When energy intakes were reported for wide age bands (e.g. 11-16 years) and the mean age was not recorded.
(2) When energy intakes were reported combined for boys and girls over 10 years old.
(3) When data were presented in a format which could not be readily interpreted for the purposes of this review (e.g., in graphs). Unfortunately, many studies in developing countries were excluded for this reason.
(4) When the children studied were generally malnourished or obese, and their mean weight-for-height differed from the NCHS/WHO standards by more than 2 s.d. Many reports were based on representative study populations and therefore included children with a range of body weights.
(5) Only studies of healthy children were included, since many disease states are likely to affect energy intakes and requirements.

Tables 23 and 24 give details of the studies that were reviewed. Forty-eight involved children approximately 110 years old, and 41 studies included children and adolescents approximately 10-18 years old.

Tables 25-30 show the energy intakes of the children, by ascending age. Boys and girls under 5 years are listed together in Table 25, as many studies did not separate the results for each sex. The same is true of the six studies in Table 30. When body weights were not reported, median weights (NCHS) at the mid-point of the age range were assumed and, in Tables 25 and 30, averaged for boys and girls. Energy intake data are presented as absolute values, in relation to body weight, and as multiples of the estimated BMR. The latter were calculated from the mean weights using the equations proposed by Schofield to FAO/WHO/UNU (1985).

Comparison with total energy expenditure and dietary recommendations

When energy intakes are used to assess requirements or to estimate whether the mean intake satisfies a population's dietary recommendations, the possibility of bias must be acknowledged and the data should be analyzed and interpreted accordingly. Information that is incompatible with fundamental principles of energy physiology should not be accepted, as it cannot represent long-term usual intake or is due to methodological bias or inadequate reporting. Goldberg et al (1991) and Black et al (1991) suggested a screening of EI data of adult populations, calculating them as multiples of BMR. For example, a value below 1.27 × BMR, considered as the survival requirement for adults (FAO/ WHO/UNU, 1985), is unacceptable as representative of habitual intake.

Following that logic, we used the PALs shown in Table 21 to establish reasonable limits to evaluate dietary energy surveys among children and adolescents. Mean results lower than two times the coefficient of variation (i.e. 12%) below the PAL corresponding to light habitual activity, or higher than two times the CV above the PAL for heavy habitual activity were considered unlikely to represent the usual intake of healthy children. Since the PALs for boys or girls 6-13 and 14-18 years old in Table 21 are reasonably close, the acceptable limits for those age groups were averaged to simplify the evaluation of the results in Tables 25-30. Further corrections for the energy needs for growth were not made, as they are only about 3% at age 1 and less than 1 % in late adolescence.

Thus, Tables 31-33 were prepared from the data in Tables 25-30 that were between 1.28 and 1.79 × BMR for children 1-5 years, between 1.39 and 2.24 × BMR for boys 6-18, and between 1.30 and 2.10 × BMR for girls 6-18. Mean energy intakes expressed as MJ/d, kJ/kg/d and × BMR, were weighted for the number of children in each study. When a study included more than 500 or 1000 children of a given age and sex, only 30% or 20% of the number, respectively, were used to calculate the weighted means to avoid an extreme bias toward the results of that study.

As Table 31 and Figure 11 show, energy intake per unit of body weight is fairly constant for both boys and girls between 3 and 7 years of age, after which it decreases gradually until age 15 (girls) or 16 (boys).

Compared with total energy expenditure assessed with doubly-labeled water and heart rate monitoring, energy intake tends to overestimate requirements under 8-10 years and to underestimate them after that age. Those trends also apply to the 1985 FAO/WHO/UNU energy recommendations, but the overestimation is markedly higher under 6 years of age. This is partly due to the 5% additional dietary energy recommended in 1985 for children 1-10 years old to accommodate 'a desirable level of physical activity'.

The reported EI of children 1-5 years old is about 13% lower than FAO/WHO/UNU requirements (Figure 11, Table 31). Although the wide range between data sets could reflect real differences in intake, unrepresentative study samples, or artifacts in dietary survey methodology, mean intakes fell short of FAO/WHO/ UNU requirements in about 80% of the data sets.

The influence of sex on dietary energy intake is illustrated in Figure 12 and Tables 31-33. Girls have lower EI than boys, whether expressed in absolute terms or relative to their body weights or their estimated BMR, and the difference becomes greater in adolescence. These findings are consistent with their lower total energy expenditure (Tables 2-7 and 20, and Figure 5).

Conclusions

Recent trends in EI of children and adolescents suggest that if the groups studied are representative of their age and sex, and the EI data are valid measures of habitual intake, then:

(a) Habitual energy intakes of 1-6 year old children are lower than current recommendations. Increasing reported energy intakes by 5% to accommodate a 'desirable level of physical activity' may be unrealistic.
(b) Energy requirements for physical activity may be more variable in adolescent males but lower in the adolescent females, than has been assumed when deriving factorially estimated energy requirements.

For methodological and economic reasons it seems inevitable that we will continue to rely partly on reported EI data as a basis of estimating energy requirements for most populations. However, it is clear that these data can no longer be tacitly accepted as representative of usual intake. Therefore, the following recommendations need to be considered:

(a) At present there are too few studies in which energy intake and energy expenditure have been studied in the same population to know the nature and extent of bias involved in these measurements. This will require more extensive validation studies of energy and nutrient intakes that take into account differences in methodology, social status, education, age, and geographical region in both developing and industrialized countries. From these studies guidelines may emerge for detecting patterns of bias and the characteristics of individuals contributing to it.
(b) Variation among individuals within the same population can be appropriately characterized by a mean and standard deviation whose validity will depend upon the adequacy of the sample. However, the nature and extent of differences in mean values among different populations make it unlikely that they can be appropriately characterized by a single mean and standard deviation, no matter how many populations are sampled. It may be better to express a range of mean values for this purpose.
(c) Research must be done to find ways of minimizing the psychological basis of under- and over-reporting in these age groups.
(d) Appropriate 'cut-off' values based on fundamental principles of energy physiology should be used to determine the acceptance of energy intake results. This will require an extensive data base of basal and total daily energy expenditures (BMR and TEE) in association with objective measures of physical activity. In the meantime, the following estimates of multiples of BMR are suggested as provisional cut-off points: 1-5 years (boys and girls): 1.28-1.79 × BMR; 6-18 years: 1.39-2.24 × BMR (boys) and 1.30-2.10 × BMR (girls).

These recommendations will not guarantee valid data and cannot eliminate the considerable differences among populations, but may lead to the design of more effective instruments for assessing energy intake and requirements of children and adolescents.

Table 23 Dietary surveys of children aged approximately 1-10 years

Source

Country

Sex

Age (y)

No. of subjects

Methoda

Time of year

Socio economic statusb

Urban/ruralc

Race/ethnic background

Bellu et al (1991)

Italy

M & F

1

164

24-h recall

?

?

U

?

Boggio & Klepping (1981)

France

M & F

5-6, 9-11,
14-16

376

7-d weighed record

?

M

U

?

Boulton (1981)

Australia

M & F

2, 3-5,
8-18

198,486, 235

Diet history,
4-d record

12 months

M

U

Mixed

Brault-Dubuc & Mongeau (1989)

Canada

M & F

6-16

402 (L)d

7-d record

12 months

M

U

?

Catassi et al (1988)

Italy

M & F

0.5-2.5

90

3-d weighed record

?

?

?

?

Cunningham & Lee (1990)

Republic of Ireland

M & F

8-18

538

Diet history

12 months

M

U & R

Caucasian

Davies et al (1994)

United Kingdom

M & F

1.5-4.5

81

4-d weighed record

Autumn

M

U

?

Deheeger et al (1991)

France

M & F

2

323

5-d record, diet history

?

M

U

?

Duggan et al (1991)

United Kingdom

M & F

0.3-3.3

97

5-d weighed record

?

L

U

Asian

Durnin (1984)

United Kingdom

M & F

5-6,
10-11

430

5-d weighed record

?

M

U

?

Eastwood et al (1990)

Mexico

M & F

2.8-3.9,
4.0-5.0

45

1-d weighed record

?

L

R

Mixed

Griffiths et al (1987)

United Kingdom

M & F

3-4

37

7-d weighed record & duplicate analysis

?

?

?

?

Hagman et al (1986)

Sweden

M & F

2-3, 4-5,
8-9, 13-14

1020

7-d record, diet history, 24-h recalls

12 months

M

U & R

?

Hitchcock et al (1984)

Australia

M & F

1-3

205 (L)e

7-d record

12 months

M

U

?

Ho et al (1988)

China

M & F

5-6

60

7-d weighed record

?

M

U

Chinese

Hoffmans et al (1986)

Netherlands

M & F

0.3-1.5

124 (L)f

24 h-recall

Spring

M

U

?

Ikemoto et al (1989)

Japan

M & F

1-2

10

Chemical analysis

12 months

?

?

?

Jenner et al (1988)

Australia

M & F

8-10

884

Food frequency questionnaire

April - Aug

M

U

?

Knuiman et al (1983)

Finland,
Netherlands,
Italy,
Phillipines
and Ghana

M

8-9

589

7-d record or 7-d recall

Feb May

M

U & R

Mixed

Livingstone et al (1992b)

United Kingdom

M & F

3-18

78

7-d weighed record, diet history

Oct-July

M

U & R

Causasian

Leung et al (1984)

Canada

M & F

3-4

189

4-d record

?

M

U

?

Lopez-Jaramillo et al (1992)

Ecuador

M

9

114

2 × 24 h recalls

?

LU

U

Ecuadorian

Magarey & Boulton (1984)

Australia

M & F

4

178

3-d record

June Sept

M

U

Mixed

Martinez (1982)

Canada

M & F

6-7

193

3-d record

?

M

U & R

?

McKillop & Durnin (1982)

United Kingdom

M & F

1-2

143

5-d weighed record

?

M

U

?

Morgan & Zabik (1981)

USA

M & F

5-12

657

7-d record

Autumn

-

-

-

Morrison et al (1980)

USA

M & F

6-19

949

24-h recall

12 months

M

U

Black & White

Nelson et al (1990)

United Kingdom

M & F

7-12

194

7-d weighed record

April-July

?

U & R

?

Narasinga et al (1983)

India

M & F

2-6

128

Diet questionnaire

12 months

U

?

Asian

Neiderud et al (1992)

Sweden & Greece

M & F

2-8

152

24-h recall

Aug-Nov

?

U & R

Mixed

Oliveria et al (1992)

USA

M & F

3-5

91

4 × 3-d record

12 months

M

U

Caucasian

Palti et al (1979)

Israel

M & F

2.5-4

98 (L)g

24-hr recall

December - April

M

U

Mixed

Pao et al (1985)

USA

M & F

1-18

2826

24-h recall, 2-d record

Spring

M

U & R

Mixed

Parizkova et al (1986)

Czechoslovakia

M & F

3-5

22

7-d record

?

?

U

?

Paul et al (1990)

United Kingdom

M & F

1-3

48 (L)h

7-d weighed record

?

M

?

?

Payne & Belton (1992)

United Kingdom

M & F

2-5

153

7-d weighed record

May-April

M

U & R

?

Persson & Calgren (1984)

Sweden

M & F

4-5, 8-9

477

7-d record

?

M

?

?

Räsänen et al (1985)

Finland

M & F

3-18

1251

24-h recall

Autumn

M

U & R

?

Räsänen et al (1991)

Finland

M & F

9-18

1200

2 × 24-h recalls

Autumn

M

U & R

?

Räsänen & Ylonen (1992)

Finland

M & F

1.5

46

3-d record

August-November

M

U

?

Salas et al (1990)

Spain

M & F

2-9

121

2 × 24-h recall

?

M

U

Caucasian

Salz et al (1993)

USA

M & F

6-9

195

24-h recall

?

M

U & R

Caucasian

Sawaya et al (1988)

Saudi Arabia

M & F

1.1-2.0, 2.1-3.0, 3.1-4.0, 4.1-5.0

540

24-h recall

?

?

U-R1

Arab

Sunnegardh et al (1986)

Sweden

M & F

8-9, 13-14

666

24-h recall, 7-d record, diet history

?

M

U & R

?

Treiber et al (1990)

USA

M & F

3-5

55

2 × 24-h recall

?

M

U

Black and White

Vanderkooy et al (1987)

Canada

M & F

4-5

108

3-d weighed record

May-Sept

MU

U & R

Caucasian

Van Steenbergen (1984)

Kenya

M & F

1-3, 4-6

56

2-d weighed record

wet & dry

L

R

Akamba

Walker et al (1990)

Jamaica

M & F

0.75-2.0

191

4 × 24-h recall

?

L

U

Jamaican, black

a Records = estimated (household measures) records, weighed records = weighed intake.
b Socioeconomic status: M = mixed, L = lower, LU = lower and upper, MU = middle and upper, U = upper.
c Urban/Rural: U = urban, R = rural.
d L = longitudinal Brault-Dubuc & Mongeau (1984): 402 children studied in two cohorts starting at age 6 and 10 years with yearly measurements made for 7 years.
e Hitchcock et al (1984): 205 children recruited. Measurements made at 1 year (n = 125), 1½ years (n = 142), 2 years (n = 146) and 3 years (n = 145).
f Hoffmans et al (1986): 124 children studied. Measurements made at 16 months and 28 months.
g Palti et al (1979): 98 children studied. Three measurements made (1st study n = 98; 2nd study n = 82; 3rd study n = 75).
h Paul et al (1990): 48 children recruited at 2 months. Measurements made at 12 months (n = 29), 15 months (n = 25), 18 months (n = 22), 24 months (n = 22) and 36 months (n = 31).
i Described by authors as semi-rural.

Table 24 Dietary surveys of children and adolescents aged approximately 10-18 years

Source

Country

Sex

Age (y)

No. of subjects

Methoda

Time of year

Socio economic statusb

Urban/ruralc

Race/ethnic background

Adamson et al (1992)

United Kingdom

M & F

11-12

379

2 × 3-d records

January-July

M

U & R

?

Baghurst et al (1983)

Australia

M & F

14-15, 18

490

Food frequency

?

M

U

Mixed

Barber et al (1985)

Great Britain

F

15-18

448

14-d diary

?

?

U

Caucasian

Bergstrom et al (1993)

Sweden

M & F

13-16, 16-18

731

7-d record

Sept-December
January-May

M

U & R

?

Boulton (1981)

Australia

M & F

2
3-5
8-18

198
486
235

Record and diet history 4-d record 4-d record

12 months
12 months
12 months

M

U

Mixed

Boggio & Klepping (1981)

France

M & F

5-6, 9-11, 14-16

376

7-d weighed record

?

M

U

?

Brault-Dubuc & Mongeau (1989)

Canada

M & F

6-17

402
(L)d

7-d record

12 months

M

U

?

Bull (1985)

United Kingdom

M & F

15-18

382

14-d record

Spring-Summer

M

U & R

?

Crawley (1993)

United Kingdom

M & F

16-17

4760

4-d record

April-July

M

U & R

?

Cunningham & Lee (1990)

Republic of Ireland

M & F

8-18

538

Diet history

12 months

M

U & R

Caucasian

Department of Health (1989)

United Kingdom

M & F

10-11, 14-15

2697

7-d weighed record

January-June

M

U & R

?

Durnin (1984)

United Kingdom

M & F

5-6, 10-11

430

5-d weighed record

?

M

U

?

Frank et al (1985)

USA

M & F

10-11, 13-14

491

24-h recall

?

?

?

Black & White

Greger et al (1978)

USA

F

12-13

184

Diet recalls, diet history

Autumn & Spring

?

?

?

Hagman et al (1986)

Sweden

M & F

2-3, 4-5, 8-9, 13-14

1020

7-d record, diet history, 24-h recalls

12 months

M

U & R

?

Hackett et al (1984)

United Kingdom

M & F

11-14

375

5 × 3-d records

?

M

U & R

?

Jenner et al (1992)

Australia

M & F

11-12

1215

2-d records

April-August

M

U

?

Johnson & Jensen (1984)

USA

M & F

10-11

60

7-d records, 24-h recalls

?

M

?

Mixed

Kaufman et al (1982)

Israel

M & F

17-18

1178

24-h recall

?

M

U

Mixed

Livingstone et al (1992b)

United Kingdom

M & F

3-18

78

7-d weighed record, diet history

October-July

M

U & R

Caucasian

McCoy et al (1984)

USA

F

12, 14, 16

1247

2 × 24-h recalls

February-May

M

U & R

Black & White

Michaud et al (1991)

France

M & F

15-19

481

1-d record

?

M

U

?

Morgan & Zabik (1981)

USA

M & F

5-12

657

7-d record

Autumn

MU

?

?

Morrison et al (l980)

USA

M & F

6-19

949

24-h recall

12 months

M

U

Black & White

Nelson et al (1990)

United Kingdom

M & F

7-12

194

7-d weighed record

April-July

?

U & R

?

Pao et al (1985)

USA

M & F

1-18

2826

24-h recall, 2-d record

Spring

M

U & R

Mixed

Perusse et al (1984)

Canada

M & F

11-17

580

3-d weighed record

?

?

U & R

?

Post et al (1987)

Netherlands

M & F

12-18

233

Diet history

Jan-April

MU

U

?

Räsänen et al (l985)

Finland

M & F

3-18

1768

2 × 24-h recalls

Autumn

M

U & R

?

Räsänen et al (1991)

Finland

M & F

9-18

1200

2 × 24-h recalls

Autumn

M

U & R

?

Rodriguez (1991)

Guatemala

M

10-11

140

3 × 24-h recalls

July-Sept

LM

U

Mixed

van den Reek et al (1986)

USA

F

12-15

8

7-d weighed duplicate method

Summer

U

U

White

Seone & Roberge (1983)

Canada

M & F

10-18

500

3-d weighed record

?

?

?

?

Skinner et al (1985)

USA

M & F

16-18

225

24-h recall

?

?

U & R

Black & White

Story (1986)

USA

M & F

13 17

277

3 × 24-h recall

?

L

R

Cherokee

Strain et al (1994)

United Kingdom

M & F

12-13, 15-16

1016

Diet history

12 months

M

U & R

Caucasian

Sunnegardh et al (1986)

Sweden

M & F

8-9, 13-14

666

24-h recall, Diet history, 7-d record

?

M

U & R

?

Tan et al (1989)

New Zealand

M & F

12-14

501

3 × 24-h recalls

Autumn

M

U

?

Tayter et al (1989)

USA

M & F

10-12

39

3 d-record

?

M

?

Caucasian

Torun et al (1993)

Guatemala

M

10-12

24(L)e

3 × 24 h recalls every 3 months

12 months

L

U

Mixed

Woodward et al (1984)

Tasmania

M & F

12-16

1055

1-d diet record

?

M

U & R

?

a Records = estimated (household measures) records, weighed records = weighed intake.
b Socioeconomic status: M = mixed, L = lower, LU = lower and upper, MU = middle and upper, U = upper.
c Urban/Rural: U = urban, R = rural.
d L-Longitudinal. Brault-Dubuc & Mongeau (1989): 402 children studied in two cohorts starting at age 6 and 10 years with yearly measurements made for 7 years.
e Torun et al (1994): 24 girls studied four times at 3-month intervals.

Table 25 Energy intakes of children aged approximately 1-5 years







Energy intake (El)




Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age (y)

N

Mean

s.d.

BMRa (MJ/d)

Mean

s.d.

Mean

s.d.

x BMRb

Bellu et al (1991)

1

164

9.81

1.28

2.26

4.15

1.29

423

131

1.84c



(76M, 88F)









Catassi et al (1988)

1-1.25

12

10.75

1.4

2.50

4.11

0.99

382

92

1.64


1.25-1.50

10

11.90

1.0

2.79

4.12

0.65

349

55

1.48


1.50-2.00

18

12.30

1.7

2.90

4.21

0.93

344

76

1.45

Davies et al (1993)

1.5-2.5

23

12.85

1.67

3.04

4.20

0.63

327

49

1.38

Duggan et al (1991)

1-1.5

13

11.00

(M)d

2.57

3.89e

1.26

354

115

1.51


1.5-2.0

9

11.00

(M)

2.57

3.71

1.06

337

96

1.44

Hitchcock et al (1984)

1

62 (M)

11.0

(M)

2.57

4.15

0.85

377

77

1.55



63 (F)

11.0

(M)

2.57

3.98

0.83

362

75

1.93c


1.5

72 (M)

11.0

(M)

2.57

4.96

0.89

451

81

1.74



70 (F)

11.0

(M)

2.57

4.47

1.00

406

91

1.56

Hoffmans et al (1986)

1-2

124

11.2

-

2.62

4.08

1.06

366

107

1.56

Ikemoto et al (1989)

1-2

10

11.0

1.6

2.57

3.90

0.41

377

40

1.52

McKillop & Durnin (1982)

1-2

73 (M)

11.6

-

2.72

4.79

1.02

413

-

1.76



70 (F)

10.9

-

2.56

4.59

0.96

420

-

1.79

Pao et al (1985)

1-2

246

11.0

(M)

2.57

4.90

1.43

445

130

1.91c

Paul et al (1990)

1.0

15 (M)

10.00

1.23

2.31

3.72

0.60

370

60

1.61


1.0

14 (F)

9.07

0.98

2.09

3.39

0.48

370

50

1.62


1.25

13 (M)

10.37

1.07

2.41

3.90

0.77

380

50

1.62


1.25

12 (F)

9.70

0.68

2.25

3.63

0.46

370

50

1.73


1.50

11 (M)

10.87

1.47

2.53

4.02

0.93

370

70

1.59


1.50

11 (F)

10.45

1.00

2.44

3.68

0.61

350

60

1.51

Räsänen & Ylonen (1992)

1-2

23 (M)

11.0

(M)

2.57

5.20

0.83

473

75

2.02c



23 (F)

11.0

(M)

2.57

4.57

0.92

415

84

1.78



46 (Total)

11.0

(M)

2.57

4.89

0.93

445

85

1.90c

Sawaya et al (1988)

1.1-2

178

11.15

-

2.62

3.62

-

325

-

1.38

Van Steenbergen (1984)

1-3

22

12.25


2.90

4.16

1.74

340

142

1.44

Walker et al (1990)

0.75-2

129 stunted

8.43


1.92

3.99

1.87

473

213

2.07c


0.75-2

62 non-stunted

11.45


2.69

4.07

1.50

356

130

1.51

Boulton (1981)

2.0

102 (M)

12.94

1.67

3.06

5.08

0.99

400

80

1.66



95 (F)

12.65

2.91

3.00

4.73

1.03

390

90

1.58



197 (Total)

12.78

2.69

3.02

5.02

1.86

400

140

1.66

Catassi et al (1988)

2.0 2.5

18

14.90

3.3

3.56

4.53

0.93

307

63

1.27c

Davies et al (1994)

2.5-3.5

31

14.96

1.40

3.57

4.64

0.74

310

49

1.30

Deheeger et al (1991)

2.0

131 (M)

12.1

1.6

2.85

5.51

1.34

452

110

1.93c



192 (F)

12.2

1.9

2.87

5.85

1.08

480

89

2.04c

Duggan et al (1991)

2-3.25

10

13.5

(M)

3.20

4.35

1.62

322

120

1.36

Eastwood et al (1990)

2.75 3.9

45

15.05


3.49

6.48

1.66

430

1.85c


Hagman et al (1986)

2-3

41 (M)

15.1

-

3.61

5.80

-

384

-

1.61



41 (F)

15.4

-

3.70

5.55

-

360

-

1.50

Hitchcock et al (1984)

2

74 (M)

13.5

(M)

3.20

5.35

1.01

396

75

1.67



72 (F)

13.5

(M)

3.22

4.85

1.17

359

87

1.51

Hoffmans et al (1980)

2-3

124

13.8

-

3.28

4.74

1.39

344

107

1.45

Narasinga et al (1993)

2-3

9 (M)

13.4

-

3.18

5.44

-

407

-

1.71



10 (F)

11.7

-

2.76

4.72

-

403

-

1.71

Neiderud et al (1992)

2-3

11 Greek Imm

13.5

(M)

3.20

6.08

-

450

-

1.90c



13 Swedish

13.5

(M)

3.20

4.99

-

370

-

1.56



20 Greek

13.5

(M)

3.20

5.63

-

417

-

1.76

Palti et al (1979)

2.5

98

13.2

-

3.12

4.58

13.38

347

105

1.47

Paul et al (1990)

2.0

13 (M)

12.20

1.20

2.87

4.22

0.78

350

60

1.47



9 (F)

11.61

0.83

2.74

4.03

0.50

350

40

1.47

Payne & Belton (1992)

2-3

31 (M)

14.0

1.5

3.33

4.50

0.76

321

54

1.35



42 (F)

13.5

1.4

3.22

4.39

0.83

325

61

1.36

Salas et al (1990)

2-5

61

15.0

(M)

3.48

6.68

1.39

445

93

1.92c

Sawaya et al (1988)

2.1-3

97

13.25

-

3.32

4.06

-

306

-

1.22c

Davies et al (1994)

3.5-4 5

27

16.94

2.10

3.66

5.42

0.64

320

38

1.48

Eastwood et al (1990)

2.8-3.9

45

15.05

-

3.49

6.48

1.66

430

-

1.85c

Griffiths et al (1987)

3-4

15 (M)

16.0

2.0

3.58

4.60

0.82

289

42

1.28



22 (F)

15.4

1.5

3.52

5.48

1.07

360

71

1.56

Hitchcock et al (1984)

3-4

73 (M)

16.5

(M)

3.62

5.74

1.00

348

61

1.59



72 (F)

16.5

(M)

3.63

5.55

0.94

336

57

1.53

Leung et al (1984)

3-4

189

16.5

(M)

3.62

5.80

1.20

352

73

1.60

Livingstone et al (1992b)

3-4

8

16.4

1.5

3.61

5.91

0.55

360

34

1.64

Narasinga et al (1983)

3 4

23 (M)

14.9

-

3.47

6.33

-

425

-

1.82c



13 (F)

15.0

-

3.49

5.81

-

387

-

1.66

Oliveria et al (1992)

3-5

55 (M)

16.5

(M)

3.62

6.71

0.95

407

58

1.85c



36 (F)

16.5

(M)

3.63

6.14

1.23

372

75

1.69



91 (Total)

16.5

(M)

3.62

6.48

1.10

393

67

1.79

Palti et al (1979)

3

82

14.1

-

3.40

5.09

1.25

360

89

1.50

Pao et al (1985)

3-5

404

16.5

(M)

3.62

5.99

1.62

363

98

1.65

Paul et al (1990)

3

20 (M)

14.53

1.56

3.44

4.96

0.78

340

50

1.44



13 (F)

14.16

1.35

3.41

4.62

0.50

330

50

1.35

Parizkova et al (1986)

3-5

22

19.3

2.50

3.89

7.25

2.03

376

105

1.86c

Payne & Belton (1992)

3-4

31 (M)

16.3

1.6

3.60

5.01

0.89

307

55

1.39



38 (F)

15.4

1.7

3.52

4.76

0.71

309

46

1.35

Räsänen et al (1985)

3-4

153 (M)

15.7

(median)f

3.55

6.40

1.70

408

108

1.80c



128 (F)

15.2

(median)f

3.50

5.80

1.20

382

79

1.66

Sawaya et al (1988)

3.1-4

158

15.4

-

3.53

4.62

-

300

-

1.31

Treiber et al (1990)

3-5

66

16.35

-

3.62

6.84

1.78

418

-

1.89c

Eastwood et al (1990)

4.0-5.0

22

17.25

-

3.71

6.30

1.19

365

-

1.70

Hagman et al (1986)

4-5

154 (M)

18.8

-

3.84

6.90

-

367

-

1.80c



152 (F)

18.6

-

3.82

6.45

-

347

-

1.69

Magaray & Boulton (1984)

4-5

93 (M)

17.9

-

3.76

5.94

-

331

-

1.58



85 (F)

17.7

-

3.74

5.44

-

307

-

1.45

Narasinga et al (1983)

4-5

17 (M)

17.3

-

3.70

6.62

-

383

-

1.79



6 (F)

15.6

-

3.54

5.90

-

378

-

1.67

Palti et al (1979)

4

75

16.5

-

3.62

4.96

0.95

301

58

1.37

Payne & Belton (1992)

4-5

35 (M)

18.0

1.9

3.77

5.30

0.79

294

44

1.41



30 (F)

17.6

2.2

3.73

5.06

0.89

288

51

1.36

Persson & Calgren (1984)

4-5

Total sample of 477

16.5

(M)

3.62

6.67

1.23

404

75

1.84c



(including 8-9 y)









Sawaya et al (1988)

4.1-5

107

17.25

-

3.71

4.93

-

286

-

1.33

Vanderkooy et al (1987)

4-5

62 (M)

18.6

-

3.82

6.23

1.64

335

57

1.63



44 (F)

18.0

-

3.77

5.38

1.47

299

53

1.43

Van Steenbergen (1984)

4-6

34

18.2

-

3.79

5.04

2.03

277

111

1.33

a BMR = Predicted basal metabolic rate (FAO/WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c Excluded from Table 31 because x BMR was < 1.28 or > 1.79.
d (M) = Median (NCHS) weights at mid-year.
e Mean energy intakes (MJ/d) calculated from recorded energy intake (kJ/kg/d) and median (NCHS) weights.
f Median weights reported.

Table 26 Energy intakes of boys aged approximately 5-10 years








Energy intake





Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age
(y)

N

Mean

s.d.

BMRa
(MJ/d)

Mean

s.d.

Mean

s.d.

× BMRb

Boggio & Klepping (1981)

5-6

51

19.5

2.2

3.91

6.89

1.12

353

57

1.76

Durnin (1984)

5-6

93

19.5

(Median)c

3.91

6.90

-

354

-

1.76

Livingstone et al (1992b)

5-6

6

17.9

2.5

3.76

6.57

0.83

367

46

1.75

Narasinga et al (1983)

5-6

12

17.4

-

3.71

6.63

-

381

-

1.79

Brault-Dubuc & Mongeau (1989)

6-7

102

20.6

2.52

4.01

8.91

1.73

438

99

2.22

Martinez (1982)

6 7

89

22.4

-

4.18

8.03

2.05

358

92

1.92

Morrison et al (1980)

6-9

95 (white)d

23.8

(M)e

4.31

8.10

2.51

340

105

1.88



35 (black)

23.8

(M)

4.31

6.97

2.90

293

122

1.62

Räsänen et al (1985)

6-7

139

21.6

(M)

4.11

7.90

1.90

366

88

1.92

Salz et al (1983)

6-9

102

25.8

-

4.50

8.27

2.22

321

101

1.84

Brault-Dubuc & Mongeau (1989)

7-8

84

22.9

3.1

4.23

9.04

1.84

401

95

2.14

Livingstone et al (1992b)

7-8

6

25.4

6.6

4.46

9.75

1.93 (WDR)f

384

76

2.19






4.46

9.41

1.50 (DH)

370

59

2.11

Nelson et al (1990)

7-10

25

27.0

(M)

4.62

7.59

1.43

281

31

1.64

Boulton (1981)

8-9

17

31.9

-

5.08

8.93

1.81

280

60

1.76

Brault-Dubuc & Mongeau (1989)

8-9

98

25.4

3.7

4.46

9.43

1.73

375

63

2.11

Hagman et al (1986)

8-9

144

27.3

-

4.64

8.90

-

326

-

1.92

Jenner et al (1988)

8-10

434

30.1

-

4.91

7.45

1.80

248

60

1.52

Knuiman et al (1983)

9

133 (Finland)

30.0

5.0

4.90

9.25

1.63

310

54

1.89


9

117 (Netherlands)

30.0

5.0

4.90

8.75

1.38

293

46

1.79


9

109 (Italy)

30.0

7.0

4.90

9.25

2.13

310

71

1.89


9

114 (Philippines)

22.0

3.0

4.14

7.98

1.93

364

88

1.93


9

116 (Ghana)

24.0

3.0

4.33

7.10

1.40

297

59

1.64

Lopez-Jaramillo et al (1992)

9

78 (LSC)g

25.5

-

4.47

5.20

1.15

204

45

1.16i



36 (USC)

27.0

-

4.62

6.43

0.96

238

36

1.39

Sunnegardh et al (1986)

8-9

159

27.3

3.8

4.64

8.40

2.50
(24-h R)h

308

92

1.81



142

27.3

3.8

4.64

8.90

1.20 (DR)

326

44

1.92

Boulton (1981)

9.11

23

31.6

-

5.05

8.85

1.15

280

60

1.75

Brault-Dubuc & Mongeau (1989)

9-10

103

27.8

3.9

4.69

9.74

1.91

355

77

2.08

Livingstone et al (1992b)

9-10

6

30.2

8.4

4.92

8.95

1.36 (WDR)

296

45

1.82






4.92

9.94

1.38 (DH)

329

46

2.02

Räsänen et al (1985)

9-10

162

29.9

(M)

4.89

9.10

2.30

304

77

1.86

Räsänen et al (1991)

9-10

119

27.0

(M)

4.89

8.30

2.40

307

89

1.70

a BMR = Predicted basal metabolic rate (FAO/WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c Median weight report.
d White = white children, black = black children.
e (M) = Median (NCHS) weights at mid-year.
f WDR = weighed dietary record, DH = diet history.
g LSC = lower social class, USC = upper social class.
b 24-h R = 24-h recall, DR = diet records (estimated from household measures).
i Excluded from Table 31 because × BMR was < 1.39.

Table 27 Energy intakes of girls aged approximately 5-10 years








Energy intake





Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age
(y)

N

Mean

s.d.

BMRa (MJ/d)

Mean

s.d.

Mean

s.d.

× BMRb

Boggio & Kleping (1981)

5-6

52

19.2

2.5

3.88

6.62

1.19

345

62

1.71

Durnin (1984)

5-6

110

18.4

(Median)c

3.80

6.00

-

326

-

1.58

Livingstone et al (1992a,b)

5-6

6

18.1

2.2

3.78

6.54

0.64

361

35

1.73

Narasinga et al (1983)

5-6

9

16.9

-

3.66

5.91

-

350

-

1.61

Brault-Dubuc & Mongeau (1989)

6-7

93

19.0

2.7

3.86

7.86

1.51

416

84

2.04

Martinez (1982)

6-7

104

21.6

-

4.10

7.28

1.38

337

64

1.78

Morrison et al (1980)

6-9

79 (white)d

23.8

(M)e

4.31

8.11

2.34

341

98

1.88



37 (black)

23.8

(M)

4.31

6.08

2.64

255

111

1.41

Räsänen et al (1985)

6-7

145

20.5

(M)

4.00

6.80

1.30

332

63

1.70

Salz et al (1983)

6-9

93

25.6

-

4.48

7.87

2.12

308

87

1.76

Brault-Dubuc & Mongeau (1989)

7-8

73

21.0

2.81

4.05

8.25

1.43

398

82

2.04

Livingstone et al (1992a,b)

7-8

6

23.5

2.2

4.28

6.62

0.82 (WDR)f

282

35

1.55






4.28

7.56

1.20 (DH)

322

51

1.77

Nelson et al (1990)

7-10

26

27.0

(M)

4.61

6.92

1.39

256

51

1.50

Boulton (1981)

8-9

17

29.8

-

4.87

7.74

1.12

260

30

1.59

Brault-Dubuc & Mongeau (1989)

8-9

95

23.4

4.8

4.27

8.21

1.37

358

80

1.92

Hagman et al (1986)

8-9

152

28.7

-

4.77

7.85

-

274

-

1.65

Jenner et al (1988)

8-10

450

29.3

-

4.83

6.92

1.85

236

63

1.43

Sunnegardh et al (1986)

8-9

167

28.6

6.6

4.76

7.70

2.60 (24-h R)g

269

91

1.62



153

28.6

6.6

4.76

8.00

1.20 (DR)

280

42

1.68

Boulton (1981)

9-11

24

34.6

-

5.32

7.62

2.06

220

70

1.43

Brault-Dubuc & Mongeau (1989)

9-10

94

26.6

4.6

4.57

8.38

1.43

321

65

1.83

Livingstone et al (1992a)

9-10

6

32.2

3.6

5.10

7.95

1.26 (WDR)

247

39

1.56






5.10

8.63

0.43 (DH)

268

13

1.69

Räsänen et al (1985)

9-10

154

30.3

(M)

4.92

7.70

-

254

-

1.57

Räsänen et al (1991)

9-10

109

27.0

(M)

4.92

7.80

2.20

289

81

1.59

a BMR = Predicted base; metabolic rate (FAO/WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c Median weight reported.
d White = white children, black = black children.
e (M) = Median (NCHS) weights at mid-year.
f WDR = weighed dietary record, DH = diet history.
g 24-h R = 24-h recall, DR = diet records (estimated from household measures).

Table 28 Energy intakes of boys aged approximately 10-18 years







Energy intake (EI)





Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age
(y)

N

Mean

s.d.

BMRa
(MJ/d)

Mean

s.d.

Mean

s.d.

× BMRb

Boggio & Klepping (1981)

9-11

37

31.3

4.5

4.99

8.34

1.04

266

33

1.67

Brault-Dubuc & Mongeau (1989)

10

104

31.4

5.5

5.00

10.58

2.20

344

80

2.12

Cunningham & Lee (1990)

8-12

85

34.1

-

5.20

9.70

3.20

284

94

1.87

Department of Health (1989)

10-11

902c

36.8

7.7

5.40

8.67

1.51

236

41

1.61

Durnin (1984)

10-11

102

33.0

(Median)d

5.11

8.40

-

255

-

1.64

Frank et al (1985)

9-11

184

35.0

-

5.26

9.80

-

280

-

1.86

Morrison et al (1980)

10-12

101 (white)e

34.5

(M)f

5.23

10.15

3.68

294

107

1.94


10-12

31 (black)

34.5

(M)

5.23

8.33

4.13

241

120

1.59

Pao et al (1985)

9-11

196

31.0

(M)

4.99

8.29

2.41

267

-

1.66

Rodriguez (1991)

10-11

140

34.2

8.0

5.22

7.38

1.92

222

59

1.41

Seone & Roberge (1983)

10-12

99

35.8

-

5.32

9.08

1.69

254

47

1.71

Tayter et al (1989)

10-12

20

35.3

-

5.30

9.18

-

260

-

1.73

Adamson et al (1992)

11-12

184

40.5

-

5.67

8.61

1.76

213

-

1.52

Hackett et al (1984)

11-12

193

39.0

5.56

8.90

-

229

-


1.60

Boulton (1981)

11-12

8

39.0

-

5.56

8.57

2.02

220

80

1.54

Brault-Dubuc & Mongeau (1989)

11-12

96

34.6

6.76

5.24

10.26

2.06

305

60

1.96

Jenner et al (1992)

11-12

626c

42.0

-

5.78

8.60

2.30

205

55

1.49

Nelson et al (1990)

11-12

76

37.0

(M)

5.41

7.74

1.67

209

45

1.43

Perusse et al (1984)

11-17

304

49.8

14.7

6.34

11.00

2.91

221

58

1.74

Boulton (1981)

12-13

15

42.7

-

5.83

10.25

1.78

240

70

1.76

Brault-Dubuc & Mongeau (1989)

12-13

79

37.6

6.8

5.45

10.63

1.87

290

50

1.95

Cunningham & Lee (1990)

12-15

93

49.3

-

6.31

11.30

3.30

229

67

1.79

Livingstone et al (1992b)

12-13

6

44.5

6.7

5.96

10.15

1.08 (WDR)g

228

24

1.70






5.96

11.82

2.64 (DH)

266

59

1.98

Pao et al (1985)

12-14

296

44.0 (M)

5.92

9.49

2.91

216

-


1.60

Post et al (1987)

12-13

26

38.4

-

5.51

11.70

2.55

305

66

2.12

Räsänen et al (1991)

12-13

116

40.9

(M)

5.69

10.20

3.60

249

88

1.79

Strain et al (1994)

12-13

251

43.0

9.4

5.85

11.0

(Median)

256

-

1.88

Tan et al (1989)

12-14

246

44.0

(M)

5.92

10.2

2.9

232

66

1.72

Woodward et al (1984)h

12-13

132h

41.0

(Median)

5.70

9.9

(Median)

241

-

1.74

Boulton (1981)

13-14

12

52.6

-

6.55

10.0

2.54

190

30

1.53

Brault-Dubuc & Mongeau (1989)

13-14

61

42.6

7.2

5.82

10.70

2.05

257

48

1.84

Frank et al (1985)

13-14

78

49.8

-

6.34

11.03

-

221

-

1.74

Hagman et al (1986)

13-14

166

50.5

-

6.40

12.10

-

240

-

1.89

Morrison et al (1980)

13-15

94 (white)

49.8

(M)

6.34

12.06

5 55

242

111

1.90




40 (black)

49.8 (M)

6.34

10.87

5.08

218

102

1.72

Post et al (1987)

13-14

73

43.4

-

5.88

11.60

1.71

267

39

1.97

Sunnegardh et al (1986)

13-14

171

49.8

11.8

6.34

10.8

3.9 (24-h R)i

217

78

1.70



166



6.34

12.3

3.9 (DH)

247

78

1.94

Seone & Roberge (1983)

13-15

103

52.5

-

6.54

10.91

2.23

208

42

1.67

Story (1986)

13-17

139

66.4

-

7.58

9.57

4.94

144

75

1.26i

Woodward et al (1984)

13-14

132

48.0

(Median)

6.21

11.70

(Median)

244

-

1.88

Baghurst & Record (1983)

14-15

77

52.6

(M)

6.55

11.95

-

227

-

1.82

Bergstrom et al (1993)

14-16

155

54.3

10.2

6.67

8.90

2.20

164

41

1.33j

Boulton (1981)

14-16

25

62.3

-

7.26

11.84

3.24

190

60

1.63

Boggio & Klepping (1981)

14-16

73

56.7

12.2

6.96

10.94

2.56

193

45

1.57

Brault-Dubuc & Mongeau (1989)

14-15

49

50.0

8.8

6.36

11.60

2.46

238

49

1.82

Department of Health (1989)

14-15

513c

55.7

9.5

6.77

10.40

2.30

187

41

1.54

Post et al (1987)

14-15

95

48.9

-

6.28

12.20

1.95

249

40

1.94

Woodward et al (1984)

14-15

132

54.0

(Median)

6.65

12.10

(Median)

224

-

1.82

Brault-Dubuc & Mongeau (1989)

15-16

46

57.0

8.34

6.87

12.29

2.84

218

50

1.79

Bull (1985)

15-18

198

62.0

(M)

7.23

10.10

-

163

-

1.40

Cunningham & Lee (1990)

15-18

73

63.9

-

7.37

14.0

4.5

219

70

1.90

Livingstone et al (1992a,b)

15-16

6

56.4

9.1

6.83

11.33

1.88 (WDR)

201

33

1.66






6.83

13.91

2.20 (DH)

247

39

2.04

Michaud et al (1991)

15-19

198

63.7

8.5

7.36

12.39

3.80

195

60

1.68

Pao et al (1985)

15-18

365

61.9

(M)

7.23

10.92

3.55

176

57

1.51

Post et al (1987)

15-16

102

55.6

-

6.77

12.5

3.03

225

54

1.85

Räsänen et al (1985)

15-16

139

58.0

(M)

6.94

11.8

3.70

203

64

1.70

Räsänen et al (1991)

15-16

118

58.0

(M)

6.94

11.8

4.30

203

74

1.70

Strain et al (1994)

15-16

252

59.0

9.4

7.01

13.10

(Median)

222

-

1.87

Woodward et al (1984)

15-16

132

60.0

(Median)

7.09

11.9

(Median)

198

-

1.68

Bergstrom et al (1993)

16-18

211

66.4

8.4

7.55

10.50

2.70

158

41

1.39

Boulton (1981)

16-17

15

65.8

-

7.51

11.84

4.35

180

60

1.50

Brault-Dubuc & Mongeau (1989)

16-17

29

59.8

8.25

7.07

11.72

3.02

198

51

1.66

Crawley (1993)

16-17

2006e

62.7

(M)

7.31

11.40

2.69

182

43

1.56

Morrison et al (1980)

16-19

82 (white)

64.0

(M)

7.37

13.20

4.25

207

67

1.79



14 (black)

64.0

(M)

7.37

13.11

5.57

205

87

1.78

Post et al (1987)

16-17

76

61.0

-

7.16

12.80

3.49

210

57

1.79

Seone & Roberge (1983)

16-18

69

63.9

-

7.37

12.31

2.82

193

44

1.67

Skinner et al (1985)

16-18

114

64.0

(M)

7.38

12.80

5.20

200

81

1.73

Kaufman et al (1982)

17-18

627c

61.3

-

7.18

10.38

3.91

169

64

1.45

Post et al (1987)

17-18

28

63.8

-

7.36

13.00

3.17

204

50

1.77

Livingstone et al (1992b)

18-19

5

78.5

14.1

7.83

10.72

3.46 (WDR)

137

44

1.37j






7.83

15.52

2.26 (DH)

198

29

1.98

Räsänen et al (1985)

18-19

124

65.0

(M)

7.45

12.50

3.20

192

49

1.68

Räsänen et al (1991)

18-19

93

65.0

(M)

7.45

12.50

3.80

192

58

1.68

a BMR = Predicted basal metabolic rate (FAO/WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c Only 30% (for n > 500) or 20% (for n > 1000) used to calculate weighted means in Table 32.
d Median values reported.
e White = white children, black = black children.
f (M) = Median weight for height from Baldwin's standards (FAO/WHO/UNU, 1985).
g WDR = Weighted dietary record, DH = diet history.
h Woodward et al (1984). Total sample size = 1055. Sample sizes for specific groups were not reported but are assumed to be evenly distributed by age group (n = 4) and sex.
i 24-hr R = 24-h recall.
j Excluded from Table 32 because × BMR was < 1.39.

Table 29 Energy intakes of girls aged approximately 10-18 years







Energy intake (El)





Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age
(y)

N

Mean

s.d.

BMRa
(MJ/d)

Mean

s.d.

Mean

s.d.

× BMRb

Boggio & Klepping (1981)

9-11

38

31.0

5.0

4.68

7.38

1.53

238

49

1.58

Brault-Dubuc & Mongeau (1989)

10

103

30.9

6.8

4.68

9.02

1.99

300

79

1.93

Cunningham & Lee (1990)

8-12

63

34.7

-

4.87

8.40

2.80

242

81

1.72

Department of Health (1989)

10-11

821c

37.1

7.4

4.99

7.69

1.61

207

43

1.54

Durnin (1984)

10-11

125

34.4

Mediand

4.86

7.70

-

224

-

1.58

Frank et al (1985)

9-11

159

35.0

-

4.89

8.64

-

247

-

1.77

Morrison et al (1990)

10-12

103 (white)f

36.0

(M)e

4.94

8.85

2.90

246

81

1.79


10-12

44 (black)

36.0

(M)

4.94

7.10

4.02

197

112

1.44

Pao et al (1985)

9-11

222

32.0

(M)

5.08

7.69

2.03

240

-

1.51

Seone & Roberge (1983)

10-12

72

37.4

-

5.01

7.91

1.70

211

45

1.58

Tayter et al (1989)

10-12

19

37.0

-

5.01

7.86

-

212

-

1.57

Torun et al (1994)

10-12

72

29.59

3.55

4.63

6.42 (24-h R)g

1.56

218

53

1.39







5.97 (FFQ)

1.76

204

61

1.29h

Adamson et al (1992)

11-12

195

41.9

-

5.24

8.25

1.95

197

-

1.57

Hackett et al (1984)

11-12

212

39.9


5.14

8.27

-

207

-

1.61

Boulton (1981)

11-12

15

41.8

-

5.23

7.53

3.02

180

40

1.44

Brault-Dubuc & Mongeau (1989)

11-12

85

34.5

7.2

4.86

9.16

1.96

274

57

1.88

Jenner et al (1992)

11-12

589c

42.9

-

5.29

7.50

2.10

175

49

1.42

Nelson et al (1990)

11-12

67

38.7

(M)

5.08

7.45

1.20

193

31

1.47

Pérusse et al (1984)

11-17

276

46.4

11.2

5.47

8.47

2.57

183

47

1.55

Boulton (1981)

12-13

7

49.9

-

5.64

6.98

1.61

140

70

1.24h

Brault-Dubuc & Mongeau (1989)

12-13

71

38.9

7.2

5.09

9.55

1.93

253

50

1.88

Cunningham & Lee (1990)

12-15

114

51.7

-

5.74

9.10

3.0

176

58

1.59

Greger et al (1978)

12-13

183 (fall)

48.0

12.0

5.55

8.46

2.45

176

51

1.52



184 (spring)

52.0

30.0

5.75

8.08

2.35

155

45

1.41

Livingstone et al (1992a,b)

12-13

6

44.8

3.9

5.39

8.57

1.59 (WDR)i

191

35

1.59






5.39

12.08

1.47 (DH)

270

33

2.24h

McCoy et al (1984)

12-13

441

44.0

(M)

5.35

8.43

-

192

-

1.58

Pao et al (1985)

12-14

295

46.5

(M)

5.47

7.76

2.58

167

-

1.42

Post et al (1987)

12-13

31

42.2

-

5.25

9.80

1.67

232

40

1.87

Räsänen (1985)

12-13

166

44.0

(M)

5.35

8.20

2.30

186

52

1.53

Räsänen (1991)

12-13

119

44.0

(M)

5.35

8.50

2.60

193

59

1.59

Van den Reek (1986)

12-15

8

47.0

9.0

5.50

6.20

1.94

132

41

1.13h

Strain et al (1994)

12-13

259

44.0

9.0

5.35

9.2

(Median)

209

-

1.72

Tan et al (1989)

12-14

255

46.5

(M)

5.47

7.8

2.1

168

45

1.43

Woodward et al (1984)

12-13

132j

43.0

(Median)

5.29

8.9

(Median)

207

-

1.68

Boulton (1981)

13-14

15

62.4

-

6.28

7.49

2.04

120

40

1.19h

Brault-Dubuc & Mongeau (1989)

13-14

50

44.0

7.99

5.35

9.08

1.62

213

37

1.70

Frank et al (1985)

13-14

70

48.6

-

5.58

8.35

-

172

-

1.50

Hagman et al (1986)

13-14

170

50.3

-

5.67

9.65

-

192

-

1.70

Morrison et al (1980)

13-15

78 (white)

49.3

(M)

5.61

8.55

2.68

173

54

1.52



32 (black)

49.3

(M)

5.61

7.83

2.78

159

56

1.40

Post et al (1987)

13-14

98

48.0

-

5.55

9.60

1.98

200

41

1.73

Seone & Roberge (1983)

13-15

92

50.5

-

5.68

8.61

1.63

170

32

1.52

Sunnegardh et al (1986)

13 14

169

50.9

9.2

5.70

8.10

2.60 (24-h R)

159

51

1.42






5.70

9.90

2.60 (DH)

194

51

1.74

Story (1986)

13-17

138

62.8

-

6.32

7.57

2.89

120

46

1.20h

Woodward et al (1984)

13-14

132

49.0

(Median)

5.60

9.00

(Median)

184

-

1.61

Baghurst et al (1983)

14-15

69

51.4

(M)

5.72

9.36

-

182

-

1.64

Bergstrom et al (1993)

14-16

189

53.7

8.2

5.84

7.10

1.60

132

30

1.22h

Boulton et al (1981)

14-16

27

57.5

-

6.03

6.90

1.84

120

30

1.14h

Boggio & Klepping (1981)

14-16

125

51.2

7.50

5.71

8.48

1.97

166

38

1.49

Brault-Dubuc & Mongeau (1989)

14-15

37

48.3

7.30

5.56

8.96

2.31

191

48

1.61

Department of Health (1989)

14-15

461

53.7

9.20

5.84

7.85

1.74

146

32

1.34

McCoy et al (1984)

14-15

440

51.4

(M)

5.72

8.40

-

163

-

1.47

Post et al (1987)

14-15

129

52.0

-

5.75

9.60

2.27

185

44

1.67

Woodward et al (1981)

14-15

132

51.0

(Median)

5.70

9.2

(Median)

180

-

1.61

Barber et al (1985)

15-18

448

56.4

-

6.00

8.6

-

152

-

1.43

Brault-Dubuc & Mongeau (1989)

15-16

32

49.9

4.98

5.64

9.16

2.17

187

43

1.62

Bull (1985)

15-18

184

53.8

(M)

5.84

7.80

-

145

-

1.34

Cunningham et al (1990)

15-18

110

57.2

-

6.02

8.90

2.50

156

44

1.48

Livingstone et al (1992b)

15-16

6

57.2

9.2

6.02

6.84

1.78 (WDR)

120

31

1.14h






6.02

9.34

1.70 (DH)

163

30

1.55

Michaud et al (1991)

15-19

283

54.6

6.2

5.88

8.40

2.73

154

50

1.43

Pao et al (1985)

15-18

374

53.8

(M)

5.84

7.39

2.73

137

51

1.27h

Post et al (1987)

15-16

130

54.9

-

5.90

9.50

2.28

173

42

1.61

Räsänen et al (1985)

15-16

152

53.0

(M)

5.80

7.60

2.20

143

42

1.31

Räsänen et al (1991)

15-16

112

53.0

-

5.80

8.60

3.30

162

62

1.48

Strain et al (1994)

15-16

254

57.0

8.5

6.01

9.10

(Median)

160

-

1.51

Woodward et al (1984)

15-16

132

52.0

(Median)

5.75

8.50

(Median)

163

-

1.48

Bergstrom et al (1993)

16-18

176

58.4

8.7

6.08

7.10

1.90

122

33

1.17h

Boulton (1981)

16-17

12

55.9

-

5.95

6.15

1.41

110

30

1.03h

Brault-Dubuc & Mongeau (1989)

16-17

18

52.0

5.60

5.75

9.11

2.18

178

42

1.58

Crawley (1993)

16-17

2754c

54.0

(M)

5.85

8.80

2.10

163

39

1.50

Morrison et al (1980)

16-19

71 (white)

54.0

(M)

5.85

8.68

3.41

161

63

1.48



13 (black)

54.0

(M)

5.85

8.10

5.00

150

93

1.38

Post et al (1987)

16-17

99

57.4

-

6.03

9.30

1.99

162

35

1.54

Seone & Roberge (1983)

16-18

65

54.4

-

5.87

7.96

2.18

146

40

1.36

Skinner et al (1985)

16-18

111

54.0

(M)

5.85

8.60

3.77

159

70

1.47

Kaufman et al (1992)

17-18

551c

55 7

_

5.94

6.71

2.89

120

52

1.13h

Post et al (1987)

17-18

32

57.9

-

6.05

9.80

2.83

169

49

1.62

Livingstone et al (1992b)

18-19

5

63.9

16.2

5.98

7.84

1.74 (WDR)

123

27

1.31






5.98

10.13

1.58 (DH)

159

25

1.69

Räsänen et al (1985)

18-19

148

54.4

-

5.87

7.70

2.50

142

46

1.31

Räsänen et al (1991)

18-19

116

54.4

-

5.87

7.40

2.50

136

46

1.26h

a BMR = Predicted basal metabolic rate (FAO WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c Only 30% (for n > 500) or 20% (for n > 1000) used to calculate weighted means in Table 33.
d Median values reported.
e (M) = Median weight for height from Baldwin's standards [FAO/WHO/UNU, 1985]
f White = white children, black = black children.
g 24-h R = 24-hour recall, FFQ = food frequency questionnaire.
h Excluded from Table 33 because × BMR was < 1.30 or > 2.10.
i WDR = weighed dietary record, DH = diet history.
j Woodward et al (1981). Total sample size = 1055. Sample sizes for specific groups were not reported but are assumed to be evenly distributed by age group (n = 4) and sex.

Table 30 Combined energy intakes for male and female subjects aged 5-10 years







Energy intake





Weight (kg)


(MJ/d)

(kJ/kg/d)


Source

Age (y)

N

Mean

s.d.

BMRa
(MJ/d)

Mean

s.d.

Mean

s.d.

× BMRb

Ho et al (1988)

5-6

60

17.5

-

3.73

5.36

-

312

-

1.44

Morgan & Zabik (1981)

5-6

162

20.5

(M)c

4.00

8.09

-

395

-

2.02

Pao et al (1985)

6-8

428

22.4

(M)

4.18

7.17

1.89

320

-

1.72

Salas et al (1990)

6-9

60

23.8

(M)

4.31

8.63

1.60

363

67

2.00

Morgan & Zabik (1981)

7-8

168

23.6

(M)

4.29

8.75

-

371

-

2.04

Persson & Calgren (1984)

8-9

(Total sample of 477 including 4-5 olds)

27.6

(M)

4.67

8.22

1.56

298

57

1.76

Morgan & Zabik (1981)

9-10

165

30.1

(M)

4.91

9.30

-

309

-

1.89

a BMR = Predicted basal metabolic rate (FAO WHO/UNU, 1985).
b Mean energy intakes expressed as a multiple of mean predicted BMR.
c (M) = Median (NCHS) weights at mid-year (FAO/WHO/UNU, 1985).

Table 31 Energy intakes of subjects (sexes combined) aged 1-5 years, and of boys and girls aged 5-10 years compared with current FAO/WHO/UNU (1985) estimated requirements




Energy intakea







(MJ/d)

(kJ/kg/d)

(kcal/kg/d)

× BMR

FAO/WHO/UNU (1985) requirements

Percentage difference (%)b

Age (y)

Studies n

Subjects n

Mean

s.d.

Mean

s.d.

Mean

s.d.

Mean

(MJ/d)

(kJ/kg/d)

(MJ/d)

(kJ/kg/d)

Sexes combined

1-2

12

927

4.17

0.82

375

74

90

18

1.54

4.80

439

- 13.1

- 14.6




(Range 3.39-4.96)

(Range 325-451)



(Range 1.38-1.79)





2-3

11

835

4.92

1.08

367

81

88

19

1.51

5.70

418

-13.7

-12.2




(Range 4.03-5.80)

(Range 310-407)



(Range 1.30-1.76)





3-5

22

2460

5.76

1.15

345

67

82

16

1.53

6.50

397

-11.4

-13.1




(Range 4.60-6.90)

(Range 277-408)



(Range 1.31-1.80)





Boys

5-6

6

273c

7.06

1.05

363

53

87

13

1.80

7.57

385

- 6.7

- 5.7




(Range 5.36-8.09)

(Range 312-395)



(Range 1.44-2.02)





6-7

4

544

7.82

1.88

360

87

86

21

1.90

7.94

368

-1.5

-2.2




(Range 7.17-8.91)

(Range 320-438)



(Range 1.92-2.22)





7-8

6

436

8.41

2.29

352

100

84

24

1.94

8.32

347

+ 1.1

+ 1.4




(Range 6.97-9.58)

(Range 293-401)



(Range 1.62-2.14)





8-9

7

996

8.13

1.79

289

62

69

15

1.72

8.66

322

-6.1

- 10.2




(Range 7.45-9.43)

(Range 248-375)



(Range 1.64-2.11)





9-10

7

1085

8.75

1.81

314

66

75

16

1.83

8.99

301

-2.7

+4.3




(Range 7.10-9.74)

(Range 280-364)



(Range 1.64-2.08)





Girls

5-6

6

288

6.64

0.96

349

50

83

12

1.72

6.81

368

-2.5

-5.2




(Range 5.36-8.09)

(Range 312-395)



(Range 1.44-2.02)





6 7

4

556

7.21

1.52

342

66

82

16

1.78

7.11

347

+1.4

-1.4




(Range 6.80-7.86)

(Range 320-416)



(Range 1.70-2.04)





7-8

6

402

8.05

2.13

343

93

82

22

1.88

7.40

318

+8.8

+7.9




(Range 6.08-8.25)

(Range 255-398)



(Range 1.41-2.04)





8-9

7

1026

7.47

1.69

266

62

64

15

1.58

7.65

268

-2.4

-0.7




(Range 6.92-8.21)

(Range 236-358)



(Range 1.50-1.92)





9-10

6

469

8.14

1.75

283

67

68

16

1.68

7.86

259

+3 6

+9.3




(Range 7.62-8.38)

(Range 220-321)



(Range 1.43-1.83)





a Energy intake data (MJ/d, kJ/kg/d, × BMR) expressed as weighted means. s.d. estimated from


(n = number of studies). For studies where s.d. was not reported the mean CV of other studies in that group was assumed.

b Percentage difference = (energy intake - FAO/WHO/UNU estimated requirement)/estimated requirement × 100.
c Sample sizes for 5-10 year olds include studies listed in Table 30 and assume equal numbers of boys and girls.

Table 32 Energy intakes of boys aged 10-18 years compared with current FAO/WHO/UNU (1985) estimated requirements




Energy intakea










(MJ/d)

(kJ/kg/d)

(kcal/kg/d)

× BMR

FAO/WHO/UNU (1985) requirements

Percentage difference (%)b

Age (y)

Studies n

Subjects n

Mean

s.d.

Mean

s.d.

Mean

s.d.

Mean

(MJ/d)

(kJ/kg/d)

× BMR

(MJ/d)

(kJ/kg/d)

× BMR

10-11

10

1981

8.86

2.62

255

76

61

18

1.68

8.95

278

1.76

-1.0

-8.3

-4.5




(Range 7.38-10.58)

(Range 222-344)



(Range 1.41-2.12)







11-12

7

1203

8.74

1.97

220

58

53

14

1.55

9.37

254

1.73

-6.7

-13.4

-10.4




(Range 7.74-10.26)

(Range 205-305)



(Range 1.43-1.96)







12-13

9

1167

10.47

2.59

240

61

57

15

1.76

9.66

237

1.69

+8.4

+1.3

+4.1




(Range 9.49-11.0)

(Range 216-305)



(Range 1.60-2.12)







13-14

10

1023

11.37

3.28

233

64

56

15

1.80

10.20

217

1.67

+11.5

+7.4

+7.2




(Range 10.00-12.10)

(Range 190-267)



(Range 1.53-1.97)







14-15

8

1268

11.11

2.50

208

50

50

12

1.70

10.83

206

1.65

+2.6

+0.1

+2.4




(Range 10.40-12.20)

(Range 187-249)



(Range 1.54-1.94)







15-16

7

795

12.34

3.25

212

57

51

14

1.75

11.29

195

1.62

+9.3

+8.7

+8.0




(Range 11.33-13.10)

(Range 198-225)



(Range 1.66-1.87)







16-17

10

3143

11.49

3.51

184

55

44

13

1.57

11.71

187

1.60

-1.9

-1.6

-1.9




(Range 10.10-14.00)

(Range 163-219)



(Range 1.40-1.90)







17-18

5

968

11.22

3.53

179

56

43

13

1.55

12.00

184

1.60

-6.5

-2.7

-3.1




(Range 10.38-13.20)

(Range 169-207)



(Range 1.45-1.79)







a Energy intake data (MJ/d, kJ/kg/d, × BMR) expressed as weighted means. s.d. estimated from


(n = number of studies). For studies where s.d. was not reported the mean CV of other studies in that group was assumed.
b Percentage difference = (Energy intake - FAO/WHO/UNU estimated requirement)/estimated requirement × 100.

Table 33 Energy intakes of girls aged 10-18 years compared with current FAO/WHO/UNU (1985) estimated requirements




Energy intakea










(MJ/d)

(kJ/kg/d)

(kcal/kg/d)

× BMR

FAO/WHO/UNU (1985) requirements

Percentage difference (%)b

Age (y)

Studies n

Subjects n

Mean

s.d.

Mean

s.d

Mean

s.d.

Mean

(MJ/d)

(kJ/kg/d)

× BMR

(MJ/d)

(kJ/kg/d)

× BMR

10-11

9

1750

7.94

2.46

226

72

54

17

1.60

7.99

237

1.65

-0.6

-4.6

-3.0




(Range 7.09-9.02)

(Range 197-300)



(Range 1.44-1.93)







11-12

8

1254

7.81

2.16

194

45

46

11

1.51

8.28

215

1.63

-5.7

-9.8

-7.4




(Range 6.54-9.16)

(Range 175-274)



(Range 1.41-1.88)







12-13

11

2142

8.41

2.16

186

53

44

13

1.55

8.57

196

1.60

-1.9

-5.1

-3.1




(Range 7.80-9.80)

(Range 168-253)



(Range 1.42-1.88)







13-14

9

1005

8.88

2.39

179

48

43

11

1.58

8.87

181

1.58

0.0

-1.1

0.0




(Range 7.83-9.65)

(Range 159-213)



(Range 1.40-1.73)







14-15

8

1669

8.47

2.19

166

42

40

10

1.49

9.03

176

1.57

-6.2

-5.7

-5.1




(Range 7.85-9.60)

(Range 146 191)



(Range 1.34-1.67)







15-16

7

818

8.72

2.39

161

45

38

11

1.48

8.95

169

1.54

-2.6

-4.7

-3.9




(Range 7.60-9.50)

(Range 143-187)



(Range 1.31-1.62)







16-17

8

3789

8.62

2.53

156

46

37

11

1.46

8.91

166

1.53

-3.3

-6.0

-4.6




(Range 7.80-9.30)

(Range 145-178)



(Range 1.34-1.58)







17-18

3

399

8.55

3.32

156

61

37

15

1.45

8.95

165

1.52

-4.4

-5.4

-4.6




(Range 8.10-9.80)

(Range 150-169)



(Range 1.38-1.62)







a Energy intake data (MJ/d, kJ/kg/d, × BMR) expressed as weighted means. s.d. estimated from


(n = number of studies). For studies where s.d. was not reported the mean CV of other studies in that group was assumed.
b Percentage difference = (energy intake - FAO/WHO/UNU estimated requirement)/estimated requirement × 100.


Figure 11a
Energy intake compared with expenditure estimated by doubly labeled water and heart rate monitoring, including stunted and underweight children, and current recommendations: boys (solid line: mean energy intake; interrupted line: FAO/WHO/UNU recommendations).


Figure 11b
Energy intake compared with expenditure estimated by doubly labeled water and heart rate monitoring, including stunted and underweight children, and current recommendations: girls (solid line: mean energy intake; interrupted line: FAO/WHO/UNU recommendations).


Figure 12
Comparison of average dietary energy intakes of boys and girls.

General conclusions and recommendations

1. Dietary recommendations to satisfy the energy requirements of children and adolescents should be based on their energy expenditure and requirements for growth. Their habitual physical activity and lifestyle must be taken into account, as energy expenditure should be consistent with the attainment and maintenance of long-term good health, and the performance of economically necessary and socially desirable physical activity.

Energy for socially desirable activities is particularly important as part of the normal process of a child's development, for activities such as exploration of the surroundings, learning and behavioural adjustments to other children and adults (FAO/ WHO/UNU, 1985).

2. There is a major contrast between lifestyles of children and adolescents in rural developing societies and in developed countries. Whereas the former engage in physically-demanding obligatory or occupational activities from an early age, the latter tend to be quite sedentary (Cooper et al, 1984; Verschuur & Kemper, 1985; Atomi et al, 1986; Armstrong et al, 1990; Gortmaker et al, 1990). Discretional activities are also probably quite different in those two settings: in developing rural areas, children walk more to move around and to socialize, while those in developed countries travel in motor vehicles and spend a significant period of time sitting and watching television (Dietz and Gortmaker, 1985; Gortmaker et al, 1990).

More studies are needed in children and adolescents who live in cities of developing countries. Available evidence suggests that those in the middle and upper socioeconomic groups are relatively sedentary, with a lifestyle that resembles that of children in developed countries more than that of their rural counterparts. Habitual activities related to energy expenditure in the lower socioeconomic groups have hardly been studied.

3. Recommendations to fulfill energy requirements of children and adolescents should be made according to two or three levels of intensity of habitual physical activity, in a manner similar to that recommended for adults in the 1985 FAO/WHO/UNU Report. Provisional physical activity levels are suggested in Table 21.

4. The 1985 recommendation for 5% additional dietary energy intake to 'allow a desirable level of physical activity' among all children under 10 years of age seems unwarranted. Furthermore, scientific evidence accumulated in the last decade suggests that current FAO/WHO/UNU recommendations for dietary energy are too high for children under 5, and possibly under 7, years of age.

5. Current recommendations seem somewhat low for adolescent boys and for girls around puberty. This is more so in rural areas of the developing world, where recommendations for girls throughout adolescence and for boys and girls of school age may also be too low when expressed per unit of body weight or as multiples of BMR.

6. Healthy but stunted or slightly underweight boys and girls in developing countries seem to have a higher energy requirement per unit of body weight than their well-nourished, non-stunted counterparts. The differences in absolute terms and PAL units are less consistent. It seems reasonable to recommend for them the same total dietary energy intakes as for well-nourished, non-stunted children of the same age and sex, provided that they are encouraged and have opportunities to be physically active.

7. Dietary energy recommendations must be accompanied by strong recommendations for physical activity compatible with the achievement and maintenance of health, prevention of obesity and adequate social and psychological development. The minimum amount of exercise required by children for a healthy life has not been exactly determined. Provisional recommendations can be made, similar to those for adults, based on Simons-Morton et al's (1988) review of recommendations for physical activity for children: exercise involving dynamic movement of large muscle groups for at least 20 min, three or more times a week, at an intensity that raises and maintains heart rate at 140 or more beats per minute.
There are some contradictory and non-conclusive results on the role of physical activity for the prevention of obesity, but as Gortmaker et al (1990) point out, obesity seems to have a stronger relationship with inactivity than with vigorous physical activity.

Methodological considerations

8. The use of doubly-labeled water provides, at present, the most exact quantitative measurements of TEE of free-living children and adolescents. However, financial and technical constraints limit its application in samples large enough to represent boys and girls of all ages living in a wide variety of social and geographic settings. Minute-by-minute heart rate monitoring techniques seem promising for this purpose, especially if they are validated in the field with doubly-labeled water measurements.

9. Time-motion or activity diary techniques can provide useful information to confirm or monitor the accuracy of dietary recommendations. Sampling must be adequate in size, physiological and anthropological characteristics, and appropriate factors must be applied to quantify the energy expended in the observed/recorded/timed activities. These techniques also provide an important insight on the pattern of habitual activities of children and adolescents.

10. There is a need to obtain more information on the energy cost of activities and tasks in which children and adolescents from different societies typically engage, in order to increase and improve existing databases (e.g. Torun, 1990a). Standardized procedures must be established to define those activities and tasks and to measure their energy cost.

11. Time allocation studies can help to define the appropriate level of habitual physical activity for specific (geographic, ethnic, social) groups of children and adolescents. There is, however, a need to develop standardized procedures for the collection of time allocation data in different societies across all age groups.

12. The use of multiples of BMR, or physical activity levels (PAL), is useful in physiological and practical terms to calculate the energy expenditure and estimate the energy requirements of population groups. PALs for children and adolescents with different lifestyles have been suggested in this paper.

13. It seems that a single set of mathematical equations cannot be used across all races and geographic regions to calculate the ]BMR of boys or girls of a specific age group. To avoid making important errors in the estimation of energy requirements and recommendations, this issue must be cleared. If necessary, specific sets of mathematical equations should be derived for some races or countries.

14. Dietary energy intake studies tend to overestimate energy requirements of children under 8 and to underestimate those of children over 12 years of age. Nevertheless, they may be useful to estimate requirements of a healthy, well growing population when total energy expenditure cannot be measured or calculated. However, to accept the data as representative of habitual and appropriate intake, it is necessary that it should be: (a) derived from adequate population samples; (b) validated by studies that take into account the method used for data collection, as well as the anthropological, geographic and health characteristics of the population and (c) screened and edited to exclude information that is incompatible with fundamental principles of energy physiology in population groups (e.g. exclusion of data below or above cut-off points compatible with long-term habitual eating patterns of a healthy population). Provisional cut-off points, calculated as multiples of BMR, are suggested in this paper.

Other conclusions and recommendations

15. Other specific conclusions, including recommendations for important and much needed research, are included at the end of each section in this document.

References

Acharya M & Bennett L (1981): The rural women of Nepal: an aggregate analysis and summary of 8 village studies. Kathmandu: Centre for Economic Development and Administration.

Adamson A, Rugg-Gunn A, Butter T. Appleton D & Hackett A (1992): Nutritional intake, height and weight of 11 to 12-year-old Northumbrian children in 1990 compared with information obtained in 1980. Br. J. Nutr. 68, 543-563.

Andersen KL, Masironi R. Rutenfranz J & Seliger (1978): Habitual physical activity and health. World Health Organization Regional Office for Europe, Copenhagen: WHO Regional Publication, European Series No. 6.

Armstrong N. Balding J. Gentle P & Keiby B (1990): Patterns of physical activity among 11 to 16 year old British children. Br. Med. J. 301, 203-205.

Atomi Y. Iwaoka K, Hatta H. Miyashita M & Yamamoto Y (1986): Daily physical activity levels in preadolescent boys related to VO2 max and lactate threshold. Eur. J. Appl. Physiol. 55, 156-161.

Baghurst Kl & Record SJ (1983): Intake and sources, in selected Australian subpopulations, of dietary constituents implicated in the etiology of chronic diseases. J. Fd Nutr. 40, 1-15.

Bandini L, Schoeller DA, Cyr HN & Dietz WH, Jr (1990a) Validity of reported energy intake in obese and non-obese adolescents. Am. J. Clin. Nutr. 52, 415421.

Bandini LG, Schoeller DA & Dietz WH, Jr (1990b) Energy expenditure in obese and non-obese adolescents. Pediatr. Res. 27,198-203.

Banerjee B & Saha N (1972): Energy intake and expenditure of Indian schoolboys. Br. J. Nutr. 27, 483-490.

Barber SA, Bull NL (1985): Food and nutrient intakes by British women aged 1525 years with particular reference to dieting habit and iron intakes. Ecol. Fd. Nutr. 16,161-169.

Bellu R. Ortisi, MT, Incerti P. Mazzoleni V, Martinoli G. Agostini C, Galluzzo C, Riva E & Giovannini M (1991): Nutritional survey on a sample of one-year-old infants in Milan: intake of macro nutrients. Nutr. Res. 11,1221-1229.

Bergstrom E, Hernell O & Persson LA (1993): Dietary changes in Swedish adolescents. Acta Paediatr. 82, 472-480.

Berio AJ (1984): The use of time allocation data in developing countries: From influencing development policies to estimating energy requirements. Paper prepared for the International Research Group on Time Budgets and Social Activities, Helsinki, Finland.

Black AE, Goldberg GR. Jebb SA, Livingstone M B E, Cole TJ & Prentice AM (1991): Critical evaluation of energy intake data using fundamental principles of energy physiology 2: evaluating the results of published surveys. Eur. J. Clin. Nutr. 45, 583-599.

Boggio V & Klepping J (1981): Caractéristiques de la ration alimentaire de l'enfant. Arch. Fr. Paediatr. 38, 679-686.

Bouchard C, Tremblay A, Leblanc C, Lortie G. Savard R & Theriault G (1983): A method to assess energy expenditure in children and adults. Am.J. Clin. Nutr. 37, 461-467.

Boulton J (1981): Nutrition in childhood and its relationship to early somatic growth, body fat, blood pressure and physical fitness. Acta Paediatr. Scand., Suppl. 284, 1-85.

Bradfield RB, Paulos J & Grossman L (1971): Energy expenditure and heart rate of obese high school girls. Am. J. Clin. Nutr. 24, 1482-1488.

Brault-Dubuc M & Mongeau E (1989): Energy intake of Montreal school-age children. J. Can. Diet. Assoc. 50,107-112.

Bull NL (1985): Dietary habits of 15 to 25-year-olds. Hum. Nutr. Appl. Nutr. Suppl. 39A, 1-68.
Cain M (1977): The economic activities of children in a village in Bangladesh. Popul. Dev. Rev. 3, 201-227.

Carbañero, TA (1980): 'The shadow price' of children in Philippine rural households. Master's thesis. University of the Philippines, Quezon City. In Rural household studies in Asia, eds H Binswanger et al. Kent Ridge Singapore, Singapore University Press.

Catassi C, Guerrieri A, Natalini G, Oggiano N, Coppa GV & Giorgi PL (1988): Computerized dietary analysis in children aged 6-30 months 1: method of the survey and energy intake. Riv. Ital. Ped. (IJP) 14, 702-706.

Ceesay SM, Prentice AM, Day KC, Murgatroyd PR, Goldberg GR & Scott W (1989): The use of heart-rate monitoring in the estimation of energy expenditure using whole body calorimetry: a validation study. Br. J. Nutr. 61, 175-186.

Colfer CJ (1981): Women, men and time in the Forest of East Kalimantan. East-West Environment and Policy Institute. Reprint No. 25.

Cooper R, Allen A, Goldberg R, Trevisan M, van Horn L, Liu K, Steinhauer M, Rubenstein A & Stamler J (1984): Seventh-day adventist adolescents-life-style patterns and cardiovascular risk factors. Prev. Med. 149, 471-477.

Crawley HF (1993): The energy, nutrient and food intakes of teenagers aged 16-17 years in Britain. Br. J. Nutr. 70, 15-26.

Cunningham K & Lee P (1990): The Irish National Nutrition Survey 1990. Dublin: The Irish Nutrition and Dietetic Institute.

Davies PSW, Livingstone MBE, Prentice AM, Coward WA, Jagger SE, Stewart C, Strain JJ & Whitehead RG (1991): Total energy expenditure during childhood and adolescent. Proc. Nutr. Soc. 50, 14A.

Davies PSW, Coward WA, Gregory J, White A & Mills A (1994): Total energy expenditure and energy intake in the pre-school child: a comparison. Br. J. Nutr. 72, 13-20.

Deheeger M, Rolland-Cachera MF, Pequignot, Labadie MD, Rossignol C & Vinit F (1991): Evolution de l'alimentation des enfants âgés de 2 ens entre 1973 et 1986. Ann. Nutr. Metab. 35, 132-140

Department of Health (1989): The diets of British schoolchildren. Reports of health and social subjects 36. London: HMSO.

Dietz WH, Jr & Gortmaker SL (1985): Do we fatten our children at the television set? Obesity and television viewing in children and adolescents. Pediatrics 75, 807-812.

Dresen MHW, de Groot G, Brandt Corstius JJ, Krediet GHB & Meijer MGH (1982): Physical work capacity and daily physical activities of handicapped and non-handicapped children. Eur. J. Appl. Physiol. 48, 241-251.

Duggan MB, Steel G, Elwys G, Harbottle L & Noble C (1991): Iron status, energy intake and nutritional status of healthy young Asian children. Arch. Dis. Child. 66, 1386-1389.

Durnin JVGA (1990): Methods to assess physical activity and the energy expended for it by infants and children. In Activity, energy expenditure and energy requirements of infants and children, eds B Schürch & NSS Scrimshaw, pp 45-55. Lausanne: International Dietary Energy Consultancy Group.

Durnin JVGA (1971): Physical activity of adolescents. Acta Paediat. Scand., Suppl. 217, 133-135.

Durnin JVGA (1984): Energy balance in childhood and adolescents. Proc. Nutr. Soc. 3, 271-279.

Eastwood Garcia S, Kaiser LL, Dewey KG (1990): Self regulation of food intake among rural Mexican preschool children. Eur. J. Clin. Nutr. 44, 371-380.

Elia M (1992): Energy expenditure in the whole body. In: Energy metabolism: determinants and cellular corollaries, eds JM Kinney & HN Tucker, pp 19-59. New York: Raven Press.

Emons HJG, Groenenboom DC, Westerterp KR & Saris WHM (1992): Comparison of heart rate monitoring combined with indirect calorimetry and the doubly labelled water (2H218O) method for the measurement of energy expenditure in children. Eur. J. Appl. Physiol. 65, 99-103.

FAO/WHO/UNU (1985): Energy and protein requirements. WHO Technical Report Series 724. Geneva: World Health Organization.

Ferro-Luzzi A & Durnin JVGA (1981): The assessment of human energy intake and expenditure: a critical review of the recent literature. Rome: FAO (Document ESN: FAO/WHO/UNU/EPR/81/

Fironzbakhsh S, Mathis RK, Dorchester WL, Oseas RS, Groncy PK Grant KE & Finkelstein JZ (1993): Measured resting energy expenditure in children. J. Pediatr. Gastroenterol. Nutr. 16, 136-142.

Fontvielle AM, Harper IT, Ferraro RT, Spraul M & Ravussin R (1993): Daily energy expenditure by five-year-old children, measured by doubly labeled water. J. Pediatr. 123, 200-207.

Frank GC, Farris RP, Cresenta JL, Webber LS & Berenson GS (1985): Dietary trends of 10- and 13-year-old children in a biracial community: the Bogalusa Heart Study. Prev. Med. 14,123-139.

Franklin D & Harrell MW (1985): Resource allocation decisions in low-income rural households. Fd Policy (May): 100-108.

Griffiths M, Rivers JPW & Payne PR (1987): Energy intake in children at high and low risk of obesity. Hum. Nutr. Clin. Nutr. 41C, 425-430.

Gilliam TB, Freedson PS, Geenen DL & Shaharay B (1981): Physical activity patterns determined by heart rate monitoring in 6 to 7-year-old children. Med. Sci. Sports Exer. 13, 65-75.

Goldberg GR, Black AK, Jebb SA, Cole TJ, Murgatroyd PR, Coward WA & Prentice AM (1991): Critical evaluation of energy intake data using fundamental principles of energy physiology: 1. Derivation of cut-off values to identify under-recording. Eur. J. Clin. Nutr. 45, 569-581.

Goran Ml, Carpenter WH & Poehlman ET (1993): Total energy expenditure in 4 to 6-year-old children. Am. J. Physiol. 264, E706-E711.

Gortmaker SL, Dietz WH Jr & Cheung LWY (1990): Inactivity, diet and the fattening of America. J. Am. Diet. Assoc. 90, 1247-1252.

Greger JL, Higgins MM, Abernathey RP, Kirksey A, DeCorso MB & Baligar P (1978): Nutritional status of adolescent girls in regard to zinc, copper and iron. Am. J. Clin. Nutr. 31, 269-275.

Grossman LS (1984): Peasants, subsistence ecology, and development in the highlands of Papua New Guinea. Princeton, New Jersey: Princeton University Press.

Guzman MP. Cabrera JP, Yuchingtat GP, Almero EM, Solanzo FG & Guarano Al (1991): Energy expenditure and dietary intake of one to nineteen years old children. Philippine J. Sci. 120, 81-105.

Hackett AF, Rugg Gunn AJ, Appleton DR, Eastoe JE & Jenkins GN (1984): A 2-year longitudinal nutritional survey of 405 North-umberland children initially aged 11.5 years. Br. J. Nutr. 51, 67-75.

Hagman U. Bruce A, Persson LA, Samuelon G & Sjolin S (1986): Food habits and nutrients intake in childhood in relation to health and socioeconomic conditions. A Swedish multicentre study 19801981. Acta Paediatr. Scand., Suppl. 328, 1-56.

Hart J (1988): Patterns of household labour allocation in a Javanese Village. In Rural household studies in Asia, eds Hans Binswanger et al. Kent Ridge Singapore: Singapore University Press.

Henry CJK & Rees DG (1988): Basal metabolic rate and race. In Comparative nutrition, eds Blaxter K & Macdonald 1, pp 149-156. London: John Libbey.

Hitchcock NE, Owles EN, Gracey M & Gilmour M & Gilmour A (1984): Nutrition of healthy children in the second and third years of life. J. Fd. Nutr. 41, 13-16.

Ho Z-C, Zi HM, Bo L & Ping H (1988): Energy expenditure of preschool children in a subtropical area. Wrld Rev. Nutr. Diet. 57, 75-94.

Hoffmans MDA, Obermann-DeBoer GL, Florack KIM, van Kampen-Donker M & Kromhourt D (1986): Energy, nutrient and food intake during infancy and early childhood. The Leiden Preschool Children Study. Hum. Nutr. Appl. Nutr. 40A, 421-430.

Huenemann RL, Shapiro RL, Hampton MC & Mitchell BW (1967): Teen-agers' activities and attitudes toward activity. J. Am. Diet. Assoc. 51, 433440.

Ikemoto S. Sakamoto S. Venishi K, Wang M-F, Inoue G. Niiyama Y. Kishi K, Tanimoto H. Okada Y. Vezu N & Yamamoto S (1989): Actual energy and protein intakes and nitrogen balance in one year old Japanese children. Nutr. Rep. Intern. 39, 667-672.

Jenner DA, Vandongen R & Beilin LJ (1992): Relationships between blood pressure and measures of dietary energy intake, physical fitness and physical activity in Australian children aged 11-12 years. J. Epidemiol. Comm. Health 46, 108-113.

Jenner DA, English DR, Vandongen R. Beili LJ, Armstrong BK, Miller MR & Dunbar D (1988): Diet and blood pressure in 9-year-old Australian children. Am. J. Clin. Nutr. 47,1052-1059.
Johnson ML, Burke BS & Mayer J (1956): Relative importance of inactivity and overeating in the energy balance of obese high school girls. Am. J. Clin. Nutr. 4, 37-44.

Johnson A & Johnson O (1987): Time allocation among the Machiguenga of Shimaa. Cross-cultural studies in time allocation, volume 1. New Haven: Human Relations Area Files Press.

Johnson WA & Jensen JR (1984): Influence of noon meal on nutrient intakes and meal patterns of selected fifth-grade children. J. Am. Diet. Assoc. 84, 919-923.

Kaufmann NA, Friedlander Y, Halfon S-T, Slater PE, Dennis BH, McClish D, Eisenberg S & Stein Y (1982): Nutrient intake in Jerusalem: consumption in 17-year-olds. Israel J. Med. Sci. 18, 11671182.

Knuiman JT, Westenbrink S, Heyden L, West CE, Burema J, DeBoer J, Hautvast JGA, Räsänen L, Vikkunen L, Vükari J, Lokko P, Pobee JOM, Ferro-Luzzi A, Ferrini AM, Scaccini C, Sette S, Villa-vieja GM & Jayme-Bulatao J (1983): Determinants of total and high density lipoprotein cholesterol in boys from Finland, the Netherlands, Italy, the Philippines and Ghana with special reference to diet. Hum. Nutr. Clin. Nutr. 37C, 237254.

Lawrence M, Lawrence F, Durnin JVGA & Whitehead RG (1991): A comparison of physical activity in Gambian and UK children aged 6-18 months. Eur. J. Clin. Nutr. 45, 243-252.

Leung M, Yeung DL, Pennell MD & Hall J (1984): Dietary intakes of preschoolers. J. Am. Diet. Assoc. 84, 551-554.

Livingstone MBE, Coward WA, Prentice AM, Davies PSW, Strain JJ, McKenna PG, Mahoney CA, White JA, Stewart CM & Kerr MJJ (1992a): Daily energy expenditure in free-living children: comparison of heart-rate monitoring with the doubly labeled water (2H2 18O) method. Am. J. Clin. Nutr. 56, 343-352.

Livingstone MBE, Prentice AM, Coward WA, Strain JJ, Black AK, Davies, PSW, Stewart CM, McKenna PG & Whitehead RG (1992b): Validation of estimates of energy intake by weighed dietary record and diet history in children and adolescents. Am. J. Clin. Nutr. 56, 29-35.

Livingstone MBE, Prentice AM, Coward WA, Ceesay SM, Strain JJ, McKenna PG, Nevin GB, Barker ME & Hickey RJ (1990a): Simultaneous measurements of free-living energy expenditure by the doubly labeled water method and heart-rate monitoring. Am. J. Clin. Nutr. 52, 59-65.

Livingstone MBE, Prentice AM, Strain JJ, Black AK, Barker ME, McKenna PG & Whitehead RG (1990b): Accuracy of weighed dietary records in studies of diet and health. Br. Med. J. 300, 708712.

López-Jaramillo P, López de Garcia A, Prevot C, Félix C, Sosa C, Romero R, Grijalva Y & Rappaport R (1992): Effect of social class and nutrient intake on height and plasma insulin-like growth factor in Andean Ecuadorian children. Eur. J. Clin. Nutr. 46, 137-142.

Loucky J (1988): Children's work and family survival in highland Guatemala. Unpublished Ph.D. dissertation, University of California at Los Angeles (UCLA).

MacConnie SE, Gilliam TB, Geenen DL & Pels AE (1982): Daily physical activity patterns of prepubertal children involved in a vigorous exercise program. Int. J. Sports Med. 3, 202-207.

Magarey A & Boulton TJC (1984): Nutritional studies during childhood IV: Energy and nutrient intake at age 4. Aust. Paediatr. J. 20, 187 194.

Martinez OB (1982): Growth and dietary quality of young French Canadian school children. J. Can. Diet. Assoc. 43, 28-35.

McCoy H, Kenney MA, Kirby A, Disney G, Ercanli FG, Glover E, Korslund M, Lewis H, Liebman M, Livant E, Moak S, Stallings SF, Wakefield T, Schilling P & Ritchey SJ (1984): Nutrient intakes of female adolescents from eight southern states. J. Am. Diet. Assoc. 84, 1453-1459.

McKillop FM & Durnin JVGA (1982): The energy and nutrient intake of a random sample (305) of infants. Hum. Nutr. Appl. Nutr. 36A, 405-421.

McNaughton JW & Cahn AJ (1970b): A study of the energy expenditure and food intake of five boys and four girls. Br. J. Nutr. 24, 345-355.

McNaughton JW & Cahn AJ (1970a): A study of the food intake and activity of a group or urban adolescents. Br. J. Nutr. 24, 331-344.

Michaud C, Corniglion JM, Michel F, Musse N, Nicolas JP & Mejean L (1991): Sources of macronutrients and energy in the diet of a group of French high school students on school-days. J. Hum. Nutr. Diet. 4, 9199.

Min Q & Ho Z-C (1991): The basal metabolism rate of adolescent girls in the sub-tropical areas of China. Acta Nutrimenta Sinica 13, 252-258.

Morgan KG & Zabik ME (1981): Amount and food sources of total sugar intake by children ages 5-12 years. Am. J. Clin. Nutr. 34, 404-413.

Morrison JA, Larsen R, Glatfetter L, Bogg D, Burton K, Smith C, Kelly K, Mellies MJ, Khoury P & Glueck CJ (1980): Nutrient intake: relationships with lipids and lipoproteins in 6-19-year old children: the Princeton School District Study. Metabolism 29, 133140.

Mueller E (1984): The value and allocation of time in rural Botswana. J. Dev. Econ. 15, 329-360.

Munroe RL & Munroe RH (1989): Logoli time allocation. Cross-cultural studies in time allocation, volume 5. New Haven: Human Relations Area Files Press.

Munroe RH, Koel A, Munroe RL, Bolton R. Michelson C & Bolton C (1983): Time allocation in four societies. Ethnology 22, 355-370.

Nag M, White B & Peet RC (1978): An anthropological approach to the study of the economic value of children in Java and Nepal. Current Anthropology 19 (2), 293-306.

Narasinga Rao BS, Susheela TP, Nadamuni N & Menon K (1983): Energy intake of well-to-do preschool children in India. Indian J. Med. Res. 77, 62-72.

Neiderud J. Philip I & Sjolin A (1992)': Greek immigrant children in southern Sweden in comparison with Greek and Swedish children 111: energy and nutrient intake. Acta Paediatr 81, 430-435.

Nelson, M, Naismith DJ, Burley V, Gatenby S & Geddes N (1990): Nutrient intakes, vitamin-mineral supplementation and intelligence in British schoolchildren. Br. J. Nutr. 64, 13-22.

Niemi I, Kiiski S & Liikkanen M (1981): Use of time in Finland. Helsinki: Central Statistical Office of Finland.

Oliveira SA, Curtis Ellison R. Moore LL, Gillman MW, Garrahie EJ & Singer MR (1992): Parent-child relationships in nutrient intake: the Framingham Children's Study. Am. J. Clin. Nutr. 56, 593-598.

Palti H. Reshef A & Adler B (1979): Food intake and growth of children between 30 and 48 months of age in Jerusalem. Paediatrics 63, 713-718.

Pao EM, Mickle SJ & Burk MC (1985): One-day and 3-day nutrient intakes by individuals: Nationwide Food Consumption Survey findings, Spring 1977. J. Am. Diet. Assoc. 85, 313-324.

Paolisso M & Sackett R (1988): Time allocation among the Irapa-Yukpa. Cross-cultural studies in time allocation, volume 2. New Haven: Human Relations Area Files Press.

Parizkova J. Mackova E, Mackova J & Skopkova M (1986): Blood lipids as related to food intake, body composition, and cardiorespiratory efficiency in pre-school children. J. Pediatr. Gastroenterol. Nutr. 5, 295298.

Paul AA, Whitehead RG & Black AE (1990): Energy intakes and growth from two months to three years in initially breast-fed children. J. Hum. Nutr. Diet. 3, 79-92.

Payne JA & Belton NR (1992): Nutrient intake and growth in preschool children 1: comparison of energy intake and sources of energy with growth. J. Hum. Nutr. Diet. 5, 287-298.

Persson LA & Carlgren G (1984): Measuring children's diets: evaluation of dietary assessment techniques in infancy and childhood. Int. J. Epidemiol. 13, 506-517.

Pérusse L, Bouchard C, Leblanc C & Tremblay A (1984): Energy intake and physical fitness in children and. adults of both sexes. Nutr. Res. 4, 363370.

Post GB, Kemper HCG & van Essen LS' (1987): Longitudinal changes in nutritional habits of teenagers: differences in intake between schooldays and weekend days. Br. J. Nutr. 57, 161-167.

Prentice AM, Lucas A, Vasquez-Velasquez L, Davies PSW & Whitehead RG (1988): Are current dietary guidelines for young children a prescription for overfeeding? Lancet 2, 1066-1068.

Prentice AM, Black AK, Coward WA, Davies HL, Goldberg GR, Ashford J. Sawyer M & Whitehead RG (1986): High levels of energy expenditure in obese women. Br. Med. J. 292, 983-987.

Ramirez M & Torun B (1994): Actividad fisica y necesidades de energia de escolares con distintos antecedentes nutricionales. Presented at 36th Congress of Pediatrics, Guatemala.

Räsänen L, Laitinen S. Stirkkinen R. Kimppa S. Vükari J. Uhari M Pesonen E, Salo M & Akerblom HK (1991): Composition of the diet of young Finns in 1986. Ann. Med. 23, 73-80.

Räsänen L & Ylonen K (1992): Food consumption and nutrient intake of one- to two-year old Finnish children. Acta Paediatr. 81, 7-11.

Räsänen L, Ahola M, Kara R & Uhari M (1985): Atherosclerosis precursors in Finnish children and adolescents VIII: food consumption and nutrient intakes. Acta Paediatr. Scand., Suppl. 318, 135-153.

Rodgers G & Standing G (Eds) (1981): Child work, poverty and under development. Geneva: International Labour Office.

Rodriguez MM (1991): Evaluación dietética de grupos de escolares de diferentes esteblecimientos educativos mediante la aplicación de dos métodos de consumo de alimentos. Unpublished B.S. thesis, Facultad de Ciencias Químicas y Farmacia, Universidad de San Carlos de Guatemala.

Rueda-Williamson R. Luna-Jaspe H. Ariza J. Pardo F & Mora JO (1969): Estudio seccional de crecimiento, desarrollo y nutrición en 12,138 niños de Bogotá, Colombia. Pediatria (Colombia) 110, 337349

Rutenfranz J, Berndt I & Knauth P (1974): Daily physical activity investigated by time budget studies and physical performance capacity of school boys. Acta Paediatr. Belg. 28, Suppl., 79-86.

Salas J, Galan P, Arija V, Marti-Henneberg C & Hercberg S (1990): Iron status and food intakes in a representative sample of children and adolescents living in a Mediterranean city of Spain. Nutr. Res. 10, 379390.

Salz KM, Tamir 1, Ernst N, Kwiterovich P, Glueck C, Christensen B, Larsen R, Pirhonen D, Prewitt TE & Scott LW (1983): Selected nutrient intakes of free-living white children ages 6-19 years. The Lipid Research Clinics Program Prevalence Study. Paediatr. Res. 17, 124-130.

Saris WHM, Emons HJG, Groenenboom DC & Westerterp KR (1989): Discrepancy between FAO/WHO energy requirements and actual energy expenditure in healthy 7-11 year old children. Abstracts 14 International Seminar on Pediatr Work Physiol, Lueven, Belgium.

Saris WHM, Binkhorst RA, Cramwinckel AB, Van Der Veen-Hezemans AM & Van Waesderghe F (1979): Evaluation of somatic effects of a health education program for schoolchildren. Bibl. Nutr. Dieta 27, 77-84.

Sawaya WN, Tannous Rl, Othaimeen Al (1988): Dietary intake of Saudi infants and preschool children. Ecol. Fd. Nutr. 20,171-184.

Schoeller DA (1990): How accurate is self-reported dietary energy intake? Nutr. Rev. 48, 373-379.

Schofield WN (1985): Predicting basal metabolic rate, new standards and review of previous work. Hum. Nutr. Clin. Nutr. 39C, Suppl. 1, 5-41

Schürch B & Scrimshaw NS (1990): Activity, energy expenditure and energy requirements of infants and children. Lausanne: International Dietary Energy Consultancy Group.

Seliger V, Trefny Z, Bartunkova S & Pauer M (1974): The habitual activity and physical fitness of twelve year-old boys. Acta Paediatr. Belg. 28, 5459.

Seone NA & Roberge AG (1983): Caloric and nutrient intake of adolescents in the Quebec City Region. Can. J. Public Health 74, 110116.

Shephard RJ, Jéquier JC, Lavallée H, La Barre R & Rajic M (1980): Habitual physical activity: effects of sex, milieu, season and required activity. J. Sports Med. 20, 55-66.

Simons-Morton BG, Parcel GS, O'Hara HM, Blair SN & Pate RR (1988): Health-related physical fitness in childhood. Ann. Rev. Public Health 9, 403-425.

Skinner JD, Salvetti NN, Ezell JM, Penfield MP & Costello CA (1985): Appalachian adolescents' eating patterns and nutrient intakes. J. Am. Diet. Assoc. 85,1093-1099.

Spady DW (1980): Total daily energy expenditure of healthy, free ranging school children. Am. J. Clin. Nutr. 33, 766-775.

Spurr GB, Prentice AM, Murgatroyd PR, Goldberg GR, Reina JC & Christman NT (1988): Energy expenditure from minute-by-minute heart-rate recording: a comparison with indirect calorimetry. Am. J. Clin. Nutr. 48, 552-559.

Spurr GB & Reina JC (1987): Marginal malnutrition in school-aged Colombian girls: dietary intervention and daily energy expenditure. Hum. Nutr. Clin. Nutr. 41C, 93-104.

Spurr GB & Reina JC (1988a): Patterns of daily energy expenditure in normal and marginally undernourished school-aged Colombian children. Eur. J. Clin. Nutr. 42, 819-834.

Spurr GB & Reina JC (1988b): Influence of dietary intervention on artificially increased activity in marginally undernourished Colombian boys. Eur. J. Clin. Nutr. 42, 835-846.

Spurr GB & Reina JC (1989a): Energy expenditure basal metabolic rate ratios in normal and marginally undernourished Colombian children 6-16 years of age. Eur. J. Clin. Nutr. 43, 515-527.

Spurr GB & Reina JC (1989b): Maximum oxygen consumption in marginally malnourished Colombian boys and girls 6-16 years of age. Am. J. Hum. Biol. 1, 11-19.

Spurr GB, Reina JC & Barac-Nieto M (1986): Marginal malnutrition in school-aged Colombian boys: metabolic rate and estimated daily energy expenditure. Am. J. Clin. Nutr. 44, 113-126.

Spurr GB, Reina JC & Hoffmann RG (1992): Basal metabolic rate of Colombian children 2-16 years of age: ethnicity and nutritional status. Am. J. Clin. Nutr. 56, 623-629.

Stefanik P, Heald, Jr, FP & Mayer J (1959): Caloric intake in relation to energy output of obese and non-obese adolescent boys. Am. J. Clin. Nutr. 7, 55-62.

Story M (1986): Anthropometric measurements and dietary intakes of Cherokee indian teenagers in North Carolina. J. Am. Diet. Assoc. 86, 1555-1560.

Strain JJ, Robson PJ, Livingstone MBE, Primrose ED, Savage JM, Cran GW & Boreham CAG (1994): Estimates of food and macro nutrient intake in a random sample of Northern Ireland adolescents. Br. J. Nutr. 72, 343-352.

Sunnegardh J. Bratteby LE, Hagman U. Samuelson G & Sjolin S (1986): Physical activity in relation to energy intake and body fat in 8- and 13-year-old children in Sweden. Acta Paediatr. Scand. 75, 955-963.

Sunnegardh J. Bratteby LE & Sjolin S (1985): Physical activity and sport involvement in 8-13 year old children in Sweden. Acta Paediatr. Scand. 74, 904-912.

Tan SP, Wells JE, Beaven DW & Hornblow AR (1989): Energy and macronutrient intake of New Zealand adolescents. Ecol. Food Nutr. 23, 225-236.

Tayter M, Stanek KL (1989): Anthropometric and dietary assessment of omnivore and lacto-ovo-vegetarian children. J. Am. Diet. Assoc. 89, 16611663.

Torun B & Viteri FE (1981b): Energy requirements of preschool children and effects of varying energy intakes on protein metabolism. Food Nutr. Bull., Suppl. 5, 229-241.

Torun B & Viteri FE (1981a): Capacity of habitual Guatemalan diets to satisfy protein requirements of preschool children with adequate dietary energy intakes. Food Nutr. Bull., Suppl. 5, 210-228.

Torun B. Rodriguez M, Ramirez M & Viteri FE (1993): Energy expenditure and intake of pubertal girls of low-income families in Guatemala. Presented at 15th International Congress of Nutrition, Adelaide, Australia.

Torun B (1984): Physiological measurements of physical activity among children under free living conditions. In: Energy intake and activity, eds E Pollit & P Amante, pp 159-184. New York: Alan R Liss.

Torun B (1983): Inaccuracy of applying expenditure rates of adults to children. Am. J. Clin. Nutr. 38, 813-814.

Torun B (1990a): Energy cost of various physical activities in healthy children. In: Activity, energy expenditure and energy requirements of infants and children, eds Schürch B & Scrimshaw NS, pp 139-183. Lausanne: International Dietary Energy Consultancy Group.

Torun B (1990b): Short- and long-term effects of low or restricted energy intakes on the activity of infants and children. In: Activity, energy expenditure and energy requirements of infants and children, eds Schürch B & Scrimshaw NS, pp. 335-358. Lausanne: International Dietary Energy Consultancy Group.

Treiber FA, Leonard SB, Frank G. Musante L, Davis H. Strong WB, Levy M (1990): Dietary assessment instruments for preschool children: reliability of parental responses to the 24-hour recall and food frequency questionnaire. J. Am. Diet. Assoc. 90, 814-820.

Turke P (1988): Helpers at the nest: childcare networks of Ifaluk. In Human reproductive behavior, eds Betzig L, Borgerhoff Mulder M & Turke P. pp. 173-188. Cambridge: Cambridge University Press.

van den Reek MM, Craig-Schmidt MC, Weete JD & Clark AJ (1986): Fat in the diets of adolescent girls with emphasis on isomeric fatty acids. Am. J. Clin. Nutr. 43, 530-537.

Van Steenbergen WM, (1984): Food consumption of different household members in Machakos, Kenya. Ecol Fd. Nutr. 14, 1-9.

Vanderkooy PDS & Gibson R (1987): Food consumption patterns of Canadian pre-school children in relation to zinc and growth status. Am. J. Clin. Nutr. 45, 609-616.

Verschurr R & Kemper HCG (1985): Habitual physical activity. Med. Sport. Sci. 20, 56-65.

Walker SP, Powell CA, Grantham-McGregor SM (1990): Dietary intakes and activity levels of stunted and non-stunted children in Kingston, Jamaica. Part 1. Dietary intakes. Eur. J. Clin. Nutr. 44, 527-534.

Weir JB (1949): New methods for calculating metabolic rate with special reference to protein metabolism. J. Physiol. 109, 1-9.

Wong WW (1994): Energy expenditure of female adolescents. J. Am. Coll. Nutr. 13, 332-337

Woodward D (1984): Major influences on median energy and nutrient intakes among teenagers: a Tasmanian study. Br. J. Nutr. 52, 21-32.

Discussion

Initially, the discussion dealt with the selection of studies and data that form the basis of the paper and recommendations of Torun et al. For methodological reasons, Ferro-Luzzi questioned the validity of older energy expenditure data based on heart rate measurements. She also argued that the life-styles of children are changing so rapidly, also in developing countries, that time allocation studies made more than 10 years ago may no longer reflect today's situation. Torun explained and justified the selection criteria that were used in greater detail and argued that, in general, there was a reasonably good fit between data obtained by different methods at different points in time. Shetty supported this view and emphasized the relatively good fit even with data that were collected in the 1970s and formed the basis of the 1985 report.

There was general agreement that energy requirements should be based on data on energy expenditures of normal children. Some of the data in the paper of Torun et al were from children from developing countries who were of low height-for-age (stunted), but otherwise 'normal', healthy, and adequately nourished (in terms of BMI and weight-for-height) at the time the measurements were taken. There was some debate as to whether data of such children should be included in the data base or not, particularly since energy expenditures of stunted children, expressed per kg body weight, are higher than those of non-stunted children of the same weight. In the end, the prevailing view was that in making recommendations one could not ignore that large proportions of children in developing countries are stunted, but otherwise healthy and normal, and that it seems therefore justified to include such data (Town, Scrimshaw). Another argument was that recommending the feeding of stunted but otherwise healthy children additional energy to catch up in height (i.e. by determining their dietary energy requirements on the basis of ideal rather than actual weight, as one does with protein) will only tend to make them obese (Scrimshaw, Torun), and as long as dietary recommendations to satisfy energy requirements are made by age groups in absolute terms (i.e. energy units per day) and not by kg body weight or lean body mass, there will be no substantial difference between stunted and non-stunted children.

Several discussants speculated on the reasons why energy expenditures per kg body mass or LBM tend to be higher in stunted children than in children of normal height. Behavioral and life-style differences could be responsible for some of the differences found in DLW studies. This argument is supported by heart-rate and time-motion studies tending to show that stunted children from lower socioeconomic classes are likely to have a different life-style. Using minute-by-minute records and estimating the time spent in various categories of activities. Torun found that poorer children spent less time in sedentary and more time in light activities. Spurr found no differences in activity between well nourished and marginally nourished Colombian children during the school year, but the better nourished children were more active in leisure activities during the summer holidays. Comparing heart rates of children from the UK and developing countries, Prentice found that UK children had higher heart rates.

Torun argued in his paper and in the discussion that, in general, studies show differences in life-style requiring more energy-demanding activities from children of rural populations in developing countries. To Schüch this conclusion appeared to be a reflection of the assumptions made rather than an inference from empirical data. Table 14 shows that it is assumed that children living in rural areas of developing countries spend a greater proportion of their time in domestic chores and production activities requiring greater effort. These assumption; are used to calculate mean daily EE in terms of PAL factors from which it is then concluded that energy expenditures are higher in rural than in urban and industrial environments. This argument seems to a large extent circular.

Body mass and LBM are both very heterogeneous, i.e. composed of different tissues with different energy requirements. If their proportions differ between children of low and normal height this could explain some of the differences observed in calorimetric studies (Young). The results of a few small studies that tried to test this hypothesis remain inconclusive, and more work is needed to clarify this issue. Differences in body proportions have been observed: stunted Peruvian children, for instance, tend to have reduced limb length relative to the size of their trunks (Reeds), and the secular trend in Japanese to become taller reflects primarily an increase in leg length (Butte).

Several participants (e.g. Ferro-Luzzi & Torun) emphasized how difficult it was to measure the energy cost of activities in children and argued for the development of instruments that are better adapted to children.

Much of the discussion dealt with the introduction of PAL indices and their values reflecting the different lifestyles of different groups of children. Torun integrated a section on this issue into the final version of his paper. He also defined cut-off points in terms of PAL values. Dietary intake data, for instance, lying below or above these cut-offs were considered physiologically improbable and excluded from the data base.

Some discussants expressed concern about the current trend towards increasingly sedentary life-styles not only in adults, but also among children. Should proposed PAL values reflect actual or desirable levels of activity? Butte and Durnin expressed doubts that we have enough information to be prescriptive; others feared that by recommending higher PAL values without being able to ensure that children actually do increase their level of physical activity may well lead to recommendations that are inappropriately high.

Hautvast commented on the dietary intakes presented in Figure 10, and showing that energy intakes appear to be higher than energy expenditures in infants and lower than energy expenditures in adolescents. This appears quite plausible considering that dietary intakes during the first years of life are mainly based on reports of caretakers, who are more likely to over-report intakes, whereas adolescents, trying to stay slim, may under-report intakes. Torun also finds this interpretation quite plausible, particularly because adolescent girls reported intakes that were further below predicted values than the intakes reported by adolescent boys. Torun added further that the discrepancy between intakes and expenditures tends to be greater in data from the US (Dietz) than from the UK (Livings/one). Prentice emphasized that only a few of the columns in Figure 10 exceed the range representing the estimated limits of precision, given the inaccuracies of both methods.

Waterlow raised the question of how accurate recommendations needed to be. The answer obviously depends on the use to which recommendations are to be put. To assess the adequacy of food available to countries or populations, FAO and other organizations use food balance sheets and estimates of population structure and food wastage which are notoriously inaccurate; in this context it appears unnecessary to try to formulate recommendations with an accuracy below 5 kcal/kg. Of greater concern are cumulative effects of errors. Reed pointed out that the energy equivalent of an excess of 5 kcal/kg/d for a year in a 14 year old weighing 40 kg amounts to about 8 kg. Clugston mentioned that WHO is often approached by governments and agencies who use these recommendations to calculate energy requirements of populations. Since children are often 40% of the population of poor countries, the accuracy of requirements is quite important for such calculations. Since a large proportion of children in poor countries are undernourished, Clugston encouraged IDECG to examine further the energy (and other dietary) requirements of stunted and wasted children.