A recent large-scale study suggests that enjoying 2 to 3 cups of caffeinated coffee per day—or about 1 to 2 cups of caffeinated tea—may be linked to a lower risk of developing dementia and slower cognitive decline over time. The research, which tracked more than 130,000 adults for up to 43 years, found that people with higher intake of caffeinated coffee had roughly an 18% lower risk of dementia compared to those who drank little or none. For tea, the reduction was around 14–15%.
The benefits appeared strongest at moderate levels: specifically around 2–3 cups of coffee or 1–2 cups of tea daily, with no additional gains beyond that point (and the effects plateaued). Notably, decaffeinated versions of coffee showed no significant association with reduced dementia risk, pointing to caffeine or related bioactive compounds as potential key factors. Researchers suspect these may help by reducing neuroinflammation, supporting better vascular function, and improving insulin sensitivity (which could indirectly protect against diabetes-related dementia risks).
The study involved long-term follow-up, with participants generally maintaining consistent coffee and tea habits over decades. Benefits were more pronounced in those under 75, suggesting that building these habits earlier in life could be particularly helpful. Out of the group, about 11,000 cases of dementia developed during the observation period.
However, experts stress important caveats: This is an observational study, so it shows associations rather than proving cause and effect. Other healthy lifestyle factors (like diet, exercise, or overall habits) might contribute to the outcomes. Self-reported intake data can also introduce some bias.
Nutritionist Lauren Manaker, MS, RDN, noted: “While the results suggest that moderate consumption of caffeinated coffee (2-3 cups/day) and tea (1-2 cups/day) may be associated with a lower risk of dementia and modestly better cognitive function, there are several factors to consider.” She highlighted that people sensitive to caffeine might experience side effects like anxiety, insomnia, or increased heart rate, which could outweigh any upsides. Adding lots of sugar, syrups, or heavy creamers could also diminish potential benefits.
In summary, moderate caffeinated coffee or tea appears promising as part of a brain-healthy routine, but it should complement—not replace—a balanced diet full of whole foods, fruits, vegetables, and healthy fats. If you’re considering changes to your caffeine habits, especially with any health conditions, talk to your doctor first.
Author Attribution
This rewritten summary is based on the original AOL article “New Study Finds Drinking 3 Cups Of Coffee A Day Could Lower Dementia Risk—But There’s A Catch,” published February 10, 2026. The piece draws from a large prospective cohort study published in JAMA (doi:10.1001/jama.2025.27259), with insights from nutritionist Lauren Manaker, MS, RDN.
