The bacteria that call your gut home can have a tremendous impact on your overall health, but exactly how the bugs do so is a web that’s still being untangled. To investigate, researchers at Harvard Medical School have deleted a single gene from one gut bacteria species and found that it alters the metabolism of the host, reducing their weight gain.
In recent years, scientists have implicated a person’s gut microbiome in their likelihood of developing diabetes, obesity, multiple sclerosis, Alzheimer’s and even depression, but it’s tough to figure out which bacteria are responsible for which effects, and how they trigger them.
For the new study, the researchers focused on a single aspect of the gut environment, and investigated how bacteria can change that to affect the host’s metabolism. The aspect in question is a group of substances called bile acids, and imbalances in these are thought to contribute to obesity. Gut bacteria can either help or hinder that balance by chowing down on these acids, using enzymes known as bile salt hydrolases.