Coffee May Support Healthy Brain Aging—But More Isn’t Better

Key takeaways

• In a study following U.S. adults for up to 43 years, caffeinated coffee was associated with healthier cognitive aging and a lower likelihood of serious impairment in memory and thinking.

• The strongest associations appeared at two to three cups daily. Higher intake did not appear to offer additional benefits.

• Tea showed a similar favorable pattern at one to two cups daily, while decaffeinated coffee did not show the same association.

• The findings are observational. They do not prove that coffee protects the brain or that caffeine explains the connection.

More than a morning boost?

Coffee’s immediate appeal is easy to understand: it helps people feel more alert. Whether that daily habit relates to brain health decades later is a different question.

Researchers examined coffee and tea consumption in U.S. adults followed for as long as 43 years. Regular caffeinated coffee drinkers had more favorable long-term cognitive outcomes than people who rarely or never drank it.

The association also appeared across different levels of genetic susceptibility. That suggests the pattern was not limited to people with a relatively favorable inherited profile—but it does not mean coffee overrides genetic risk.

A modest difference people could notice

The findings extended beyond formally diagnosed impairment.

Among participants consuming higher amounts of caffeinated coffee, 7.8% reported declines in their memory or thinking, compared with 9.5% of those who rarely or never drank it.

These were subjective reports: changes people noticed themselves, not necessarily difficulties confirmed through testing.

That distinction matters. Feeling more forgetful is not the same as losing the ability to manage everyday life. Still, examining both outcomes gives researchers a broader picture than either measure alone.

Two to three cups—not “the more, the better”

The most favorable associations appeared at two to three cups of caffeinated coffee daily. For tea, the corresponding range was one to two cups.

Drinking more did not appear to provide further benefits.

These ranges describe the pattern observed—not a proven optimal dose. The study did not assign participants to drink specific amounts, so it cannot establish that increasing someone’s intake would improve their future brain health.

The decaf difference raises a question

Decaffeinated coffee did not show the same favorable association.

That makes caffeine an interesting candidate, but not a confirmed explanation. Regular and decaf drinkers may differ in other ways, including why they choose one over the other.

The tea findings do not settle the question either: researchers did not distinguish between caffeinated and noncaffeinated tea.

The useful next step is to investigate which components of these beverages might matter—and whether the apparent benefits reflect the drinks themselves, the people who choose them, or both.

What this means for your routine

This is encouraging evidence for people who already enjoy moderate amounts of coffee or tea. It is not a reason to force a habit that does not suit you.

The study also does not show that switching from decaf to regular coffee improves cognition. An absent association for decaf is not evidence that decaf is harmful.

Most importantly, a beverage habit should not be mistaken for a stand-alone strategy for preserving memory.

The takeaway

Over decades of follow-up, moderate caffeinated coffee and tea consumption tracked with more favorable cognitive outcomes.

The strongest message is not to drink more. It is that a familiar daily ritual may carry a long-term brain-health signal—one that still needs to be separated from cause and effect.

References:

1. Yu Zhang, Yuxi Liu, Yanping Li, Yuhan Li, Xiao Gu, Jae H. Kang, A. Heather Eliassen, Molin Wang, Eric B. Rimm, Walter C. Willett, Frank B. Hu, Meir J. Stampfer, Dong D. Wang. Coffee and Tea Intake and Cognitive Function. JAMA, 2026; 335 (11): 961 DOI: 10.1001/jama.2025.27259