5. Results

5.1. Cross-sectional study in 0-8-year-old children

Birth weight: 4.3% of macrobiotic children had reported birth weights below 2500 g compared to 2% in a comparable Dutch population (P < 0.02). The average birth weight was 3360 g for boys (Dutch median 3500 g; significant difference at P < 0.001) and 3250 for girls (Dutch median: 3390 g; P < 0.001).

Growth: The curve of length/height for age (Fig. 1 shows data of girls only, curves for boys were similar) followed the median of the standard until the age of 6-8 months, after which a marked decline was observed, reaching a minimum level (P10) between 1.5 and 2 years. No catch-up was observed at older ages. The curves of weight for age and arm circumference for age showed the same pattern, but now a partial return towards the P50 of the reference was observed after 2 years of age. The curve of weight for height followed the median of the Dutch reference. These findings were similar to those of earlier studies in smaller samples (Dwyer et al., 1980; Shull et al., 1977).

Relation with diet: Birth weight showed strong positive relationships with both the frequency of consumption of dairy products and of fish by the family. SDS of weight, height and arm circumference were significantly higher in children from families consuming dairy products at least three times a week compared to children from families who rarely or never used dairy products. This association was partly, but not completely, attributed to the difference in birth weight in children from families with or without regular consumption of dairy products. No association was observed between SDS and family consumption of fish, meat or eggs (Dagnelie et al., 1988).

Since the deviation from the normal growth curve occurred during the weaning period we decided to carry out a mixed-longitudinal cohort study on macrobiotic infants between 4 and 18 months of age.

Fig. 1. Height for age of girls on macrobiotic diets in the Netherlands. - - P10, P50 and P90 of Dutch reference population (Roede & Van Wieringen, 1985).

5.2. Mixed-longitudinal study in 4-18-month-old infants

Weaning diet: Macrobiotic mothers continued to breastfeed for an average of 13.6 months (control group: 6.6 months). Complementary feeding in macrobiotic infants started at a mean age of 4.8 months with water-based sieved porridges from whole-grain cereals, followed by vegetables (at 5.7 months), sesame seed (6.4 months) and pulses (8.2 months). Fruits were rarely given and animal products were avoided by most families. In the control group, complementary feeding started with fruits at a mean age of 2.7 months, followed in the next two months by vegetables and cereals (Dagnelie et al., 1989a).

Table 1 shows that for all age groups combined, the daily intake of energy and nutrients in the three cohorts of the macrobiotic group differed significantly from that of the control group. In the macrobiotic group fat intake decreased from 37% energy at an age of 6-8 months to 17% at 14-16 months, due to the fact that fat from breastmilk was not replaced by other fat sources during weaning. With the decreasing amount of breastmilk, animal protein intake decreased from 7 g/d at 6-8 months to 2 g/d at 14-16 months, as compared to an increase from 18 to 28 g/d in the control group. The intake of calcium, riboflavin and vitamin B₁₂ by macrobiotic infants was considerably below that of the control group (Dagnelie et al., 1989a).

Table 1. Intake of energy and nutrients by infants (6-16 months of age) on macrobiotic and omnivorous (control) diets

		Macrobiotic group (n = 49) Mean ±SD	Control group (n = 57) Mean ±SD
Energy (MJ)		3.0 ±0.5	3.6 ±0.7 a
En. density (kJ/g)		2.4 ±0.3	3.4 ±0.5 a
Protein
	Animal b (g)	4 ±3	24 ±8 a
	Total (g)	20 ±7	32 ±10 a
	%Energy (%)	11 ±3	15 ±3 a
Fat (g)		22 ±9	30 ±7 a
	%Energy (%)	28 ±12	32 ±7 a
Carbohydrate
	Oligosacchar. (g)	47 ±20	70 ±17 a
	Polysacchar. (g)	63 ±41	45 ±18 a
	Total (g)	110 ±29	115 ±25
	%Energy (%)	61 ±10	54 ±5 a
Dietary fibre (g)		13 ±7	7 ±3 a
Dietary fibre (g/MJ)		4.1 ±1.9	2.0 ±0.7 a
Calcium c (mg)		280 ±68	751 ±230 a
Iron (mg)		5.1 ±2.8	4.0 ±1.6 a
Thiamine (mg)		0.6 ±0.3	0.4 ±0.1 a
Riboflavin (mg)		0.4 ±0.1	1.1 ±0.3 a
Vitamin B12 (pa)		0.3 ±0.2	2.9 ±1.3 a
Vitamin C (mg)		53 ±22	77 ±40 a

a Difference significant at P < 0.001.
^b Including breast milk.
^c Based on preparation of foods with water containing 28 mg of calcium per liter.

Growth: Growth curves of length and weight for age for both groups are presented in Fig. 2. Deviation in linear growth from the P50 of the reference occurred in the macrobiotic infants from four months onwards. From 16 months of age linear growth stabilized at the 10th percentile of the Dutch references, whereas in the control group growth velocities were similar to the Dutch references (Dagnelie et al., 1989b). Comparison with birth weight data of the macrobiotic infants showed that retardation of weight growth already occurred before the age of 4 months. Weight growth was most depressed between 8 and 14 months, while stabilization at the P3 level occurred between 14 and 18 months. As shown in Table 2 for the combined cohorts, growth velocities for weight, length and arm circumference (expressed as units per year) were significantly lower in the macrobiotic group.

Relation with diet: A multiple regression analysis was carried out to determine whether the observed growth retardation could be explained by a reduced intake of energy or protein by the macrobiotic infants. Both the energy intake and the protein content of the macrobiotic diet contributed independently to growth in weight and arm circumference (Dagnelie et al., 1989b). In contrast, growth in length was only associated with the protein content of the diet.

Clinical and biochemical observations (methods of blood analysis) are described in Dagnelie et al. (1989a,c). The low riboflavin intake by the macrobiotic children was reflected by an elevated activity coefficient of erythrocyte glutathion reductase (EGR) (Dagnelie et al., 1989a). Iron deficiency was observed in 15% of the macrobiotic infants, versus no infants in the control group. As a consequence of the extremely low intake of vitamin B₁₂ in macrobiotic infants, we found low plasma vitamin B₁₂ concentrations which were associated with a rise in mean corpuscular volume (MCV) (Dagnelie et al., 1989c). In summer, 28% of macrobiotic children showed clinical symptoms of rickets, and in winter 55%. Our data indicated that the high prevalence of rickets is the result of long-term depletion of body calcium stores caused by a diet with a low calcium and a high fiber content, in combination with vitamin D deficiency during a part of the year. No indication of an effect of the duration of breastfeeding on the presence of rickets was found (Dagnelie et al., 1990). Major skin and muscle wasting was present in 30% of the macrobiotic infants. Growth velocities in weight and height were lower in these wasted infants (P < 0.05). Infants with major skin and muscle wasting were slower in locomotor development than the other macrobiotic infants (P = 0.05) (Dagnelie et al., 1989b). The macrobiotic group was significantly later in gross motor development (P < 0.001) and, to a lesser degree, in speech and language development (P < 0.03) (Dagnelie et al., 1989b).

Fig. 2. Growth curves (length for age, weight for age) of infants on macrobiotic or on omnivorous (control) diets in the Netherlands. - - - P10, P50 and P90 of Dutch reference population (Roede & Van Wieringen, 1985).

Figure (2a)

Figure (2b)

Table 2. Growth velocities (units per year) of infants (4-18 months of age) on macrobiotic and omnivorous (control) diets

	Macrobiotic group (n = 52) Mean ±SD	Control group (n = 57) Mean ±SD
Weight (kg)	3.1 ±1.6	4.4 ±1.4 a
Length (cm)	13.2 ±3.9	16.7 ±3.1 a
Arm circumference (cm)	1.0 ±2.2	2.3 ±2.4 b
Weight-for-length (kg)	2.4 ±1.9	3.3 ±1.8 c

Differences between groups significant at ^a P < 0.001, ^b P <0.003, ^c P < 0.02.