A Cochrane review included 8 studies with a total of 1 243 children on community-based supplementary feeding for promoting the physical growth of children under 5 years of age in low and middle income countries. Supplementary feeding was defined as the provision of extra food to poor children or families beyond the normal ration of their home diets. There were high levels of clinical heterogeneity in the participants, interventions and outcome measures across studies. Nevertheless, in order to quantify pooled effects of supplementary feeding the studies were combined according to prespecified characteristics which were the children's age (younger or older than 24 months), their nutritional status at baseline (stunted or wasted, or not stunted or wasted) and the duration of the intervention (less or more than 12 months). A statistically significant difference of effect was only found for length during the intervention in children aged less than 12 months (MD 0.19 cm, 95% CI 0.07 to 0.31; 2 studies, n=795). Based on the summary statistic calculated for each study, the MD between intervention and control groups ranged from 0.48 cm (95% CI 0.07 to 0.89) to 1.3 cm (95% CI 0.03 to 2.57) after 3 and 12 months of intervention, respectively. Data on potential adverse effects were lacking.
Comment: The quality of evidence is downgraded by study limitations (unclear allocation concealment and lack of blinding), and by inconsistency.