For millions of Europeans, tea is more than a drink—it is a daily ritual, from the classic English breakfast to the ceremonial matcha of Japan. Now, a large new study adds to the evidence that this habit may also protect the heart and brain, but with an important caveat: the temperature matters.
Researchers followed nearly 500,000 adults in China for an average of nine years, tracking their tea consumption and any vascular events that occurred. The findings, published in the Journal of Internal Medicine, show that people who drank tea at least three times a week had an 11.2% lower overall risk of vascular disease, including stroke, coronary heart disease, and heart attack. The strongest protective effect was seen for ischaemic stroke, with a 36.6% reduction, followed by cerebrovascular disease at 19.1%.
But the study also revealed a striking paradox: those who preferred their tea scalding hot saw the opposite effect—a 16% increase in vascular disease risk. Very hot beverages have previously been linked to a higher likelihood of oesophageal cancer, and this new research suggests the cardiovascular system may also be vulnerable to thermal injury.
Brewing habits and health outcomes
The protective association varied depending on how the tea was prepared and consumed. Participants who drank between six and eight cups a day had the lowest risk, while the median intake was two to three cups daily. Black tea showed the strongest and most consistent link to reduced vascular disease, followed by green tea. The researchers attribute this to fermentation-derived compounds such as theaflavins, which have anti-inflammatory and lipid-regulating properties.
Temperature and strength also played a role. The optimal combination, the team found, was a moderately strong brew that was not scalding. This suggests that the way tea is prepared—not just the fact of drinking it—can influence its health effects.
All teas come from the same plant, Camellia sinensis, an evergreen shrub native to East Asia. White, green, oolong, black, and pu-erh varieties differ mainly in how much they are oxidised after harvesting. The bioactive compounds in tea, including polyphenols and flavonoids, have antioxidant and anti-inflammatory properties that help preserve the inner lining of blood vessels and maintain healthy circulation.
Not a silver bullet
The protective association was consistent across most demographic groups but was significantly stronger in individuals with obesity, the researchers noted. However, they caution that tea is not a substitute for a healthy lifestyle or established prevention strategies.
“This was an observational study and other differences in people’s diets and lifestyles could help explain the findings,” said Dell Stanford, senior dietitian at the British Heart Foundation, who was not involved in the research. “The results don’t prove that a daily cuppa protects your heart.”
Cardiovascular disease remains the leading cause of illness and death in the European Union, accounting for one in three of all deaths and affecting an estimated 62 million people. While the study was conducted in China, its findings are likely relevant to European populations, where tea consumption is widespread and cardiovascular risk factors are common.
For those who enjoy a hot brew, the takeaway is simple: let it cool slightly before sipping. The health benefits of tea may be best enjoyed at a temperature that doesn’t burn the mouth—or the arteries.
