Scientists are becoming increasingly aware of how the human microbiome, or the collection of microbes the live on and inside of us, has a major connection to health and human physiology. Microbial engineering, which changes the structure of the microbiome through methods such as probiotics, antibiotics, and microbe transplants, has been found to be a useful strategy for improving human health, but the mechanisms underlying this improvement are still unclear and difficult to test.

Long-term therapy with estrogen and bazedoxifene alters the microbial composition and activity in the gut, affecting how estrogen is metabolized, a new study in mice found.