In Bangladesh, a health worker measures a child’s arm to monitor the progress of a malnutrition supplement study.
MUNIR UZ ZAMAN / AFP via Getty Images
By Elizabeth Pennisi
To save a hungry child, caregivers have long used one of the obvious treatments: food. But a new study suggests that feeding their gut bacteria may be just as important – or even more important – than feeding their stomachs. In a head-to-head comparison with a leading malnutrition treatment, a new supplement designed to promote beneficial gut bacteria has led to signs of improved growth and more weight gain, despite 20% fewer calories. The study also highlights how important intestinal bacteria – the so-called microbiome – can be for human health.
“This is an exciting study that promises to give hope to millions of acutely malnourished children,” said Honorine Ward, a scientist at Tufts University of Medicine who was not involved in the work.
About 30 million children worldwide are so hungry that their bodies are wasted. Their growth slows down, their immune system does not work well and their nervous systems do not develop properly. To combat malnutrition, health clinics often provide pre-packaged, ready-to-use supplemental food (RUSF), which is easy to store and easy to store. But health improvements of malnourished children are seldom permanent, and many never fully recover, even after they have eaten enough. “This is a problem that previously did not have an available solution,” said Ruslan Medzhitov, an immunologist at Yale University who was not involved in the work.
Jeffrey Gordon, a microbiologist from the Washington University School of Medicine in St. Louis, has spent more than ten years studying the role that the microbiome plays in the recovery of malnutrition. He and his colleagues discovered that 15 key bacteria are needed for normal growth in mice, pigs and to some extent in humans, and that children whose microbiomes do not become ‘mature’ to include these species do not recover from malnutrition not, as well as children whose intestinal bacteria do mature. “Current therapies do not repair this disrupted microbiome,” Gordon explains.
That’s why he and Tahmeed Ahmed, an expert scientific malnutrition who heads the International Center for Diarrhea Research in Dhaka, Bangladesh, tried to figure out with colleagues which of half a dozen combinations of foods are readily available, the growth of these healthy people has encouraged bacteria. In the new study, they tested their best candidate: a complex blend of chickpeas, banana, soy and peanut butter and oils that made them microbiota-targeted supplement foods no. 2, or MDCF-2.
About 120 toddlers with malnutrition from a slum in Dhaka received MDCF-2 or the standard RUSF supplement twice daily for 3 months. Every two weeks during the treatment, and again 1 month after the end of the treatment, the researchers weighed and measured the children, sampled their blood and analyzed the bacteria in their feces.
Not only did MDCF-2 increase growth-linked blood components, such as proteins needed for proper bone development, the nervous system and the immune system, but it also led to a growth rate twice as high. to change in a weight-to-height score, as in those receiving RUSF, the researchers reported today in The New England Journal of Medicine. What’s more, 21 types of beneficial bacteria have increased in abundance. Improved growth in children continues even after treatment is stopped. “A small amount of this nutritional supplement can cure malnutrition in children,” Ahmed concludes.
But becoming standard treatment can take years, Ahmed says. First, the team needs to come up with a simpler formulation that can be stored for months – at the moment, the supplement is being made fresh – and it’s easy for mothers to obtain and use. In addition, larger trials need to be conducted in other countries, with children being followed up to five years to see if the beneficial effects continue, Ward says.
Meanwhile, the work offers stimulating tips on how gut bacteria can alter growth. “Different bacteria are beneficial or detrimental at different stages of development,” says Medzhitov. For example, a bacterium linked to the beneficial effects of breastfeeding, Bifidobacterium longum, was associated with less improvement in the children in the study. This finding paves the way for the development of disease-specific interventions to form the microbiome, Ward adds.
Until that happens, Gordon and Ahmed continue to refine their formulation, keeping an eye on other countries – and communities – for their studies. “I think the remaining challenges are mostly logistical,” Medzhitov says. Gordon agrees, adding that their findings still amount to a simple message: “Healthy children depend on a healthy microbiome.”