Removal of Certain Gut Bacteria Leads to Weight Gain

Rockville, Md. (April 22, 2021)—Researchers from the Medical College of Wisconsin (MCW) report in new research that gut bacteria burn a significant percentage of calories from food that we ingest. Those calories then get absorbed and converted to adipose (fat) tissue. The findings also show that surgical removal of part of the intestine leads to weight gain because that specific section contains bacterial biomass. In addition, the study shows that drugs or a high carbohydrate diet can alter the gut bacteria enough to affect calorie consumption by the bacteria that remain in the system, which leads to weight gain.  

“The purpose of the work is to determine how altering gut bacteria leads to changes in body weight,” said corresponding author John Kirby, PhD, a professor at MCW. “It is known that antibiotics and other drugs lead to weight gain, so we sought to determine a mechanism.  Conversely, it is known that certain types of bariatric surgery lead to weight loss and so we wondered if the mechanism also depends on gut bacteria.”

Read the full article, “Gut Microbiota Represent a Major Thermogenic Biomass,” published ahead of print in Function. Contact the APS Communications Office or call 301.634.7314 to schedule an interview with a member of the research team.