Tea May Benefit Heart Health — but Drinking It Scalding Hot Could Be Risky

Regular tea consumption has been linked to a lower risk of cardiovascular disease, but new research suggests that drinking it at extremely high temperatures may undermine some of those benefits. A study published in the Journal of Internal Medicine found that people who drank tea at least three days a week had a lower risk of vascular disease, while those who preferred scalding-hot tea faced a higher risk.

The study analyzed data from more than 485,000 Chinese adults aged 30 to 79. Participants reported how often they drank tea, which varieties they preferred, how strongly they brewed it and the temperature at which they usually consumed it. Over an average follow-up period of about nine years, researchers recorded more than 14,800 cases of cardiovascular and vascular disease, including heart attacks, strokes and peripheral artery disease.

Regular tea drinking linked to lower vascular disease risk

According to Dr. Leana Wen, an emergency physician and clinical associate professor at George Washington University, people who drank tea at least three days a week had an approximately 11% lower risk of vascular disease than those who drank it less often. The association remained after researchers accounted for factors such as age, smoking, physical activity, body weight and existing medical conditions.

The study also found that moderate-strength tea was associated with a lower risk. Black tea showed more consistent links to reduced cardiovascular risk across different types of disease, although green tea was also associated with benefits.

Temperature appeared to matter, too. Participants who reported drinking tea at a “burning hot” temperature had a 16% higher risk of vascular disease than those who did not regularly drink tea. By contrast, people who drank tea at room temperature or at a hot but comfortable temperature had a significantly lower risk than non-regular tea drinkers.

However, the findings have important limitations. Participants reported their preferred tea-drinking temperature themselves, rather than having it measured objectively. What one person considers scalding hot may differ from another person's perception. Other lifestyle or dietary differences may also have influenced the results.

How tea may support cardiovascular health

Tea contains polyphenols, including flavonoids, which have antioxidant and anti-inflammatory properties. These compounds may help protect the cells lining blood vessels and support the ability of arteries to relax and expand. Such effects could help lower blood pressure and reduce strain on the heart.

Previous studies have also linked tea consumption to modest improvements in blood pressure, cholesterol and other indicators of cardiovascular health. These effects may partly explain why regular tea drinkers have been found to experience fewer strokes, heart attacks and other complications.

Choosing unsweetened tea instead of sugary drinks may offer additional benefits. Replacing soda or other sugar-sweetened beverages with unsweetened tea can reduce added sugar intake, supporting weight management and metabolic health.

Is black tea better than green tea?

Both black and green tea come from the same plant, Camellia sinensis. Their different processing methods result in differences in the types and amounts of polyphenols they contain.

In this study, black tea showed more consistent associations with lower cardiovascular risk, but green tea also appeared beneficial. Dr. Wen said there was no reason for people who enjoy one variety to switch to the other. Both can be part of a heart-healthy diet, particularly when consumed without added sugar.

How much tea is too much?

Among participants who drank tea at least weekly, the lowest estimated risk of vascular disease was observed among those consuming approximately six to eight cups a day. At higher levels of consumption, the estimated risk began to rise again.

The researchers cautioned against treating this finding as a recommendation to drink six to eight cups daily. The study did not use a standardized cup size, and tea consumption was self-reported. The results therefore do not establish an optimal daily intake.

Caffeine is another consideration. An eight-ounce (approximately 240-milliliter) cup of black tea typically contains about 30 to 50 milligrams of caffeine, while green tea generally contains less. Most varieties still contain caffeine unless specifically labeled caffeine-free.

The US Food and Drug Administration says that up to 400 milligrams of caffeine per day is not generally associated with dangerous effects in most adults. Pregnant people are advised to limit daily caffeine intake to 200 milligrams, while children should avoid caffeinated drinks.

Let tea cool before drinking

The practical advice is simple: avoid tea hot enough to burn the mouth or throat. Repeatedly consuming very hot beverages has also been associated with an increased risk of esophageal cancer. Allowing tea to cool until it can be sipped comfortably can help prevent burns.

People can choose black, green or other teas according to their preferences, while keeping an eye on their total caffeine intake, particularly if they experience sleep disturbances, anxiety or palpitations.

Those who do not drink tea do not need to start for the sake of their heart. Regular physical activity, avoiding smoking, maintaining healthy blood pressure and cholesterol levels, and following a nutritious diet remain important ways to reduce cardiovascular risk.

The study suggests that tea may be one part of a heart-healthy lifestyle, but both drinking temperature and overall consumption habits deserve attention. Its findings show associations rather than proving that tea itself prevents cardiovascular disease.