Scientists from Tianjin Medical University have found that drinking tea and coffee is linked to lower risks of stroke and dementia.
Coffee and tea are widely consumed beverages known for their health benefits. Most varieties contain caffeine, which can boost mood, metabolism, and overall mental and physical performance.
Both drinks are also rich in antioxidants—compounds that help the body neutralize harmful free radicals that can damage cells and contribute to chronic diseases.
Previous research has linked tea and coffee separately to a reduced risk of type 2 diabetes, heart disease, Parkinson’s disease, stroke, and dementia. However, few studies have examined the combined effects of drinking both beverages.
In this new study, researchers investigated how coffee and tea—alone and in combination—relate to the risks of stroke, dementia, and post-stroke dementia.
The team analyzed data from 365,682 adults aged 50 to 74 who participated in the UK Biobank between 2006 and 2010. Participants’ coffee and tea consumption was assessed at the start of the study, and their health outcomes were tracked for up to 11 years, until 2020.
During the follow-up period:
- 5,079 participants developed dementia
- 10,053 participants experienced a stroke
Key findings
Researchers found that moderate coffee and tea consumption was linked to the lowest risks of stroke and dementia. Specifically:
- 2–3 cups of coffee per day
- 3–5 cups of tea per day
- 4–6 cups of coffee and tea combined per day
Compared with people who drank neither beverage, those who consumed 2–3 cups of coffee and 2–3 cups of tea daily had:
- 32% lower risk of stroke
- 28% lower risk of dementia
The combination of coffee and tea was also associated with reduced risks of ischemic stroke and vascular dementia.
Importantly, drinking both beverages together was linked to a lower risk of post-stroke dementia, with the greatest benefit seen at 3–6 cups per day combined.
The findings indicate that drinking tea or coffee—either separately or together—may help lower the risk of developing stroke and dementia. Coffee alone or combined with tea also appeared to reduce the risk of post-stroke dementia.
One limitation of the study is that coffee and tea intake was self-reported only once, at the beginning of the study. This may not accurately reflect long-term drinking habits.
The research was published in PLOS Medicine and conducted by Yaogang Wang and colleagues.
