You probably do not think much about your daily drink routine. But what if the pattern you repeat for years, not days, is the part that matters?
Researchers recently looked at decades of health and diet information to see whether common beverages like coffee and tea might be connected to brain health as people age. The results are not a reason to overhaul your life, but they do add an interesting piece to a bigger conversation about dementia prevention.
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A study that followed people long enough to spot patterns
This research used two well known long-term studies in the United States: the Nurses’ Health Study and the Health Professionals Follow-Up Study. In total, 131,821 participants were tracked for up to 43 years, with repeated check-ins about diet and cognitive outcomes.
Over the follow-up period, 11,033 participants developed dementia. Because the study followed people forward in time (instead of asking them to remember the past), it can capture long-term habits more reliably than shorter studies. Still, it remains an observational study, which means it can spot links but cannot prove that coffee or tea directly prevents dementia.
The amount that showed the clearest link
When researchers compared people by how much caffeinated coffee they drank, a clear pattern showed up:
Those with the highest caffeinated coffee intake had an 18% lower risk of dementia than people who reported little or no caffeinated coffee.
People who drank caffeinated coffee also reported fewer memory or thinking concerns, called subjective cognitive decline (7.8% vs 9.5%).
On some objective cognitive tests, caffeinated coffee drinkers performed a bit better overall.
The strongest links appeared at what many people would consider moderate intake: about 2 to 3 cups of caffeinated coffee per day. Tea showed a similar pattern, with the clearest links at about 1 to 2 cups per day.
One important nuance: the researchers described the overall effect as small. So even if the link is real, it would likely be a modest contributor alongside other factors like exercise, blood pressure control, sleep, and not smoking.
Interesting article: How much coffee is too much coffee? - (Universal-Sci)
Decaf, genetics, and other questions the study tried to answer
A detail many people will ask about right away: decaf did not show the same association. That does not prove caffeine is the only factor, but it does suggest caffeine may play a meaningful role, possibly alongside other compounds found in coffee and tea (like polyphenols).
The team also looked at whether genetic risk changed the pattern. The association was similar across different levels of genetic predisposition, suggesting the observed link was not limited to people at lower inherited risk.
If you are interested in more details about the underlying research, be sure to check out the paper published in the peer-reviewed journal JAMA, listed below.
Sources, further reading and more interesting articles:
Coffee and tea intake, dementia risk, and cognitive function - (JAMA)
How much coffee is too much coffee? - (Universal-Sci)
Women Who Drink Coffee Daily May Age Better - Here’s Why - (Universal-Sci)
How to make the perfect cup of coffee – with a little help from science - (Universal-Sci)
Why you like coffee, and I choose tea – it’s in the genes - (Universal-Sci)
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