How Do Gut Microbes Explain Malnutrition In Children?

According to a study led by the Washington University School of Medicine, a form of severe acute childhood malnutrition is caused by bacteria living in the intestine. This discovery came as the result of a study of young twins in Malawi, in sub-Saharan Africa, and was published in the journal Science.

Childhood malnutrition is a common wellness problem in Malawi, but scientists have long been puzzled as to why one child may be afflicted by the condition but not another, even if two children live in the same household and eat the same foods. Though it is clear that poor diet plays a critical role to this wellbeing-harming condition, a lack of food alone cannot explain its causes.

The team found that a dysfunctional community of gut microbes conspire with a poor diet to trigger malnutrition, and did further studies in mice where they transplanted the gut microbes from the malnourished children into the animals. Then, when fed a nutrient-poor diet, the mice exhibited dramatic weight loss and an altered metabolism.

Currently, the standard malnutrition treatment of peanut-based, nutrient-rich therapeutic food, has helped to reduce deaths from the condition, but as the new study shows that the therapeutic food only has a transient effect on the gut microbes, new therapies need to be developed. The team discovered that the community of microbes in the intestine and their genes revert to an immature state, in the children and in the mice, once the therapeutic food is discontinued, which may explain why many malnourished children gain weight when they are treated with therapeutic food but remain at high risk for stunted growth, neurological problems and even malnutrition and death after treatment is stopped.

Senior author Jeffrey Gordon, MD, director of the Centre for Genome Sciences & Systems Biology explained, ‘The gut microbes of malnourished children and malnourished mice do not appear to mature along a normal, healthy trajectory. ‘Feeding the children and the mice a high-calorie, nutrient-rich food had a temporary, beneficial effect on their gut microbes, but not enough to repair the dysfunction. Our results suggest we need to devise new strategies to repair gut microbial communities so these children can experience healthy growth and reach their full potential.’