Study analyzed more than 130 thousand people. But… “We are not recommending that people who don’t drink coffee start drinking it.”
Moderate daily consumption of caffeinated coffee or tea may be associated with a lower risk of dementia and to one slower cognitive decline.
The analyzed data from more than 130,000 people followed over several decades in the USA.
Between 1980 and 2023, participants regularly answered dietary questionnaires and underwent cognitive assessments, allowing consumption habits, dementia diagnoses and changes in brain performance to be monitored.
The results indicate that people who habitually consumed two to three cups of coffee or caffeinated tea per day had a 15 to 20% lower risk of developing dementiacompared to those who did not consume these drinks. This group also showed slightly less cognitive decline and better performance on some objective tests of brain function.
According to Yu Zhang, a researcher at Mass General Brigham, the data should be interpreted with caution. “We are not recommending that people who don’t drink coffee start drinking“, he told . “For those who already consume, the results are reassuring”, he added.
The study itself recognizes that it is not possible to establish a cause and effect relationship, since other factors lifestyle habits can influence the risk of dementia.
Among the possible explanations for the observed association are the effects of caffeine and of polyphenols present in coffee and tea, which can contribute to reducing inflammation, oxidative stress and improving vascular and metabolic health. Caffeine, for example, is associated with lower rates of type 2 diabetes, a known risk factor for dementia.
After around 37 years of follow-up, only 11,000 participants were diagnosed with dementia, with the association being strongest in people aged 75 and under.
The risk was 18% lower among caffeinated coffee drinkers and 14% lower among frequent tea drinkers.
Os Effects stabilized with two to three cups of coffee or one to two of tea per day.
Despite the promising results, researchers point out several limitations, such as the lack of distinction between types of tea, coffee preparation methods or the addition of sugar and milk.
Zhang emphasizes that dementia is a complex condition and reinforces: “Coffee, in itself, is not a magic shield”.
A healthy lifestyle, with exercise, a balanced diet and good sleep, continues to be essential for brain health.
