Coffee and tea associated with lower dementia rates.

A study of more than 130,000 U.S. adults (1980–2023) found that caffeinated coffee and higher tea intake were associated with lower dementia rates and better cognitive test performance, while decaffeinated coffee showed no association.

A new observational study tracked dietary intake of caffeinated coffee, decaffeinated coffee, and tea in a U.S.-based group of adults and compared those records with dementia diagnoses and performance on neuropsychological tests. Researchers analyzed data covering roughly 1980 through 2023 for more than 130,000 people. After adjusting for confounding factors, the analysis found lower dementia rates and better cognitive test scores linked to caffeinated coffee and higher tea intake. The study did not find the same associations for decaffeinated coffee. Authors note that the design is observational and does not establish cause-and-effect. Key findings: - The analysis included more than 130,000 adults with dietary and cognitive data collected between 1980 and 2023. - Reported dementia incidence was lower among caffeinated coffee drinkers (141 cases per 100,000 person-years) compared with non-drinkers (330 cases per 100,000 person-years). - Higher tea intake showed similar associations with cognitive outcomes as caffeinated coffee. - Decaffeinated coffee was not associated with lower dementia risk or better cognitive performance in this study. - The most pronounced associations were observed at about 2–3 cups per day of caffeinated coffee or 1–2 cups per day of tea. Summary: The study reports an association between caffeinated coffee or higher tea intake and lower dementia rates and improved cognitive test results, while decaffeinated coffee showed no link. Because the research is observational, researchers emphasize that it cannot prove causation and that it is unclear whether caffeine, a metabolite, or another compound explains the findings. Further research is needed to explore mechanisms and to test whether the association holds in other populations and study designs.