Severe malnutrition has long been thought to stem simply from a lack of adequate food. Scientists now understand that the condition is far more complex. Indeed, it is not uncommon for a family with multiple children to have only one child who is malnourished, even though the children eat a similar diet and live in the same household. This has led scientists to suspect that other factors may be involved. Gordon and his group theorize that an imbalance of certain types of gut microbes conspires with other factors, such as a poor diet and infection with bugs that cause diarrhea, to trigger malnutrition.
The human body contains ten times as many microbial cells as human ones, with large numbers residing in the intestines. While some microbes cause illness, most perform vital tasks to ensure the body functions optimally, such as digesting complex carbohydrates found in grains, fruits and vegetables, which the body can't break down on its own. The nutrients and calories extracted by the microbes are used either as energy or stored as fat.