Study findings published in Nature reveal how malnutrition damages healthy gut bacteria in children

Nasmeen Ahmed

The findings of a novel study undertaken by researchers at icddr,b and collaborating   institutions have shown that healthy gut bacteria damaged due to malnutrition do not recuperate even after children are given nutritious therapeutic food supplements. The findings, published in the prestigious journal Nature in June, may help researchers understand why millions of malnourished children worldwide continue to suffer from stunting and don’t completely recover from malnutrition despite dietary interventions.  Healthy microbes present in the human gut are essential for extracting and metabolising nutrients from food. In malnourished children these microbes are not healthy enough to process the essential nutrients.

This study was conducted at icddr,b in Dhaka, where 64 children experiencing severe acute malnutrition and aged 6 to 20 months were compared with 50 healthy children coming from similar socioeconomic backgrounds. The malnourished children were provided with either Plumpy’Nut, a peanut based enriched food supplement used worldwide for the treatment of malnutrition, or a nutritious diet based on rice and lentils. The researchers also collected stool samples of all the children before they started receiving the therapeutic food and periodically after that for up to two weeks until they achieved their expected weight. The researchers continued to take the stool samples every month for four months and tested them for bacterial species that indicate healthy gut microbiota and normally develop within the first two years of life.
The severely malnourished children included in this study had either been admitted to icddr,b’s Nutritional Rehabilitation Unit or were enrolled in the ongoing icddr,b MAL-ED (Malnutrition and Enteric Diseases) project located in Mirpur, a suburb of Dhaka city.
The study findings show that while the healthy children continued to develop healthy guts, the malnourished children gained weight but only temporarily experienced an improvement of their gut. Once the dietary interventions ceased, their guts also reverted back to the immature state prior to treatment. The study shows that childhood malnutrition has a damaging effect on gut health that does not completely recover after nutritional interventions. Not only are malnourished children underdeveloped in terms of physical growth (weight, height and body mass) their intestinal bacterial communities are also immature, thus causing a vicious cycle of childhood malnutrition.  
Led by co-author Dr Tahmeed Ahmed, the icddr,b study team also included four other Bangladeshis: Associate Scientist Dr Sayeeda Huq, Senior Scientist Dr Md Rashidul Haque, Assistant Scientist Dr Mustafa Mahfuz and Statistician Mr Mohammed Ashraful  Alam
Dr Ahmed, who is also Director of icddr,b’s centre for Nutrition and Food Security said, “This research has contributed immensely to what we know about the mechanisms operating in acute malnutrition. I believe it will open up new vistas for simplifying treatment of this dreadful condition that affects millions of children globally.”  
This study was a collaboration between icddr,b, the Center for Genome Sciences and Systems Biology at Washington University, Department of Anthropology, New School for Social Research in New York and the Departments of Medicine, Microbiology and Pathology at the University of Virginia School of Medicine. Funding was provided by the Bill & Melinda Gates Foundation, the International Atomic Energy Agency, and the US National Institutes of Health.
The findings of the study received extensive coverage in international news outlets such as BBC Online,  The New York Times,  The Indian Express, The Global List,  BioPortfolio and NBC News.
To find out more about the study please contact Nasmeen Ahmed Senior Communications Manager, icddr,b.