The nutritional impact of seasonality in children and adults of rural Ethiopia.

A survey of the nutritional status of subsistence farmers was conducted over 13 months in a rural area of Ethiopia characterized by moderate climatic seasonality and intensive land exploitation. Bi-monthly questionnaires on food consumption, time allocation, agricultural production and cash flow were administered to 203 households and anthropometry performed on 1407 individuals. Comparison of post-harvest and pre-harvest anthropometry was made on 672 individuals (48% of the sample). In children, seasonal changes in the Z-score of weight-for-height were small and not significant. Height growth velocity showed instead a marked seasonal pattern, with values close to normal (-0.2 SD units) in July to December, a period characterized by better food availability, and lower values (-3.0 SD units) in January to June, a period characterized by intensive farm labour and heavy rains. Among the adults, body weight was highest in the post-harvest season (December) and decreased by 1.5 +/- 2.3 kg in men and 1.3 +/- 2.6 kg in women to the yearly minimum in the pre-harvest season (June). The paper shows that in this area children and adults both suffer from exposure to seasonal energy stress. The change in weight-for-height Z-score observed in children and the body weight loss observed in adults was greater in individuals of low socio-economic status and, within the same socio-economic level, in individuals with better nutritional status.