How an aging immune system loses control over the gut microbiome

Trillions of microorganisms live in the human gut, collectively forming the gut microbiome. They support important bodily functions, including digestion, metabolism, and the immune system. While this microbial community remains stable for many years, it often becomes unbalanced with age: diversity declines, certain microorganisms gain the upper hand, and the risk of inflammation increases. Why the gut microbiome loses its balance with age is one of the central unanswered questions in aging research.