Drinking coffee, tea may lower risk of dementia: Study
What's the story
A recent study has found that drinking two to three cups of caffeinated coffee or one to two cups of caffeinated tea daily could lower the risk of dementia by 15-20%. The research, published in the Journal of the American Medical Association, analyzed health records over a period of 40 years for more than 130,000 people. The findings suggest that habitual consumption of these beverages may be beneficial for cognitive health.
Cognitive benefits
Caffeine and cognitive performance
The study also found that those who consumed caffeinated coffee reported a slightly less cognitive decline than their decaffeinated counterparts. They also performed better on certain objective tests of brain function. However, it's important to note that while these findings suggest a link between caffeine consumption and improved cognitive performance, they do not prove causation. Other factors could be at play in this relationship.
Protective properties
How could caffeine help?
The lead author of the study, Yu Zhang from Harvard University, noted that coffee and tea contain caffeine and polyphenols which could protect against brain aging. These substances may improve vascular health and reduce inflammation and oxidative stress. Zhang also said that while their study cannot prove causality, it is the best evidence to date looking at coffee and tea intake with cognitive health.
Future studies
Need for more research
While the study shows a link between caffeine consumption and reduced risk of dementia, further research is required to confirm whether these drinks actually protect the brain. Randomized trials assigning people to drink caffeinated or decaffeinated drinks for decades are largely impractical. However, future studies could look at whether these drinks drive biological changes linked with brain function that could be detected in scans or other tests.
Mixed impact
Caffeine's dual effects
Naveed Sattar, a Professor of cardiometabolic medicine at the University of Glasgow, said that caffeine can have both positive and negative effects on the brain. While tea and coffee contain antioxidants that may be beneficial, caffeine can also raise blood pressure in some people. This is a major risk factor for dementia. "Caffeine does a multitude of things, some which may be beneficial, some which may be harmful," Sattar said.
Holistic approach
Coffee, tea not 'magic bullet' for brain health
Zhang emphasized that coffee or tea shouldn't be seen as a magic bullet for brain health. He stressed the importance of maintaining a healthy lifestyle, regular exercise, balanced diet and good sleep for better brain health. This is in line with research suggesting that addressing factors like obesity, smoking, excess alcohol consumption, hearing loss and high blood pressure could prevent or delay about half of dementia cases globally.