A study followed nearly 500,000 people in China for an average of nine years, recording their tea consumption and illnesses. Drinking tea at least three times a week was associated with an 11.2% lower overall risk of vascular disease, which affects blood vessels. The strongest link was with ischaemic stroke, caused by blocked blood flow to the brain: its risk was 36.6% lower.
The median amount consumed—the middle value among participants—was between two and three cups daily. However, the lowest risk was associated with six to eight cups a day. Black tea showed the strongest and most consistent association, followed by green tea. Moderately strong tea that was not burning hot produced the most favourable results. In contrast, burning hot tea was linked to a 16% increase in vascular disease risk.
Natural compounds in tea may protect the lining of blood vessels and support healthy circulation. Nevertheless, the researchers warn that tea alone cannot protect against cardiovascular disease and should accompany a healthy lifestyle and established prevention measures. Dell Stanford, a British Heart Foundation dietitian who was not involved in the research, stressed that this was an observational study. Because researchers observed people's habits rather than testing a treatment, differences in diet and lifestyle could help explain the findings. The results therefore do not prove that drinking tea protects the heart.
