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Feb. 23, 2026—Here's something to think about while you're sipping your morning coffee: It might help keep your brain sharper. That's the takeaway from a study published in JAMA. Researchers found that frequent coffee and tea drinkers were less prone to develop dementia than those who consumed less of these beverages.

Many years' worth of data

Researchers looked at data on more than 131,000 people in two long-running studies of nurses and other health professionals. Every two to four years, participants answered questions about their food and beverage intake. They also answered questions about their memory and thinking or took cognitive screening tests. Researchers tracked participants for 43 years. In that time, 11,033 of them got dementia.

Among the key findings:

• People who drank the most coffee and tea were less likely to get dementia than those who drank the least. The most benefit came from drinking what the researchers defined as a moderate amount: 1 to 2 cups (8 ounces) of tea a day or 2 to 3 cups of coffee a day. Drinking more than that didn't seem to provide more benefits.
• Coffee and tea drinkers showed less mental decline over time and somewhat better thinking and memory skills.
• Drinking decaffeinated coffee didn't seem to help lower dementia risk or boost thinking and memory.

How might coffee and tea help the brain?

Caffeine and other substances in coffee and tea may help the brain in different ways, the study authors noted. For instance, previous studies have found a link between coffee consumption and reduced buildup of beta-amyloid, which is found in the brains of people with Alzheimer's disease.

Caffeine also may help protect the brain from oxidative stress and inflammation, which contribute to dementia.

Polyphenols or other bioactive compounds in coffee and tea may also provide antioxidant benefits and boost blood flow to the brain. Those things could also help with memory and thinking. But more studies are needed, the authors noted.

In the meantime, this study doesn't prove that coffee and tea can keep your memory from slipping. But it does suggest one more way in which your morning cup may be linked to health benefits. Keep in mind that caffeine can make some people feel anxious or interfere with certain medications, including some Alzheimer's medicines, notes the American Medical Association. Talk to your doctor if you have questions or concerns about your caffeine intake.

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Sources

• American Academy of Neurology. "Drinking Coffee May Reduce the Risk of Neurologic Disease." https://www.brainandlife.org/articles/coffee-may-reduce-the-risk-of-neurologic-disease.
• American Heart Association. "Coffee May Protect Cognition in People With AFib." https://www.heart.org/en/news/2024/12/31/coffee-may-protect-cognition-in-people-with-afib.
• American Medical Association. "What Doctors Wish Patients Knew About the Impact of Caffeine." https://www.ama-assn.org/public-health/prevention-wellness/what-doctors-wish-patients-knew-about-impact-caffeine.
• Children and Adults With Attention-Deficit/Hyperactivity Disorder. "Can Caffeine Decrease ADHD Symptoms?" https://chadd.org/adhd-weekly/can-caffeine-decrease-adhd-symptoms/ .
• JAMA. "Coffee and Tea Intake, Dementia Risk and Cognitive Function." https://jamanetwork.com/journals/jama/article-abstract/2844764.