Your gut bacteria may reveal how fast your brain is aging

A new UCLA study suggests that the pace of brain aging may be connected to bacteria in the gut and the chemical compounds they produce. The findings offer a new look at biological changes that may begin long before noticeable problems with memory or thinking appear.

Scientists have used brain scans for years to estimate a person's "brain age," which can differ from chronological age. Previous research has found that when the brain appears older than expected, that pattern can be associated with poorer memory, weaker thinking skills and changes in mood.

Most earlier studies, however, focused on older adults or people who already had neurological conditions. That left an important question unanswered: does an older looking brain also matter in younger, generally healthy adults?

In a new study published in the journal eBioMedicine , UCLA Health researchers examined brain scans from nearly 1,500 adults divided across three separate groups.