Coffee and tea intake linked to reduced rates of stroke and dementia

Drinking coffee and tea may lower the risk of stroke, dementia, and post-stroke dementia, according to a study of healthy individuals aged 50-74, published in the journal PLOS Medicine.

The study was led by Yuan Zhang from Tianjin Medical University in China. There were 365,682 participants recruited from the U.K. Biobank in 2006 and 2010. They were all tracked until 2020. Over the years, subjects self-reported their coffee and tea intake. By the end of the study, 5,079 participants were diagnosed with dementia and 10,053 experienced at least one stroke.

Individuals who drank more coffee and tea, two to three cups of coffee, three to five cups of tea, or four to six cups of coffee and tea a day, had the lowest incidence of stroke and dementia. Compared with participants who drank neither coffee nor tea, subjects who drank two to three cups of coffee, and two to three cups of tea daily were 32 percent less likely to experience a stroke and 28 percent less likely to experience dementia. Drinking coffee alone, or in addition to tea, was also linked to a decreased risk of post-stroke dementia.

The sample from the U.K. Biobank included relatively healthy people, making it difficult to apply this study to the general population. In addition, a small percentage of the participants experienced stroke or dementia. In turn, the sample size was too small to make any broad conclusions. Finally, researchers said they cannot infer that coffee and tea intake prevents stroke, dementia, or post-stroke dementia altogether, even though there may be a relation between them.