Your digestive system plays host to a mind-boggling 100 trillion microbes — microscopic pinch-hitters that allow you to absorb energy from your food and churn out compounds like serotonin, which affect your mental well-being. While some of these microbes take up residence in your gut from birth, others emerge or wane depending on the lifestyle choices you make.
New research suggests that if you exercise, take antidepressants or use cannabis, your gut-bacterial balance may shift profoundly. But scientists still face a so-called black box conundrum: They’re not always sure what biological processes cause these microbial shifts or how the shifts affect other body functions. Planned larger-scale studies promise to deepen experts’ understanding of the bacterial changes your daily habits usher in, as well as the long-term health implications.
