People who drink a few cups of tea or coffee each day may face a lower risk of dementia, scientists say. A large US study found that people who drank two to three cups of caffeinated coffee or one to two cups of caffeinated tea daily had a 15–20% lower dementia risk. Researchers tracked more than 130,000 adults for up to 40 years. The results appeared in the Journal of the American Medical Association.
Caffeinated coffee drinkers also showed slightly slower cognitive decline than people who drank decaf. Tea and coffee contain caffeine and polyphenols that may protect the brain by improving blood flow and reducing inflammation. Lead author Yu Zhang of Harvard University said the study could not prove cause and effect. He warned that other lifestyle factors may explain the link.
Experts say caffeine has both positive and negative effects on the brain. Researchers stress that exercise, healthy diet, good sleep, and blood pressure control remain key to protecting brain health.
