Drinking tea and coffee every day could lower the risk of developing a stroke by almost a third, according to the largest study of its kind.
The research followed 365,000 people aged between 50 and 74 for more than a decade.
The participants self-reported their tea and coffee consumption at the start of the UK Biobank study, the results of which were published in the journal PLOS Medicine.
Over the course of the study, 5,079 participants developed dementia and 10,053 experienced at least one stroke.
The researchers found that those two drank 2-3 cups of coffee or 3-5 cups of tea per day, or a combination of 4–6 cups of coffee and tea had the lowest incidence of stroke or dementia.
Meanwhile, participants who drank 2-3 cups of coffee and 2-3 cups of tea each day had a 32 per cent lower risk of stroke and 28 per cent lower risk of dementia than those who drank neither tea nor coffee.
Consumption of either coffee alone or coffee alongside tea was also associated with a lower risk of post-stroke dementia.
The authors wrote: “Our findings suggested that moderate consumption of coffee and tea separately or in combination were associated with lower risk of stroke and dementia.”
However, the authors cautioned that the UK Biobank reflects a relatively healthy sample of the population.
While it’s possible that the drinks may protect against the conditions, causality cannot be confirmed from the data.
Prof Kevin McConway, an emeritus professor of applied statistics at the Open University, added:
[W]hat generally happened is that the risk of stroke or dementia was lower in people who drank reasonably small amounts of coffee or tea compared to those who drank none at all, but that after a certain level of consumption, the risk started to increase again until it became higher than the risk to people who drank none.“Once the coffee consumption got up to seven or eight cups a day, the stroke risk was greater than for people who drank no coffee, and quite a lot higher than for those who drank two or three cups a day.”
