The study was carried out by scientists from Mass General Brigham, Harvard T.H. Chan School of Public Health, and the Broad Institute of MIT and Harvard, using data from two major long‑running research projects: the Nurses’ Health Study (NHS) and the Health Professionals Follow‑Up Study (HPFS).
According to Dr. Daniel Wang, MD, ScD, associate scientist with the Channing Division of Network Medicine at Mass General Brigham and assistant professor at Harvard Medical School, the research team began the study with a simple question: “When searching for possible dementia prevention tools, we thought something as prevalent as coffee may be a promising dietary intervention.”
He added that the unique long‑term data available from NHS and HPFS allowed the team to examine diet and brain health over decades.
Across the study period, 11,033 participants developed dementia. Those who regularly consumed caffeinated coffee showed lower rates of dementia compared with people who rarely drank coffee.
These coffee drinkers also demonstrated slower cognitive decline and better performance on memory and thinking tests over time.
The benefits were also seen among tea drinkers. In contrast, decaffeinated coffee did not show the same protective effects, suggesting that caffeine or other active compounds in caffeinated drinks may be responsible for the observed benefits.
Lead author Yu Zhang, MBBS, MS, a PhD student at Harvard Chan School and research trainee at Mass General Brigham, said the results were consistent even among people with genetic predispositions to dementia.
“We also compared people with different genetic predispositions to developing dementia and saw the same results meaning coffee or caffeine is likely equally beneficial for people with high and low genetic risk,” Zhang explained.
Researchers emphasize that while the findings are encouraging, they do not prove that coffee or tea prevents dementia outright, and that overall lifestyle and diet remain important. The study adds to growing evidence that small daily habits, including moderate caffeinated beverage intake, could contribute to healthier aging.
Leave a Reply