Most bacteria in our intestines are still an unknown for scientists

Although some gut bacteria such as Akkermansia muciniphila have been shown to improve some features of obesity, a lot of the bacteria in our gut are yet to be identified.

That is because they cannot be cultivated outside the gut, their genetic material does not match microbial genomes available in current databases and we still do not know everything they can do for us.


A new bacterium is found in the gut of 70% of healthy people and might protect against obesity-associated glucose imbalances

A team of scientists reported the discovery of the new bacterium Dysosmobacter welbionis J115T in 2017 from the gut of one healthy subject. As it was closely related to other gut bacteria related to leanness, they decided to explore its benefits for host metabolic health.

Writing in Gut, Patrice D. Cani and colleagues showed that D. welbionis J115T is found in up to 70% of the healthy population and that lower levels are associated with higher body mass index, higher fasting glucose levels and higher glycated hemoglobin, which is an indicator of long-term presence of excess glucose in the blood.

Supplementation with the live bacterium reduced body weight and fat mass in mice fed a high-fat diet. However, the pasteurized bacteria abolished beneficial metabolic effects.


The beneficial effects of the new bacterium are not limited to the gut

Beyond reducing fat mass gain, treated mice showed improved glucose tolerance, decreased levels of inflammation and increased activity of brown-adipose tissue primarily involved in thermoregulation energy balance.

The next step for scientists is to find out the health benefits of the new bacterium in humans as regards obesity and related metabolic diseases.


See the process of identification of the new bacterium and its anti-obesity effects in this video from Francois Grimonprez:




Le Roy T, Van der Smissen P, Paquot A, et al. Dysosmobacter welbionis gen. nov., sp. nov., isolated from human faeces and emended description of the genus Oscillibacter. Int J Syst Evol Microbiol. 2020; 70(9):4851-4858. doi: 10.1099/ijsem.0.003547.

Le Roy, de Hase EM, Van Hul M, et al. Dysosmobacter welbionis is a newly isolated human commensal bacterium preventing diet-induced obesity and metabolic disorders in mice. Gut. 2021. doi: 10.1136/gutjnl-2020-323778.