Drinking 2–3 cups of coffee a day linked to dramatically lower dementia risk

Drinking 2–3 cups of coffee a day linked to dramatically lower dementia risk

- Date:

- November 7, 2026

- Source:

- American Physiological Society

- Summary:

- Drinking two to three cups of caffeinated coffee daily was linked to a dramatically lower risk of dementia and better cognitive functioning in a study spanning up to 43 years. The benefits appeared regardless of genetic risk, but decaffeinated coffee did not show the same association.

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Your daily cup of coffee may be doing more than helping you wake up in the morning. A long-running study of U.S. adults suggests that drinking caffeinated coffee regularly is associated with a substantially lower risk of dementia and better cognitive health as people age.

Researchers found that adults who consumed higher amounts of caffeinated coffee developed dementia at considerably lower rates than those who rarely or never drank it. The findings were based on follow-up periods extending as long as 43 years, offering a valuable look at how everyday drinking habits relate to brain health over time.

The strongest associations appeared among people who drank two to three cups of caffeinated coffee each day. Tea consumption was also linked to better cognitive outcomes, although the amount associated with the greatest benefit was somewhat lower.

Interestingly, decaffeinated coffee did not show the same benefits, raising questions about whether caffeine itself might help explain the connection.

Coffee Drinkers Showed Much Lower Dementia Rates

One of the most striking findings involved the difference in dementia rates between regular coffee drinkers and people who consumed little or no coffee.

Among U.S. adults who drank higher amounts of caffeinated coffee, researchers recorded 141 dementia cases annually for every 100,000 people. In comparison, the rate was 330 cases per 100,000 people each year among those who rarely or never drank caffeinated coffee.

Dementia is a general term for conditions that progressively interfere with memory, thinking, reasoning, and the ability to perform everyday activities. Alzheimer's disease is its most common cause, although several other brain disorders can also lead to dementia.

While occasional forgetfulness can be a normal part of aging, dementia involves cognitive difficulties severe enough to disrupt daily life. Identifying lifestyle habits associated with lower dementia risk is therefore an important area of research, particularly as populations grow older.

The findings suggest that regular caffeinated coffee consumption may be one such habit. However, the results show an association rather than proving that coffee directly prevents dementia. Other differences between coffee drinkers and people who avoid coffee could also contribute to the observed results.

Coffee Was Also Linked to Better Cognitive Health

The potential benefits were not limited to diagnosed dementia. Participants who drank more caffeinated coffee were also less likely to report that their memory or thinking abilities had declined.

Researchers found that 7.8% of adults who consumed higher amounts of caffeinated coffee reported subjective cognitive decline, compared with 9.5% of those who rarely or never drank it.

Subjective cognitive decline refers to changes in memory or thinking that people notice themselves, even when those difficulties have not necessarily been confirmed by formal cognitive testing. Someone experiencing it might feel that remembering information, concentrating, or finding the right words has become more difficult.

Such complaints do not automatically indicate dementia. Nevertheless, they can provide useful information about how people perceive changes in their cognitive abilities as they grow older.

The lower percentage among caffeinated coffee drinkers adds to the evidence linking coffee consumption with healthier cognitive aging.

How Much Coffee Offers the Greatest Benefit?

The researchers also examined whether the amount of coffee consumed was related to the strength of the observed benefits.

Drinking two to three cups of caffeinated coffee per day was associated with the most favorable outcomes for dementia risk and cognitive functioning.

Notably, this association remained apparent regardless of participants' genetic risk of developing dementia. In other words, the relationship between coffee consumption and brain health was observed even among people whose inherited characteristics might make them more vulnerable to the disease.

Genetic risk refers to the influence of inherited variations in DNA that can increase or decrease a person's likelihood of developing certain conditions. Although genetics can play an important role in dementia, they are only one part of a much larger picture that includes age, general health, and lifestyle.

The results also suggest that drinking larger amounts of coffee is not necessarily better. Consumption beyond the range associated with the strongest benefits did not appear to provide additional protection.

Tea Drinkers May Benefit Too, but Decaf Was Different

Coffee was not the only beverage associated with better brain health. Researchers found that drinking tea was also linked to lower dementia risk and better cognitive functioning.

For tea, the strongest associations appeared among participants who consumed one to two cups per day. As with coffee, drinking more than this amount did not appear to produce further benefits.

However, the study did not distinguish between caffeinated and noncaffeinated tea. As a result, the findings cannot establish whether caffeine was responsible for the association observed among tea drinkers.

The results for coffee offered an additional clue. While regular caffeinated coffee was associated with lower dementia risk and better cognitive outcomes, decaffeinated coffee did not demonstrate the same benefits.

Caffeine is a naturally occurring stimulant found in coffee, tea, and several other plants. It acts on the central nervous system and is best known for temporarily increasing alertness and reducing feelings of tiredness.

Whether caffeine also contributes to better brain health over many years is a separate question. The difference between regular and decaffeinated coffee makes this possibility worth investigating, but it does not establish caffeine as the cause of the observed benefits.

Taken together, the findings suggest that moderate consumption of caffeinated coffee and tea may be associated with healthier brain aging. For coffee drinkers, two to three cups daily appeared to offer the strongest association, while one to two cups of tea showed the most favorable results among tea drinkers.

Although additional research is needed to determine whether these beverages directly influence dementia risk, the long-term findings offer encouraging news for people who already enjoy coffee or tea as part of their daily routine.

Story Source:

Materials provided by American Physiological Society. Original written by Tori DeAngelis. Note: Content may be edited for style and length.

Journal Reference:

- 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, Dementia Risk, and Cognitive Function. JAMA, 2026; 335 (11): 961 DOI: 10.1001/jama.2025.27259

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