Alzheimer’s disease, the leading cause of dementia worldwide, casts a long shadow over aging populations. Characterized by memory loss, cognitive decline, and a progressive inability to manage daily activities, this incurable condition primarily affects those over 65. The search for effective prevention strategies has never been more urgent, especially as the number of people living with Alzheimer’s is expected to surge dramatically in the coming years.
According to GlobalData epidemiologists, the total number of Alzheimer’s cases in eight major markets—including the United States, France, Germany, Italy, Spain, the United Kingdom, Japan, and China—is forecast to leap from 17.4 million in 2026 to a staggering 22.5 million by 2033. That’s a sobering projection, underscoring the pressing need for new approaches to stem the tide of this devastating disease.
One area that’s been brewing up hope—and a fair bit of debate—is the potential role of coffee and tea in preventing Alzheimer’s. For years, scientists have explored whether the caffeine and other compounds found in these everyday beverages might offer some protection against cognitive decline. The evidence, however, has often been inconsistent, leaving both researchers and the public unsure about whether to fill their cups more enthusiastically.
But a major new study, published in February 2026 in The Journal of the American Medical Association, is stirring the conversation once again. Led by Yu Zhang and colleagues, the research examined the links between caffeinated coffee and tea consumption and the risk of developing Alzheimer’s, as well as overall cognitive function. Drawing on robust data from two large, long-running U.S. cohort studies—the Nurses’ Health Study (NHS) and the Health Professionals Follow-up Study (HPFS)—the team analyzed information from a combined pool of 131,821 participants. That’s no small feat, and it gives the findings considerable weight.
Participants in both cohorts were carefully selected: anyone with a history of Parkinson’s disease, dementia, or cancer, or with missing data on caffeinated beverage intake, was excluded. Caffeine consumption was assessed using detailed food frequency questionnaires, while Alzheimer’s cases were identified via death records and self-reported physician diagnoses. Cognitive decline was measured through standardized questionnaires, and the data were pooled for a comprehensive analysis.
So, what did the researchers find? Well, the results are enough to make any coffee or tea lover take notice. According to the study, those with the highest caffeinated coffee intake—4.5 cups a day in the NHS and 2.5 cups in the HPFS—had an 18% lower hazard ratio for Alzheimer’s risk compared to participants who drank no coffee at all. Not only that, but these high-consumption participants also showed a 1.7% lower prevalence of subjective cognitive decline.
Tea drinkers also saw benefits. The highest intake group—defined as one cup per day in the NHS and 0.79 cups in the HPFS—had a 14% lower hazard ratio for Alzheimer’s risk than those who didn’t drink tea. While the numbers may seem modest, they’re statistically significant and suggest that regular consumption of caffeinated coffee and tea could be linked to a reduced risk of developing Alzheimer’s disease.
How might these beverages work their magic? The study offers a couple of plausible biological explanations. First, caffeine itself may lower levels of inflammatory cytokines in the brain, helping to mitigate neuroinflammation—a process increasingly implicated in Alzheimer’s development. Second, coffee and tea are rich in antioxidative compounds (beyond just caffeine) that could help protect brain cells from oxidative stress and damage.
“These findings highlight the role coffee and tea can play in disease development, independent of genetic risk factors,” the study’s authors noted. Still, they were quick to add a note of caution: more research is needed to establish a clear causal pathway. In other words, while the association is compelling, it’s not yet certain that drinking more coffee or tea directly prevents Alzheimer’s.
The research has certainly perked up interest in the scientific community—and in the media. Leana S. Wen, writing in her February 18, 2026 op-ed for The Washington Post, described the idea of drinking coffee to prevent dementia as “not so far-fetched.” She pointed to the study’s robust design and large sample size as reasons to take its findings seriously.
But not everyone is ready to pour another cup just yet. In an opinion piece published on February 23, 2026, a clinical epidemiologist specializing in dementia interventions weighed in on the debate. While acknowledging that the study was “well conducted,” the expert cautioned, “I believe it is premature to promote coffee for the prevention of dementia.” The concern, echoed by many in the field, is that observational studies—even large, carefully designed ones—can’t fully rule out confounding factors. People who drink more coffee or tea, for example, might also have other healthy habits or lifestyle factors that contribute to their lower risk.
That’s not to say the findings aren’t important. In fact, they add to a growing body of evidence suggesting that dietary and lifestyle choices could play a role in reducing the risk of Alzheimer’s and other dementias. And with the expected rise in cases over the next decade, even modest preventive effects could have a meaningful impact at the population level.
For now, experts agree that more research is needed—ideally in the form of randomized controlled trials that can better tease out cause and effect. Until then, the advice remains the same: enjoy coffee and tea in moderation as part of a balanced diet, but don’t count on them as a silver bullet against Alzheimer’s.
The conversation about coffee, tea, and dementia is far from over. As new studies emerge and our understanding of Alzheimer’s deepens, the hope is that simple, everyday choices might one day help turn the tide against this relentless disease. For now, the latest research offers a shot of optimism—but also a reminder to temper enthusiasm with scientific rigor.