Chinese scientists have found that coffee and tea consumption reduces the risk of stroke and dementia 
Researchers from China have shown that moderate consumption of coffee and/or tea is associated with a lower risk of stroke and dementia. An article by scientists dedicated to the benefits of coffee and tea was published in the journal PLOS Medicine.
Experts from Tianjin Medical University observed more than 365 thousand participants in the UK Biobank study aged 50 to 74 years. Scientists tracked their health data from 2006-2010, when people signed up for the study, to 2020. The study participants reported their tea and coffee consumption themselves. During the observation period, more than five thousand people developed dementia, more than ten thousand suffered at least one stroke.
It turned out that the lowest risk of stroke and dementia was in those people who drank two or three cups of coffee or three to five cups of tea a day, or four to six cups of coffee and tea a day. Those who drank two to three cups of coffee and two to three cups of tea a day had a 32 percent lower risk of stroke and 28 percent lower risk of dementia. Both coffee and tea consumption were also associated with a lower risk of developing dementia after stroke, ischemic stroke, and vascular dementia.
While there is a possibility that coffee and tea consumption may have protective effects, it is impossible to deduce a causal relationship from the association identified in the work, the researchers warn. In addition, they note, UK Biobank members represent a relatively healthy sample compared to the general population.