Short-course zinc prophylaxis is known to reduce the incidence and severity of diarrhoea, but its effects have only been studied in children >12 months old. Malik et al. conducted a randomized, double-blind, placebo-controlled trial to investigate the effects of a short course of prophylactic zinc supplementation in infants aged 6–11 months. 272 infants from an urban resettlement colony in Delhi, India, were enrolled in the study, and were randomly allocated to receive either 20 mg zinc or placebo every day for 2 weeks. Zinc supplementation was found to reduce the number of episodes of diarrhoea and the number of days that a child had diarrhoea. The authors conclude that these findings could be important in populations with a high prevalence of wasting and stunting.