Effects of season and illness on the dietary intake of weanlings during longitudinal studies in rural Bangladesh.

Longitudinal, quantitative studies of the dietary intake of 70 weanlings between five and 30 months of age from two Bangladeshi villages have been analyzed to determine the effects of season and illness on dietary intake. During 1014 days of observation, all foods consumed by the children were weighed by a field worker present in the home; 24-hour breast milk intake was estimated from 12-hour test weighings. Inter-individual differences explained 29% to 50% of the variance in consumption of selected nutrients and foods during 632 studies conducted when children were free from diarrhea and fever. Multiple linear regressions controlling for inter-individual differences indicated that 60-day seasonal periods explained a significant proportion of the variation in intake. Average energy consumption (kcal/kg/d) was approximately one-third greater during the post-harvest periods than during the pre-harvest monsoon period. Breast milk intake varied similarly even after controlling for age-related decreases. Consumption of rice and wheat, the major non-breast milk sources of energy and protein, had distinct seasonal patterns, thus limiting the overall seasonal variability in cereal intake. Older children, particularly boys, benefited more from the post-harvest relative abundance of food. The intake of most nutrients was significantly depressed by approximately 10% during febrile illnesses. Minor decreases in intake with other illnesses were not statistically significant.