Tea Drinkers Show 11% Lower Vascular Disease Risk in 486,000-Person Study

Does the type of tea matter?

It appears to. Black tea showed more consistent associations with reduced vascular disease risk than green tea, suggesting that different varieties may not have identical relationships with cardiovascular health.

Both come from the same plant, Camellia sinensis, but they undergo different processing methods. Black tea is allowed extensive oxidation, a chemical process that changes the composition of compounds in the leaves, while green tea is processed to limit oxidation.

Tea naturally contains plant compounds called polyphenols, which have drawn scientific interest for their antioxidant properties, meaning they can help limit certain types of cellular damage caused by reactive molecules, and their potential effects on blood vessel function. The study does not establish whether these compounds explain the observed differences between the two varieties.

Strength mattered as well. Participants who drank tea of moderate strength had the lowest associated vascular disease risk, indicating that stronger brews were not necessarily linked to greater benefit.

Why does temperature change the picture?

The temperature finding is the study's most striking reversal. Although regular tea consumption was generally associated with reduced vascular disease risk, tea consumed at extremely high temperatures appeared to have the opposite association.

Very hot beverages can expose tissues in the mouth and digestive tract to high temperatures, but the study did not establish the biological mechanism behind the observed vascular risk. It also did not identify a specific temperature at which tea becomes harmful. The findings should therefore not be read as proof that extremely hot tea directly causes vascular disease. They do raise the question of whether certain drinking habits could offset some of the favorable associations seen with regular consumption.

How do lifestyle factors interact with tea?

The researchers examined tea drinking alongside smoking and physical activity. Their analysis showed that people who regularly drank tea, were not current smokers and maintained high levels of physical activity had the lowest vascular disease risk of any group studied.

"Joint analyses showed that tea consumption, smoking status and physical activity were collectively associated with vascular risk, with the favorable combination of habitual tea consumption, non-current smoking and high physical activity associated with the lowest risk," the authors wrote.

This result underscores a broader point. Regular physical activity supports cardiovascular health by improving circulation, helping regulate blood pressure and supporting the function of the heart and blood vessels. Avoiding smoking reduces exposure to substances that can damage blood vessels. Tea drinking, in other words, may be one component of a wider pattern of habits rather than a standalone safeguard.

What are the study's limits?

Three caveats shape how the findings should be read. First, the observational design cannot prove cause and effect. Second, the study population was Chinese, and tea drinking habits there may differ from those elsewhere. Third, the mechanism behind the temperature association remains unexplained, and no harmful temperature threshold was identified.

Even with those limitations, the study offers encouraging evidence that a widely consumed beverage is associated with cardiovascular health across a very large population over nearly a decade. More research will be needed to determine whether tea consumption directly influences disease risk.

For now, the evidence suggests a simple calculus: the amount, the variety, the strength and, above all, the patience to let the cup cool.