What is dysbiosis?
Dysbiosis is an imbalance in the community of microbes living in your body, for example in your gut or mouth, where helpful species decline and harmful ones gain ground.
Think of a garden where weeds slowly crowd out the flowers. Nothing is "broken" in one dramatic moment, but the balance tips, and the garden stops working the way it should.
Why it matters for aging
In the gut, dysbiosis is linked to inflammation, metabolic problems and weaker immunity. In the mouth, a shift toward plaque-forming bacteria drives cavities and gum disease. Scientists added dysbiosis to the list of hallmarks of aging in 2023.
Because it's still hard to define a single "healthy" microbiome, the most reliable advice is simple: eat a wide variety of fiber-rich plants and fermented foods, move regularly and look after your teeth and gums.
A common myth
Dysbiosis can be fixed quickly with a probiotic pill.
Probiotics help in some specific situations, but long-term balance depends mostly on diet, especially fiber and varied plants, plus sleep, exercise and avoiding unnecessary antibiotics.
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Updated Nov 9, 2026 · All terms