Gut bacteria linked to the pace of brain aging, UCLA study finds

A UCLA Health study of nearly 1,500 adults found that people whose brains appeared older than their chronological age scored worse on working memory and executive function tests and reported more depression symptoms. Higher Brain Aging Index was tied to specific gut bacteria and metabolites, including certain fats, a cholesterol-related compound and lower estetrol levels.

• Study covered about 1,500 adults split into three groups
• Brain Aging Index (BAI) was based on resting-state brain connectivity
• Higher BAI correlated with worse working memory and more depression symptoms
• Linked pathways involve immunity, blood vessels and cellular energy use