Share on PinterestA new study links caffeinated coffee to a reduced risk of dementia. DIEGO ARENAS/Stocksy
- Past studies show that eating a healthy diet and consuming foods and beverages with certain naturally-occurring substances — such as caffeine — may help lower a person’s dementia risk.
- Some of these substances include flavonoids, antioxidants, and vitamins.
- A new study found that moderate consumption of caffeinated coffee or tea, which is high in antioxidants, helped reduce dementia risk, slow cognitive decline, and preserve cognitive function.
According to the World Health Organization (WHO), an estimated 57 million people globally were living with dementia in 2021.
While the cause of dementia is still not entirely clear, previous research shows there are a number of ways people may be able to lower their dementia risk by following certain healthy lifestyle choices. These include not smoking, getting enough sleep, reducing stress, being physically active, and eating a healthy diet.
When it comes to diet, past studies show that certain nutrients and other naturally occurring substances in food can possibly impact a person’s dementia risk. These include flavonoids, antioxidants, vitamins E and B, and healthy fats.
Researchers have also been looking at another ingredient naturally found in some foods — caffeine — and how it might impact a person’s dementia risk. For example, a study published in May 2024 found that moderate coffee or tea consumption helped reduce the risk of cognitive disorders, and a study published in May 2025 reported that greater caffeine intake, including caffeinated coffee and tea, was associated with a lower risk of dementia and better cognitive function.
A new study, recently published in JAMA, adds to what we know about caffeine and dementia risk, finding that moderate consumption of caffeinated coffee or tea helps reduce dementia risk, slow cognitive decline, and preserve cognitive function.
Highest intake of caffeinated coffee, tea linked to lower dementia risk
For this study, researchers analyzed health data from more than 131,000 participants of the Nurses’ Health Study (NHS) and Health Professionals Follow-Up Study (HPFS). Study participants provided information on their diet, completed assessments of dementia, cognitive decline, and objective cognitive function, and were followed up for up to 43 years.
At the study’s conclusion, researchers found that both male and female participants who consumed the most caffeinated coffee had an 18% lower risk of dementia than those with little to no caffeinated coffee consumption.
These high-level caffeinated coffee drinkers also had a lower frequency of developing subjective cognitive decline and better performance on tests of overall cognitive function than participants with little to no caffeinated coffee consumption.
Researchers reported that these results were similar among participants with higher caffeinated tea intake.
In general, scientists found that the cognitive benefits of caffeinated beverages were most seen in study participants who indulged in two to three cups of caffeinated coffee or one to two cups of caffeinated tea each day.
“When searching for possible dementia prevention tools, we thought something as prevalent as coffee may be a promising dietary intervention — and our unique access to high quality data through studies that has been going on for more than 40 years allowed us to follow through on that idea,” Daniel Wang, MD, ScD, associate scientist with the Channing Division of Network Medicine in the Mass General Brigham Department of Medicine, assistant professor at Harvard Medical School, and senior author of this study, stated in a press release.
‘One piece of the puzzle’
“While our results are encouraging, it’s important to remember that the effect size is small and there are lots of important ways to protect cognitive function as we age. Our study suggests that caffeinated coffee or tea consumption can be one piece of that puzzle.”
— Daniel Wang, MD, ScD
More practical tools for dementia risk intervention needed
MNT spoke with Dung Trinh, MD, an internist and chief medical officer of Healthy Brain Clinic at MemorialCare Medical Group in Irvine, CA — who was not involved in this study — about its findings.
Trinh said his first reaction to reading the study results was that it was a well-done, large, long-term observational study that strengthens the case that moderate caffeinated coffee or tea may be linked to better brain health.
Does coffee prevent dementia?
“It’s encouraging to see a ‘moderation’ pattern rather than ‘more is always better’. At the same time, I’d stress one key point: this doesn’t prove coffee prevents dementia. It shows an association, and that’s useful for generating hypotheses and guiding future trials, but it’s not a prescription for everyone — especially people who don’t tolerate caffeine well.”
— Dung Trinh, MD
“Because dementia risk is influenced by many factors, and no single intervention is likely to be ‘the cure,’ Trinh explained. “We need multiple, practical tools including sleep, cardiovascular health, physical activity, education/cognitive engagement, hearing health, social connection, and potentially nutrition-related factors.”
“I would like to see a randomized control trial testing whether assigning people to moderate caffeinated coffee/tea intake improves cognition over time or validated intermediate markers,” he added.
For people who cannot tolerate caffeine
As not every person can tolerate caffeine or likes to drink coffee or tea, MNT asked Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, for other ways that readers can get these same benefits through their diet to potentially lower their dementia risk and maintain their cognitive health.
Richard said it’s important to remember that no single beverage or nutrient is a “magic bullet” — a broader dietary pattern matters most for the brain and overall health.
For those living caffeine-free
“Caffeine may be part of the story, but the antioxidants and plant compounds in coffee and tea are likely doing a lot of the heavy lifting. If someone needs, or prefers, to avoid caffeine, there are other nutrition-focused strategies supported by research that can support cognitive health.”
— Monique Richard, MS, RDN, LDN
These additional strategies include:
- Consume flavonoid-rich foods: “A growing body of evidence links diets rich in berries, leafy greens, nuts, whole grains, and colorful vegetables — all high in antioxidants and anti-inflammatory compounds — with lower risk of cognitive decline,” Richard said.
- Drink herbal teas, where most are naturally caffeine-free: “While some benefits may be tied to caffeine, tea also contains polyphenols and antioxidants that can support overall health even when decaffeinated,” she explained.
- Get enough omega-3 fatty acids: “Long-chain EPA and DHA (from fatty fish, seaweeds, microalgae, or supplements) are associated with brain health and may support membrane integrity and anti-inflammatory processes,” Richard detailed.
- Follow a healthy eating pattern: “It’s not just about what’s in your cup, but the quality and patterns around it,” she explained. “Mediterranean-style or other plant-forward diets that emphasize whole foods, lean proteins, and minimal ultra-processed foods have been frequently associated with lower cognitive decline in observational studies.”
“We’re also learning about the benefits of supporting mitochondrial health, the role of senolytic cells, and how addressing those with functional foods, activity, sleep, and other modalities may influence cognitive health,” Richard added. “Brain health is built over decades, not days, and nutrition is one of the most accessible tools we have.”
