This report suggests that a key cause of child undernutrition is a subclinical disorder of the small intestine known as tropical enteropathy, caused by faecal bacteria ingested in large quantities by young children living in conditions of poor sanitation and hygiene. The author proposed that the primary causal pathway from poor sanitation and hygiene to undernutrition is tropical enteropathy and not diarrhoea as is often assumed.

The author concludes that interventions focused on gut microbial populations and improved drinking water quality might be important, together with continued efforts to improve infant diets and that prevention of tropical enteropathy, which afflicts almost all children in the developing world, will be crucial to normalise child growth. Provision of toilets and promotion of handwashing after faecal contact could reduce or prevent tropical enteropathy and its adverse effects on growth.