Drinking coffee or tea is associated with reduced risk for stroke and dementia, with the biggest benefit associated with consuming both beverages, new research suggests.
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Investigators found that individuals who drank two to three cups of coffee and two to three cups of tea per day had a 30% decrease in incidence of stroke and a 28% lower risk for dementia compared with those who did not.
“From a public health perspective, because regular tea and coffee drinkers comprise such a large proportion of the population and because these beverages tend to be consumed habitually throughout adult life, even small potential health benefits or risks associated with tea and coffee intake may have important public health implications,” the investigators wrote.
The study was published online Nov. 16 in PLOS Medicine.
Synergistic effect?
Whereas earlier studies have shown significant health benefits from moderate coffee and tea intake separately, few have examined the effect of drinking both.
Researchers enrolled 365,682 participants from the UK Biobank for the analysis of coffee and tea consumption and stroke and dementia risk and 13,352 participants for the analysis of poststroke dementia.
During a median follow-up of 11.4 years, 2.8% of participants experienced a stroke and 1.4% developed dementia.
After adjustment for confounders, stroke risk was 10% lower in those who drank a half-cup to a cup of coffee per day (P < .001) and 8% lower in those who had more than two cups a day (P = .009). Tea drinkers who had more than two cups a day saw a 16% reduction in stroke (P < .001).
Those who drank both coffee and tea during the day saw the greatest benefit. Drinking two to three cups of coffee and two to three cups of tea lowered stroke risk by 32% (P < .001) and dementia risk by 28% (P = .002).
Drinking both beverages offered significantly greater benefits than drinking just coffee or tea alone, with an 11% lower risk for stroke (P < .001), an 8% lower risk for dementia (P = .001), and 18% lower risk for vascular dementia (P = .001).
Among those participants who experienced a stroke during the follow-up period, drinking two to three cups of coffee was associated with 20% lower risk for poststroke dementia (P = .044), and for those who drank both coffee and tea (half to one cup of coffee and two to three cups of tea per day) the risk for poststroke dementia was lowered by 50% (P =.006).
There was no significant association between coffee and tea consumption and risk for hemorrhagic stroke or Alzheimer’s disease.
The study was funded by the National Natural Science Foundation of China. The authors have disclosed no relevant financial relationships.
A version of this article first appeared on Medscape.com.