Coffee, Tea, and Your Brain: What a New JAMA Study Means for You

A new study in the journal JAMA suggests that moderate drinking of caffeinated coffee or tea is linked to a lower risk of dementia and slightly better thinking skills over many years. This is encouraging news for many BrainSavers members who already enjoy a morning cup.

What This New Study Asked About Coffee, Tea and Your Brain

Researchers from Harvard’s T.H. Chan School of Public Health and Brigham and Women’s Hospital asked whether long‑term intake of coffee and tea is related to dementia risk and everyday thinking ability.

They wanted to know three main things:

• Does drinking caffeinated coffee lower the chance of developing dementia?

• Does tea have similar effects?

• Is there any benefit from decaffeinated coffee?

What the Researchers Did

The team tracked more than 130,000 male and female health professionals in the United States for up to 43 years. None of these participants had dementia, Parkinson’s disease, or cancer at the start of the study.

Every 2 to 4 years, participants completed detailed food questionnaires, including how many cups of caffeinated coffee, decaf coffee, and tea they consumed. Over time, the researchers:

• Recorded who developed dementia (more than 11,000 people).

• Collected reports of “subjective cognitive decline” – when people felt their memory or thinking was getting worse.

• Gave a subset of older women telephone thinking tests, including a global cognition score and the Telephone Interview for Cognitive Status (TICS).

They also adjusted for multiple other factors that affect brain health, including age, education, smoking, exercise, diet quality, blood pressure, diabetes, and cholesterol.

What They Found About Coffee and Tea

The main message: moderate intake of caffeinated coffee or tea was linked to lower dementia risk and slightly better cognitive scores, but more was not necessarily better.

Key Findings:

• People who drank more caffeinated coffee had fewer cases of dementia than those who drank little or none.

• The lowest risk showed up around 2 to 3 cups of caffeinated coffee per day.

• Tea drinkers also had lower dementia risk, with the strongest association at about 1 to 2 cups per day.

• People who drank more caffeinated coffee or tea were less likely to report worrisome memory or thinking problems.

• In women who took telephone thinking tests, higher caffeinated coffee and tea intake was linked to slightly better scores, though the differences were small.

• Just as important:

• Decaffeinated coffee was not associated with a lower risk of dementia or better test scores.

• Very high intakes did not add extra benefit beyond the moderate levels above.

The authors stress that this is an observational study, so it cannot prove that coffee or tea causes better brain outcomes. Other lifestyle or health factors may still play a role, even after adjustment.

You can read the full article, “Coffee and Tea Intake, Dementia Risk, and Cognitive Function,” in JAMA at: https://doi.org/10.1001/jama.2025.27259.

What This Means for BrainSavers Members

For many older adults, this study offers a simple, practical message: if you already tolerate coffee or tea well, moderate caffeinated intake can be part of a brain‑healthy lifestyle. It does not replace exercise, healthy eating, sleep, social connection, medical care, or cognitive training — all central elements of the BrainSavers program.

Here is how I would interpret this for you:

• You do not need to give up your morning coffee or tea for your brain’s sake, unless your doctor has told you to.

• The “sweet spot” in this study was around 2–3 cups of caffeinated coffee per day or 1–2 cups of tea per day, with no extra brain benefit at much higher intakes.

• Decaf coffee did not show the same association, suggesting that caffeine and other compounds in caffeinated coffee and tea may play an important role.

At the same time, the study showed that differences in thinking scores were modest. Coffee and tea may give your brain a small extra nudge, but they are just one piece of your full BrainSavers plan.

Practical Tips for Enjoying Coffee and Tea Safely

If you decide to use this information, here are practical, senior‑friendly guidelines that fit with BrainSavers principles:

1.      Stay in the “moderate” zone

• Aim for up to about 2–3 small cups of caffeinated coffee a day, or 1–2 cups of caffeinated tea, if you tolerate this amount.

• More than that did not clearly improve dementia risk or thinking scores in this study.

2.      Protect your sleep and mood

• Avoid caffeinated drinks late in the day; poor sleep is a strong enemy of brain health.

• If you notice more anxiety, palpitations, or shakiness after caffeine, cut back and talk with your clinician.

3.      Watch your heart, blood pressure, and bones

• If you have heart rhythm problems, high blood pressure, osteoporosis, reflux, or bladder issues, ask your physician what level of caffeine is safe for you.

• Do not make big changes in caffeine intake without checking first if you take certain heart or psychiatric medicines or blood thinners.

4.      Keep the drink brain‑healthy

• Skip or minimize sugar, flavored syrups, and heavy creamers; these can add large amounts of calories and sugar.

• Choose simpler drinks: plain coffee, coffee with a small amount of milk, or unsweetened or lightly sweetened tea.

• Avoid energy drinks; they often contain very high caffeine plus sugar and other stimulants.

5.      If you cannot drink caffeine

• Remember that many other habits have a larger impact on dementia risk: regular physical activity, blood pressure and diabetes control, not smoking, a Mediterranean‑style eating pattern, social engagement, and structured brain exercises.

• Herbal teas and water can still be part of your daily rituals while you focus on these higher‑impact brain‑healthy behaviors.

As I tell my BrainSavers members: enjoy your coffee or tea if it suits you, but let it support—not replace—your full brain‑healthy lifestyle. This new research gives us one more reason to savor that morning cup as we keep moving, thinking, and connecting to protect our brains over the years.