Overview
- Participants who drank about 2–3 cups of caffeinated coffee or 1–2 cups of tea daily had the lowest observed dementia risk, with the highest coffee intake tied to an 18% lower risk versus the lowest intake.
- Decaffeinated coffee showed no protective association, pointing researchers toward caffeine and other bioactive compounds as potential drivers that require further study.
- The study pooled roughly 131,800 U.S. health professionals followed for up to 43 years, identifying 11,033 dementia cases and finding slightly better objective cognitive performance and slower decline among higher consumers.
- The association appeared consistent across genetic risk levels, including in people carrying APOE4, according to the authors.
- Experts and the study team cautioned that the effect is modest and observational, noting limitations such as self-reported intake and cohort composition, and they urged prioritizing proven measures like exercise, healthy diet, and adequate sleep.