The contribution of breast milk to toddler diets in western Kenya.

OBJECTIVE To understand the relative contributions of breast milk and the weaning diet to overall nutrient intake, with a view to designing and implementing appropriate programmes to improve complementary feeding in developing countries. METHODS Complementary food intake was measured in a sample of 250 toddlers (mean baseline age: 13.9 +/- 2.4 months) using 24-h dietary recall interviews administered once every 3 weeks over a 6-month period. Breast-milk intake over a 24-h period was measured using the test-weighing method in a subsample of 50 children. Regression effects of age and sex on observed milk intakes were estimated and imputed to the whole sample to estimate mean intake over the observation period. Total energy and nutrient intakes were evaluated for adequacy with reference to published estimates of toddler requirements. FINDINGS Total energy intake (1029 kcal/day) was adequate, with breast milk supplying an average of 328 kcal/day (32%), but vitamin A, riboflavin, calcium, iron and zinc intakes were below current estimates of required intakes. Observed limitations in nutrient intake were consistent with the finding that almost half of the toddlers were stunted. The prevalence of wasting was 6% at baseline and 4% at final assessment. Although food consumption increased when breastfeeding stopped, it could not fully compensate for the fat and vitamin A previously supplied by breast milk. CONCLUSIONS The nutritional role of mother's milk in the second year is inversely related to the adequacy of the complementary diet. In this study, breast milk was an irreplaceable source of fat and vitamin A. When the weaning diet is inadequate for key nutrients because of low intake or poor bioavailability, breast milk assumes greater nutritional significance in the second year of life but does not guarantee adequate nutrient intakes.