Mentioning: 47 - Environmental enteropathy (EE) is a poorly defined state of intestinal inflammation without overt diarrhoea that occurs in individuals exposed over time to poor sanitation and hygiene. It is characterized pathologically by small intestine villous blunting and inflammation. In children from low-income countries, it is implicated as a cause of malnutrition, oral vaccine failure and impaired cognitive development. Here we review the search for non-invasive biomarkers to measure EE non-invasively, and assess the current evidence linking EE to malnutrition, vaccine failure and neurocognitive development.