Dementia affects millions of people worldwide, and early prevention remains crucial, with current treatments still inconclusive about their benefits after symptoms appear. Meanwhile, scientists continue to focus on the role that certain lifestyle factors and daily habits play in cognitive decline.
For example, previous findings by researchers about the link between coffee consumption and the eventual development of dementia have remained controversial. And the reason is insufficient data. However, a large new study provides more reliable evidence that the caffeinated beverage can indeed protect us from the degenerative disease.
In the study, published in The Journal of the American Medical Association, American researchers analyzed data collected over four decades from more than 130,000 doctors and nurses. They were followed from middle age to old age, during which time they self-assessed their dietary patterns, collected through questionnaires.
Using this approach, the researchers also looked at changes in coffee and tea consumption over time, while also monitoring both the clinical development of dementia and other changes in participants’ cognitive function. Of the 131,821 people included in the long-term analysis, 11,033 developed dementia.
During the study, the researchers found a specific link between caffeine intake and long-term brain health. Their analysis revealed that participants who consumed more coffee had an 18% lower risk of dementia compared to those who drank less or did not drink the caffeinated beverage at all. The first group also performed better on tests of general cognitive function.
In addition to coffee, however, a similar beneficial effect on the reduced risk of developing dementia was also reported for tea. However, it should be noted that decaffeinated coffee was not associated with these benefits. Given this, to reap the benefits for cognitive function, it is best to drink caffeinated coffee – two to three cups a day. For tea, the recommended daily consumption is one to two cups.
Both beverages contain bioactive compounds such as polyphenols and caffeine, which reduce inflammation and cell damage, while also protecting against cognitive decline. Researchers call these properties “neuroprotective,” writes Fox News.
Contrary to some previous studies, higher caffeine intake did not lead to negative effects. In fact, it has a beneficial neuroprotective effect even for people with a high genetic predisposition to the disease.
Original Investigation: Zhang Y, Liu Y, Li Y, et al. Coffee and Tea Intake, Dementia Risk, and Cognitive Function. JAMA. Published online February 09, 2026. doi:10.1001/jama.2025.27259.
Illustrative Photo by Toni Cuenca: https://www.pexels.com/photo/a-cup-of-black-coffee-585754/
