In 2025, Xiangyan Zhou and a team from Huazhong University of Science and Technology in China reviewed studies on how gut microbes affect depression. They explored the gut-brain axis, a two-way connection between your belly and brain, showing how gut bugs impact mood and mental health.

A July 2025 study from researchers in Japan found that certain gut bacteria may block weight loss—even when you eat well. People who ate a healthy diet but failed to lose weight had higher levels of Collinsella, a microbe linked to obesity and fat storage.