Key Points of the Study Related to Dementia Risk and Caffeine:
Higher intake of caffeinated coffee was associated with an 18% lower risk of dementia.
Tea drinkers showed about a 14-15% lower risk compared to low or non-drinkers.
The strongest association was seen with 2-3 cups of caffeinated coffee per day or 1–2 cups of tea per day.
There was no significant association between decaffeinated coffee intake and reduced dementia risk.
A groundbreaking study published in the Journal of the American Medical Association (JAMA) on February 11, 2026, has found that people who regularly drink caffeinated coffee or tea may have a significantly lower risk of developing dementia later in life.
Researchers found that people who regularly consumed moderate amounts of caffeinated coffee or tea in midlife had a significantly lower risk of developing dementia compared to those who avoided these drinks.
See also: Changes in Circadian Rhythms Linked to Higher Dementia Risk
The study tracked over 131,821 people for up to 43 years. This makes it one of the most comprehensive studies on the relationship between caffeine consumption and brain health.
The results were striking:
Coffee drinkers, including both males and females, who consumed 2–3 cups of caffeinated coffee daily had an 18% lower risk of developing dementia compared to those who drank little or no coffee.
Tea drinkers who had 1–2 cups of caffeinated tea per day showed a 14–15% lower risk of dementia.
Participants who drank caffeinated coffee also experienced less cognitive decline.
“Our study alone can’t prove causality, but to our knowledge, it is the best evidence to date looking at coffee and tea intake and cognitive health,” said lead researcher Yu Zhang from Harvard University to The Guardian.
One of the study’s most important findings was the difference between caffeinated and decaffeinated coffee. Researchers found no significant link between decaffeinated coffee consumption and reduced dementia risk. In other words, decaffeinated coffee showed no significant association with dementia risk.
See also: Study Finds Blood Pressure Control Can Offset Genetic Dementia Risk
The research revealed a “sweet spot” for consumption:
Coffee: 2–3 cups per day showed the most benefit.
Tea: 1–2 cups per day appeared optimal.
Moderate intake showed the strongest association with lower dementia risk.
The study actually suggests the opposite, moderate caffeine intake is associated with better cognitive function and less memory decline. However, the researchers emphasize that more isn’t necessarily better, and caffeine consumption should remain moderate.
The study concluded:
"Greater consumption of caffeinated coffee and tea was associated with a lower risk of dementia and modestly better cognitive function, with the most pronounced association seen at moderate intake levels."
According to the World Health Organization (WHO), dementia is a term used to describe several diseases that affect memory, thinking, and the ability to perform daily activities. It is not a single disease but a syndrome caused by various underlying conditions that damage the brain over time.
In 2021, an estimated 57 million people were living with dementia worldwide, with more than 60% residing in low- and middle-income countries. Each year, nearly 10 million new cases are diagnosed globally.
Reference:
1. Zhang Y, Liu Y, Li Y, et al. Coffee and Tea Intake, Dementia Risk, and Cognitive Function. JAMA. Published online February 09, 2026. doi:10.1001/jama.2025.27259
