Cover Image
close this book4th Report on the World Nutrition Situation - Nutrition throughout the Life Cycle (ACC/SCN, 2000, 138 p.)
close this folderCHAPTER 3: BREASTFEEDING AND COMPLEMENTARY FEEDING
View the document(introduction...)
View the document3.1 Evidence Linking Breastfeeding to Improved Outcomes
View the document3.2 Evidence Linking Complementary Feeding to Improved Outcomes
View the document3.3 Conceptualizing Infant Feeding Behaviours
View the document3.4 HIV and Infant Feeding
View the document3.5 Breastfeeding and Complementary Feeding Patterns and Trends
View the document3.6 Role of National and International Initiatives in Support of Optimal Infant Feeding
View the document3.7 Looking Forward: The Importance of Exclusive Breastfeeding

(introduction...)

Breastfeeding and complementary feeding behaviours are important predictors of infant and child nutrition, health, and survival. The vast majority of research has focused on the benefits of breastfeeding and complementary feeding to infants and young children, although there are also important benefits throughout the life cycle. There is evidence to link having been breast-fed as a child with stronger intellectual development1-3 and a reduced risk of cancer,4 obesity,5 and several chronic diseases.6, 7 Breastfeeding also benefits maternal health. Women who breastfeed have a reduced risk of ovarian cancer and premenopausal breast cancer.8-10 Women who were breastfed as infants also have a reduced risk of breast cancer.11

Improving breastfeeding and complementary feeding practices will therefore improve health, nutrition, and survival in the short - as well as the long - term and contribute to the well being of future generations. Because of the increasing recognition of the importance of foetal and early childhood nutrition throughout the life cycle, data on breast-feeding and complementary feeding are included for the first time in an ACC/SCN report on the world nutrition situation.

3.1 Evidence Linking Breastfeeding to Improved Outcomes

Breastfeeding contributes to infant nutrition and health through a number of important mechanisms. It provides a complete source, of nutrition for the first six months of life, half of all requirements in the second six months of life, and one-third of requirements in the second year of life.12 It provides immunity as well as other factors that protect against specific illnesses. When infants and children become ill, breastfeeding provides an important source of nutrients because intake of breastmilk is not reduced in contrast to the intake of complementary foods, which declines considerably.13-15 Furthermore, exclusive breastfeedinga eliminates the risk of illness through the use of contaminated foodstuffs and utensils. It also lengthens the period of postpartum amenorrhoea and hence, in the absence of contraceptive use, lengthens the birth interval, which is strongly related to infant and child survival.

a Breastfeeding with no other food or fluid given to the child, not even water.

Because infant feeding mode cannot be randomly assigned, all data on the protective effect of breastfeeding on morbidity and mortality are observational. However, the dose-response effect observed with exclusive breastfeeding, any breastfeeding, and no breastfeeding provides evidence of causality.16-19 The risk of death decreases dramatically as the infant ages; therefore the protective effect of breastfeeding on mortality is greatest in the first month of life and declines by month until 6 months.20 Many - though not all - studies continue to show protective effects until 12 months of life, and some studies show protective effects into the second year as well. A dose response has also been observed between the amount of breastmilk consumed through a naso gastric tube in preterm infants and cognitive development1 and between a longer duration of exclusive breastfeeding and reduced risk of obesity among school-age children.5 A similar pattern is observed with the protective effect of breastfeeding on morbidity, with the protective effects being greatest in the first 6 months of life and reduced thereafter.17, 18

3.2 Evidence Linking Complementary Feeding to Improved Outcomes

It is difficult to meet the zinc and iron requirements of children 6 to 24 months even in the best conditions.12 Inadequate micronutrient and energy intake is often coupled with a high prevalence of both clinical and subclinical morbidity, which is often associated with anorexia. This is the period of active growth faltering. Interventions to improve intake of complementary foods can result in improved infant and child growth among populations at risk of undernutrition. A review of efficacy trials and programmes in 14 countries showed that child growth could be improved by 0.10 to 0.50 standard deviation (SD) through increased dietary intakes. This range of improvement in growth would reduce prevalences of undernutrition (< - 2 SD) at 12 months by 1-19%.21 The effects of improved nutritional intake on growth are greatest in the first year of life, though significant effects continue into the second and third year.22, 23 Nutritional status during the first two years of life, which coincides with the period of peak diarrhoeal disease and high prevalences of respiratory infections, is particularly important in light of the fact that adequate nutrition mitigates the negative effect of diarrhoea on linear growth.24

In Central and South America and the Caribbean there is renewed interest in the role that processed complementary foods can play in providing a nutritionally complete infant and toddler food.25 Processed complementary foods, appropriately fortified, can complement breastmilk and traditional foods during the nutritionally vulnerable period. Because these foods can be produced inexpensively and require minimal rime for preparation and cooking, they alleviate other economic and time-related constraints to improved child feeding. Risk of food contamination may also be reduced through good packaging. Despite these advantages, processed complementary foods have not been shown to be effective outside the research setting at improving the nutritional status of children at risk of undernutrition. Sustainability is also an issue. Inadequate attention has been given to cultural acceptabability, as well as cost and financing, social marketing, targetting, and distribution. Processed complementary foods often fail to reach the poorest households, and when they do, breastfeeding practices and other key feeding behaviours have not been improved simultaneously.

3.3 Conceptualizing Infant Feeding Behaviours

The full impact of optimal breastfeeding and complementary feeding, as measured by population level reductions in mortality and morbidity and improved health and development, will never be realized unless women and caregivers adopt recommended behaviours. Recommended behaviours change as an infant and young child grows.12 WHO defines optimal behaviours as exclusive breastfeeding for four to six months, breastfeeding with complementary feeding starring at about six months of age, and continued breastfeeding in the second year of life and beyond.26 Field studies show that complementary foods introduced between four and six months of age replace nutrients from breastmilk and confer no advantage on growth or development.27, 28 As a result UNICEF and many ministries of health in general recommend exclusive breastfeeding for about six months. Having two sets of recommendations creates confusion, and policy harmonization is urgently needed in this area.

Whether or not optimal behaviours are adopted is a result of the interaction of many factors. The closest determinants relate to a woman’s choice and her ability to act upon this choice. For optimal breastfeeding and complementary behaviours to occur, a woman must both wish to use them and be able to choose them. The two factors are influenced most immediately by the infant feeding information a woman receives as well as the physical and social support provided to her during pregnancy, childbirth, and postpartum. These factors are, in turn, influenced by familial, medical, and cultural attitudes and norms, demographic and economic conditions (including the resources to grow or purchase needed foods and maternal employment), commercial pressures, and national and international policies and norms. Thus, to promote optimal breastfeeding and complementary feeding behaviours, interventions need to be targeted not only to individual women but also to changing the context in which infant and child feeding choices are made.

The determinants of infant feeding behaviours are shown in Figure 3.1. This figure elaborates the interplay between factors that determines the capacity, resources, and care practices for young children.


FIGURE 3.1: Determinants of infant feeding behaviours

Source: 29.

3.4 HIV and Infant Feeding

The finding that HIV is transmitted through breast-milk has complicated infant feeding recommendations.30 Recognizing breastfeeding as a significant and preventable mode of HIV transmission, the Joint United Nations Programme on HIV/AIDS (UNAIDS), together with WHO and UNICEF, issued new guidelines on HIV and infant feeding in 1998.31 These guidelines call for urgent action to educate, counsel, and support HIV-positive women in making decisions about how to nourish their infants safely. The guidelines stress that in order for a mother to make a decision, she must have access to voluntary and confidential testing and counselling, as well as to information about feeding options and the risks associated with them.

Since these guidelines were published, observational data have shown that three-month-old infants of HIV-positive women who were exclusively breast-fed have the same risk of contracting HIV as infants who were never breastfed. In contrast, infants who were partially breastfed had a significantly higher risk.32 Several biological mechanisms could explain why exclusive breastfeeding might be more protective than partial breastfeeding. These include the mother’s reduced risk of subclinical mastitis, which occurs during breast engorgement,33 and increased integrity of the infant’s intestinal wall. Research is under way to confirm if these important findings are causal.

Shortened duration of breastfeeding is one infant feeding option suggested in the new UNAIDS/WHO/UNICEF guidelines. Confirmation of the protective effect of exclusive breastfeeding on the risk of mother-to-child transmission of HIV is a necessary first step in developing a policy recommendation that would give infants the benefits of exclusive breastfeeding while avoiding the risk of HIV transmission through partial breastfeeding.

3.5 Breastfeeding and Complementary Feeding Patterns and Trends

This section uses data from nationally representative household demographic and health surveys to provide trend information on breastfeeding, complementary feeding, and bottle feeding. Data are presented from national surveys conducted with technical support from the Demographic and Health Surveys (DHS). Current status data are used to determine infant feeding patterns to avoid problems associated with recall bias. Surveys from 1990 to 1996 reporting on current infant and childhood feeding patterns are available for 37 countries. Twenty-seven countries supported by DHS or World Fertility Surveys have multiple surveys that permit analysis of trends of breastfeeding initiation and of the median duration of breastfeeding covering the period 1975 to 1996. These data were published in June 1999 by Macro International in a report titled Breastfeeding and Complementary Feeding, and the Postpartum Effects of Breastfeeding.34 In addition, analysis of DHS data for Latin America and the Caribbean by the Pan American Health Organization permits presentation of trends in exclusive breastfeeding for the years 1986 to 1996.35

This review shows that breastfeeding initiation rates are very high in developing countries. The incidence of breastfeeding initiation exceeds 90% in almost every country and exceeds 95% in more than half of the countries. Breastfeeding initiation is universal in Sub-Saharan Africa. However, breastfeeding practices are far from optimal. The recommendation for exclusive breastfeeding is not widely practiced (Table 3.1). In general, the proportion of infants under four months of age who are exclusively breastfed is highest on average in Asia (up to 82% in Nepal) and the Near East/North Africa (63% in Morocco) followed by Latin America and Sub-Saharan Africa. There is significant variation within regions. For example, in Latin America and the Caribbean, the proportion of infants under four months of age who are exclusively breastfed ranges from less than 5% in Haiti to more than 50% in Bolivia, Guatemala, and Peru.

WHO and others recommend that all infants six to nine months of age be breastfed and also receive complementary foods. Data on “breastfeeding plus complementary foods” shown in Table 3.1 reflect the timing of introduction of complementary foods but provide no information about the quality of these foods. Again there is large variation within regions. For example, in Sub-Saharan Africa one-third of infants in Ghana and Mali are receiving complementary foods, compared with 90% or more in Kenya and Zimbabwe. In general, low prevalences for this indicator in Latin America and the Caribbean are because infants are no longer being breastfed rather than because they are not receiving complementary foods. Delayed introduction of complementary foods is a serious problem in some countries. Less than one-third of infants receive complementary foods by six to nine months in Bangladesh, India, and Pakistan, according to surveys conducted in the early 1990s.

TABLE 3.1: Breastfeeding and complementary feeding practices

Region, country, and date

Exclusive breastfeeding, < 4 months (%)

Breastfeeding plus complementary foods, 6-9 months (%)

Breastfeeding, 12-15 months (%)

Breastfeeding, 20-23 months (%)

Bottle feeding, <4 months (%)

Sub-Saharan Africa


Burkina Faso 1993

3.1

43.9

98.0

81.7

1.6


Cameroon 1991

7.3

77.1

80.7

37,8

17.8


Central African Republic 1994-95

4.4

93.1

96.6

54.8

2.3


Cd’Ivoire 1994

3.4

66.2

94.9

47.5

4.5


Ghana 1993

8.3

35.7

94.6

55.4

23.9


Kenya 1993

17,0

90.1

91.3

57.6

16.4


Madagascar 1992

48.4

80.0

91.1

51.7

3.7


Malawi 1992

3.3

87.2

94.5

59.9

3.8


Mali 1995

12.2

32.9

94.3

62.8

2.9


Namibia 1992

21.6

64.7

69.1

24.8

31.1


Niger 1992

1.3

73.2

96.3

63.7

2.1


Nigeria 1990

1.4

51.7

86.9

46.3

33.6


Rwanda 1992

90.2

67.8

98.6

89.0

0.7


Senegal 1992-93

6.5

58.9

94.1

50.6

6.2


Tanzania 1991-92

32.5

58.7

94.7

59.5

4.1


Uganda 1995

70.4

63.6

88.5

45.0

5.6


Zambia 1992

13.3

87.6

91.1

34.9

3.2


Zimbabwe 1994

16.3

93.0

89.8

26.7

5.8

Near East/North Africa


Egypt 1992

54.0

52.3

77.9

42.4

19.9


Jordan 1990

32.0

48.1

48.3

17.2

29.8


Morocco 1992

62.9

35.1

64.6

31.7

23.1


Turkey 1993

13.9

47.1

47.5

18.2

29.4

Asia


Bangladesh 1993-94

53.5

29.4

96.1

91.2

0.0


India 1992-93

51.2

31.5

89.0

73.0

9.2


Indonesia 1994

47.6

85.8

88.8

76.6

10.6


Kazakhstan 1995

12.3

62.7

52.3

24.1

69.0


Nepal 1996

82.0

62.5

96.7

92.7

2.3


Pakistan 1990-91

25.1

29.2

79.7

59.4

26.2


Philippines 1993

33.1

52.1

58.2

24.2

43.0

Latin America/Caribbean







Bolivia 1993-94

54.0

78.0

74.7

42.7

34.7


Brazil 1996

40.8

11.6

34.8

18.8

50.9


Colombia 1995

15.7

61.5

42.8

18.8

72.0


Dominican Republic 1991

9.6

22.8

29.5

9.1

80.8


Guatemala 1995

50.7

55.7

78.0

54.0

26.4


Haiti 1994

3.3

84.1

82.4

26.7

36.4


Paraguay 1990

7.0

61.2

40.3

11.1

56.1


Peru 1996

61.4

72.2

81.6

45.8

28.6

Source: Abstracted or calculated from information presented in 34.

The prevalence of breastfeeding between 12 and 15 months is relatively high in all regions. In Sub-Saharan Africa 13 of the 18 countries reported here have breastfeeding rates exceeding 90%. For other regions, again, there is significant variation. In Latin America and the Caribbean, breastfeeding at 12-15 months ranges from a low of 30% in the Dominican Republic and 35% in Brazil to about 80% in Guatemala, Haiti, and Peru. Prevalences of breastfeeding among children 20 - 23 months of age are highest in Sub-Saharan Africa and Asia (over 50%) and lowest in Latin America and the Caribbean and the Near East/North Africa (about 25%).

Bottle feeding carries a significant risk of morbidity because of contamination36 and is therefore a useful indicator to follow. Bottle feeding is highly variable, depending on the region and the country. In general, it is lowest in Sub-Saharan Africa, although one-third of infants are bottle fed in the first four months in Namibia and Nigeria. Bottle feeding rates are very high in Latin America and the Caribbean. In four of the eight countries reported on, more than half of infants less than four months are bottle fed. A very high rate of bottle feeding is reported for Kazakhstan in Central Asia (69%), whereas rates are much lower elsewhere in Asia - for example, 9.2% in India.

TABLE 3.2: Trends in the median duration of breastfeeding

Region, country, and date

Median duration (months)

Sub-Saharan Africa


Cameroon 1978

17.8


Cameroon 1991

18.2


Ghana 1979-80

17.8


Ghana 1988

21.5


Ghana 1993

21.6


Kenya 1977-78

16.6


Kenya 1989

20.0


Kenya 1993

21.6


Mali 1987

18.6


Mali 1995

22.5


Nigeria 1982

17.0


Nigeria 1990

19.8


Rwanda 1984

20.9


Rwanda 1992

28.0


Senegal 1978

18.0


Senegal 1986

18.9


Senegal 1992-93

20.2


Uganda 1988-89

19.5


Uganda 1995

19.3


Zimbabwe 1988-89

19.1


Zimbabwe 1994

18.1

Near East/North Africa


Egypt 1980

15.3


Egypt 1988-89

19.8


Egypt 1992

19.8


Jordan 1976

10.9


Jordan 1990-91

12.1


Morocco 1980

15.9


Morocco 1987

15.4


Morocco 1992

15.5


Turkey 1978

11.7


Turkey 1993

11.7

Asia


Bangladesh 1975-76

25.8


Bangladesh 1993-94

36.0


Indonesia 1976

23.3


Indonesia 1987

23.3


Indonesia 1991

23.6


Indonesia 1994

23.7


Nepal 1976

24.2


Nepal 1996

31.3


Pakistan 1975

17.8


Pakistan 1990-91

18.5


Philippines 1978

14.1


Philippines 1993

15.4

Latin America/Caribbean


Bolivia 1989

16.4


Bolivia 1993-94

17.5


Brazil 1986

5.8


Brazil 1996

7.8


Colombia 1976

7.9


Colombia 1986

9.1


Colombia 1990

9.3


Colombia 1995

10.3


Dominican Republic 1975

8.4


Dominican Republic 1986

8.1


Dominican Republic 1991

5.9


Guatemala 1.987

20.6


Guatemala 1995

20.2


Haiti 1977

15.6


Haiti 1994

17.7


Paraguay 1979

12.4


Paraguay 1990

11.7


Peru 1977-78

14.5


Peru 1986

14.1


Peru 1991-92

18.1


Peru 1996

20.2

Source: 34.

Overall, data on trends in the median duration of breastfeeding show positive changes between 1975 and 1996 (Table 3.2). The high median duration of breastfeeding was maintained in many countries and actually increased in some. Increases in the median duration of breastfeeding measured over a ten-year period range from about one month in the Near East/North Africa to 2.5 months in Sub-Saharan Africa. When all countries were considered together, the median duration of breastfeeding increased at a rate of 1.7 months per decade. Work is under way to extend the analysis of trends in breast-feeding and complementary feeding by developing comprehensive indicators of care. This work is described in Box 3.1.

BOX 3.1

Approaches to Measuring and Quantifying Care

Care is defined as “the behaviours and practices of caregivers (mothers, fathers, siblings, and child-care providers) to provide the food, health care, stimulation, and emotional support necessary for children’s healthy growth and development.”37 Over the past decade, care has been increasingly recognized as a crucial input into child health and nutrition, along with food security, availability of health services, and a healthy environment.

In 1995 a special issue of the Food and Nutrition Bulletin presented an extensive review of the literature on care and its determinants and provided recommendations for protecting and enhancing the quality of care. A useful distinction has also since been made between “care resources” and “care practices.” The latter includes the following six main areas of caregiving behaviours: (1) care for women; (2) feeding/breastfeeding; (3) psycho-social and cognitive stimulation; (4) hygiene practices; (5) home health practices; and (6) food preparation and storage. Indicators for measuring care were also identified.

In 1997 WHO, along with IFPRI and the University of Ghana, undertook a survey in Accra using the food-health-care conceptual model to examine the determinants of child undernutrition. One of the greatest challenges was to identify an approach to measuring and quantifying care. Data on child feeding practices and use of preventive health services were collected, and the information was used to create an age-specific child-care index. The index was particularly useful in examining the importance of care for child undernutrition and in studying the determinants of caring practices in this population. The main findings were (1) good care practices for children 4 - 36 months of age were beneficial for child nutritional status and could partially compensate for the negative effects of low maternal schooling and poverty; (2) the most important constraint to good child care practices was maternal schooling; and (3) household socioeconomic factors, food security, maternal work, and other maternal characteristics did not interfere with caring practices in this population.38, 39

In collaboration with Cornell University and Emory University, IFPRI is now using DHS data sets to pursue its work in measuring and quantifying care. The focus is on using the information available on breastfeeding and complementary feeding to derive a child feeding index for various countries and regions around the world. Preliminary work shows promising results, and the findings should help improve our understanding of the role of care in the etiology of childhood undernutrition in different settings. The research will also help identify minimum data needs and useful indicators for measuring and quantifying care. The current focus is on child feeding practices because of data availability, but research is urgently needed on indicators and methodologies to quantify other more complex aspects of care, such as psychosocial and cognitive stimulation or care of women, which remain largely understudied.

3.6 Role of National and International Initiatives in Support of Optimal Infant Feeding

Improvements in breastfeeding behaviours have occurred at the same time as demographic changes, such as increased urbanization and increases in hospitalization for childbirth, female education and employment, and use of modern contraceptives, which traditionally have been negatively associated with breastfeeding.40 The role of national and international initiatives in support of breastfeeding and complementary feeding in light of these positive changes is noteworthy.

In response to concerns about changing breast-feeding behaviours with negative consequences for infant health, a number of national and international initiatives have been implemented to promote breast-feeding. Three have been particularly important:

1. The International Code of Marketing of Breast-milk Substitutes adopted by the World Health Assembly in 198141 and subsequent relevant World Health Assembly resolutions, collectively known as The Code, provide guidelines for the marketing of breastmilk substitutes, bottles, and teats. To ensure infant feeding decisions free from the influence of marketing pressures, the Code aims to restrict such practices, including direct promotion to the public. Furthermore, World Health Assembly resolutionsb urge that there be no donations of free or subsidized supplies of breastmilk substitutes and other products covered by the Code in any part of the health care system. The Code has been adopted by many governments, either as a norm or through legislation. Despite a mixed record of compliance by infant formula manufacturers,42 it has had a major impact on the way formula is advertised and marketed. The Code has been particularly effective in the virtual elimination of the direct marketing to women who receive services through the public sector and in the restriction of marketing to health providers. The legal status of the Code, by country, is presented in Appendix 10.

b Resolution 39.28 passed in 1986 deals with specially formulated milks (so-called “follow-up milks”). Resolution 47.5 passed in 1994 deals with removing obstacles and preventing interference that mothers may face.

2. The Innocenti Declaration, which focuses on the need to protect, promote, and support breastfeeding, was signed by more than 30 countries in 1989. One operational target of this declaration is the universal implementation of the Ten Steps to Successful Breastfeeding, which forms the basis for the third major initiative: the WHO/UNICEF Baby Friendly Hospital Initiative.

3. The WHO/UNICEF Baby Friendly Hospital Initiative was endorsed by the Forty-Fifth World Health Assembly in 1992.43 This initiative has influenced the routines and norms of hospitals throughout the world through the “Baby Friendly” certification process. A hospital is designated as Baby Friendly when it has agreed not to accept free or low-cost breastmilk substitutes, feeding bottles, and teats and to implement the Ten Steps. To date, more than 14,500 hospitals in 142 countries have been certified, and many others are attempting to become certified.44

3.7 Looking Forward: The Importance of Exclusive Breastfeeding

Breastfeeding is widely practiced throughout the developing world and is actually improving in spite of demographic trends, such as urbanization, which exert a downward pressure.40 Nonetheless, there is a need to increase the duration of exclusive breastfeeding because this breastfeeding behaviour is most associated with infant health and survival. Three published studies have demonstrated the effect of breastfeeding promotion on the duration of exclusive breastfeeding.45-47 Interpersonal counselling was the key intervention. Breastfeeding promotion is one of the most cost-effective interventions to promote child health and is comparable to immunizations.48

Increasing the duration of breastfeeding does not necessarily lead to increases in the duration of exclusive breastfeeding. In Bolivia and Colombia, the duration of partial breastfeeding has increased at the same time the duration of exclusive breastfeeding has decreased. However, in countries where a concerted effort has been made to increase exclusive breastfeeding, shifts in population-level behaviours have been noted. In the Dominican Republic and Peru, the proportion of infants under four months of age who were exclusively breastfed doubled between 1991 and 1996 and between 1986 and 1996, respectively.29

The timing of interventions to promote the desired breastfeeding and complementary feeding behaviour is critical because it is likely to affect a mother’s decision-making, her motivation to overcome problems should they arise, and her persistence in maintaining a recommended behaviour despite negative influences. Therefore, interventions need to be delivered as close as possible to the time of the desired behaviour. Exclusive breastfeeding declines precipitously in the first month of life. Evidence shows that in the short term women can be encouraged to return to exclusive breastfeeding with counselling.46 However, once women cease exclusive breastfeeding they usually do not resume. Therefore, reaching women during the prenatal period, soon after delivery, and within the first month postpartum is critical to increasing the duration of exclusive breastfeeding.

The challenge from a public health perspective is to translate the vast scientific literature on breastfeeding and complementary feeding recommendations to effective interventions that are understood and accepted by the population at large. To some extent lessons learned from campaigns to promote breast-feeding can provide guidance. However, as important as breastfeeding is to infant health and survival, it is also necessary to look beyond breastfeeding and to integrate both breastfeeding and complementary feeding in campaigns to promote optimal nutrition of both the infant and young child. As noted in a recent review, providing safe and adequate amounts of foods appropriate for infants and young children is not simple.21 Complementary foods must be adequately dense in energy and micronutrients to meet the requirements of this age group. They must also be prepared, stored, and fed in hygienic conditions to reduce the risk of diarrhoea. Lastly, many feeding behaviours that affect infant and child nutritional status need further study. Qualitative and quantitative research is necessary, along with cost-effectiveness analysis. However, research is not sufficient to guarantee the success of public health interventions. The international community must work together to ensure that the same rigor applied to such research is applied to broad-scale interventions, to bring the benefits of nutrition research to those who need it most.