A daily cup of coffee or tea halved the risk of dementia and reversed some of the effects of stroke, new research suggests.
The findings, published in the journal Neurology, add to the health benefits associated with an intake of at least four cups of coffee a day, which are thought to include a low-level of antioxidants and boost cerebral blood flow.
Drinking multiple cups a day may also help protect against some cancers and Parkinson’s disease, a study from the Harvard T.H. Chan School of Public Health found in March.
The latest study looked at over 100,000 people over a 20-year period. At the start of the study, the participants, aged between 45 and 74 years, were asked about their daily intake of alcohol, alcohol intake before they reached 35 years old, caffeine intake, coffee and tea consumption, and cholesterol levels. These were then followed up after 10 years and again after the participants became demented.
An annual average of 20 cups of coffee was associated with a 50% lower risk of dementia or dementia related disorders and a 17% lower risk of stroke compared with abstainers. A single cup of tea was linked to a 19% reduced risk of dementia or dementia related disorders.
The results were accompanied by some caution, as the results were simply a correlation, not a direct cause-and-effect. Dr Sara Bleich, director of the San Francisco VA Health Care System’s Alzheimer’s Disease Research Center, told NPR: “Although this study suggests,” she continued, “there is a protective effect of certain types of coffee and tea, we need more research in order to know precisely what coffee and tea are protective against, and what harms may be associated with them.”
In April, a review published in the journal Brain found that those who consume more than one or two cups of coffee a day have a lower risk of Alzheimer’s disease, while the benefits seem to be amplified when coffee is added to a strong tea. A study from the department of nutrition and dietetics at Ohio State University recently found that a daily cup of coffee is linked to a 30% lower risk of dying from cardiovascular disease.