Coffee and tea may boost cognitive health and reduce the risk of dementia, study finds

A study has found that moderate coffee intake — two to three cups daily — may reduce dementia risk, slow down cognitive decline, and preserve cognitive abilities. 

Treatments for dementia are limited, and therefore taking preventative steps is crucial, say the researchers. The study had a follow-up of up to 43 years and demonstrates that daily coffee consumption could have long-term protective benefits for the brain.

“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 have been going on for more than 40 years allowed us to follow through on that idea,” says senior author Daniel Wang, M.D., Sc.D., an associate scientist with the Channing Division of Network Medicine at Mass General Brigham, US.

“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.”

Wang is also an assistant professor in the Department of Nutrition at Harvard Chan School, at Harvard Medical School, and an associate member at the Broad Institute, US.

Highlighting caffeine

The study, published in JAMA, included 131,822 participants, of whom 11,033 developed dementia over the course of the study.

The coffee-consuming participants had an 18% lower risk of developing dementia compared to those who rarely, or did not, drink coffee. They also reported a lower rate of cognitive decline — 7.8% rather than 9.5% — and showed better performance on cognitive tests compared to the non-coffee-drinking group.

Tea drinkers showed similar results as the coffee drinkers, and decaf coffee did not show these effects. The researchers say this suggests caffeine as a main part of the brain-related benefits.

Recent studies have also linked coffee consumption to multiple health benefits.High caffeine intake did not show any harm. Instead, those who drank two to three cups of coffee per day, or one to two cups of tea, showed the highest results.

“We also compared people with different genetic predispositions to developing dementia and saw the same results — meaning coffee or caffeine is likely equally beneficial for people with high and low genetic risk of developing dementia,” comments lead author Yu Zhang, Ph.D. student at Harvard Chan School and a research trainee at Mass General Brigham.

“Greater consumption of caffeinated coffee and tea was associated with lower risk of dementia and modestly better cognitive function, with the most pronounced association at moderate intake levels,” concludes the study.

From brain to gut

Recent studies have also linked coffee consumption to multiple health benefits.

A prior study published in the British Medical Journal found that three to four cups of coffee a day may slow biological aging for those with severe mental illness. The key factor behind this effect is the lengthening of telomeres, a benchmark of cellular aging. The authors suggested this daily habit may offer coffee drinkers the equivalent of five extra biological years, compared to those who do not drink coffee.

Another study demonstrated the effects of paraxanthine — the main metabolite of caffeine — in enhancing memory and neuroplasticity. In another study, it has also been shown to lower the risk of cardiovascular disease.

The beverage also supports gut health, as a previous study revealed a positive link between coffee and gut bacteria, particularly Lawsonibacter asaccharolyticus. This bacterium boosts the metabolization of quinic acid and trigonelline, which research links to a wide range of health benefits.

Coffee is also being explored in functional beverages. Bulletproof recently launched its Coffee + Creatine, a “first of its kind” functional coffee innovation featuring creatine. It is an instant black coffee with toxin-tested 100% Arabica beans. Each cup offers 5 g of creatine monohydrate and 250 mg of electrolytes to support performance and hydration.