(HealthDay News) — Researchers say they have successfully linked certain byproducts of digestion to the risk of excess body fat. The findings were published in the April 29 issue of Science Translational Medicine.
For the study, 2,324 American and British participants provided urine samples, as well as information regarding their diet, exercise habits, blood pressure, and body mass index (BMI). The team of researchers constructed an in-depth biochemical “map” that tracked the way food is processed and broken down by the body. This enabled the investigators to take a snapshot of the end product of digestion: metabolites. More than two dozen of these metabolites were highly correlated with diet. Some were associated with having a high BMI, while others were associated with having a low BMI.
Ultimately, nine metabolites appeared to be linked to having high BMI. These particular metabolites had been produced by microbes commonly found in the human gut that are involved in the digestion process. Another metabolite described as a sign of consumption of red meat was also linked to a high BMI. By contrast, a different metabolite that indicates the consumption of citrus fruits was linked to having a low BMI.
About half the cited molecules had not previously been linked to obesity risk, study coauthor Jeremy Nicholson, Ph.D., told HealthDay. Nicholson heads Imperial College London’s department of surgery and cancer, and is the director of its Medical Research Council-National Institute for Health Research National Phenome Centre. What’s more, his team’s mapping effort suggests that about 5 to 6 percent of obesity risk can be explained by the activity of microbes in the gut. “That means that the bugs in our gut, and the way they interact with the food we ingest, play a three to four times more important role in obesity risk than our genetic background,” Nicholson said.