The more we learn about the communities of microorganisms that live in our bodies, the more the microbiome reveals itself to be a rich source of clues for how to treat a wide range of afflictions. Now new research suggests that the trillions of microorganisms inhabiting the human gut might even show the way to counteract one of most devastating health problems facing the world: childhood malnutrition.

Some 180 million children suffer from not having enough to eat, and more than three million die every year as a result. It also causes stunting, a largely irreversible condition that hampers physical and cognitive development and can make affected individuals more susceptible to disease.

Three new studies published last week in the prominent journals Cell and Science indicate that the microbiomes of undernourished children fail to develop properly, compounding the problem of malnutrition and contributing to its long-term consequences. And perhaps the underdeveloped microbiome is to blame for the fact that dietary supplements often don’t work against childhood undernutrition.

A nurse measures the arm of a severely malnourished child at a clinic in North Darfur.

A few years ago researchers analyzed data from fecal samples taken from malnourished children in Malawi and found that that these children grew up with “immature” gut microbiomes relative to individuals who were not malnourished as children.

The same group has now found that mice engineered to have this “immature” human gut microbiome grew poorly compared to mice given the microbiomes of healthy children. Another group published a similar result in mice, and found that the microbes influence growth hormones in some way. Finally, a third study found that the breastmilk of mothers of malnourished children, also in Malawi, contained less of a particular sugar molecule known to be crucial to the early development of the gut microbiome.

These results are preliminary, and it’s not yet clear how to turn insights like these into new treatments for people. But we’ve already seen that therapies based on adding good bacteria back to the gut can work, so there’s reason to think that research like this could lead to a weapon against the effects of malnutrition.

(Read more: The Atlantic, Science, “Companies Aim to Make Drugs from Bacteria That Live in the Gut”)