2 to 3 Cups of Coffee a Day May Reduce Dementia Risk. But Not if It’s Decaf.
One to two cups of caffeinated tea per day helps too, researchers found after following nearly 132,000 people for 40 years.
By Pam Belluck
(Pam Belluck wrote this while drinking three cups of caffeinated coffee and two cups of decaf.)
A large new study provides evidence of cognitive benefits from coffee and tea — if it’s caffeinated and consumed in moderation: two to three cups of coffee or one to two cups of tea daily.
People who drank that amount for decades had lower chances of developing dementia than people who drank little or no caffeine, the researchers reported. They followed 131,821 participants for up to 43 years.
“This is a very large, rigorous study conducted long term among men and women that shows that drinking two or three cups of coffee per day is associated with reduced risk of dementia,” said Aladdin Shadyab, an associate professor of public health and medicine at the University of California, San Diego, who wasn’t involved in the study....
Some previous studies haven’t found cognitive benefits from caffeine, but those studies often had limitations like shorter time periods or one-time assessments of diet, experts said. The new study aligns with a growing body of research “that’s suggested caffeinated coffee may reduce risk of age-related chronic diseases,” Dr. Shadyab said...
Compared with people who consumed virtually no caffeine, people who drank between one and five eight-ounce cups of caffeinated coffee had about 20 percent less dementia risk. Those who drank at least one cup of caffeinated tea daily had about 15 percent less risk.
But beyond two and a half cups of coffee daily, the advantage plateaued, possibly because humans cannot metabolize any more of the bioactive compounds in coffee and tea, said the study’s senior author, Dr. Daniel Wang, an epidemiologist specializing in neurodegenerative diseases at Mass General Brigham health system.
https://www.nytimes.com/2026/02/09/health/coffee-tea-dementia-risk.html