Tea drinkers had an 11% lower heart risk, but burning-hot tea undercut the benefit

A team led by Zichen Ye of Peking Union Medical College followed 485,934 adults in China for a median of 9.05 years and found that regular tea drinkers had about an 11% lower risk of vascular disease than people who did not drink tea. The same study found a catch: tea described as burning hot was linked to higher risk. The work appeared in the Journal of Internal Medicine, and Wiley issued the press release that reached the public on Nov. 1.

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Observational findings of this kind show a pattern across a population. They leave open why the pattern exists.

485,934 adults and 14,863 vascular cases

The paper, titled Habitual tea consumption is associated with lower cardiovascular disease risk, tracked participants until 14,863 of them developed a vascular disease. The outcomes were pooled: cardiovascular disease, cerebrovascular disease, pulmonary heart disease and peripheral artery disease. The 11% figure applies to that combined group compared with non-drinkers, so it covers more than heart attacks alone.

The ScienceDaily write-up of the release adds that the lowest estimated risk among people who drank tea at least weekly came at about six to eight cups a day. Intake was recorded once, as reported by participants, and cup size was not standardized, according to a Sci.News report on the study.

The raw count puts the finding in proportion. Out of 485,934 participants, 14,863 developed a vascular disease over the follow-up, or roughly 3 in every 100. As an illustration only, an 11% lower relative risk applied to a baseline near 3 in 100 would mean about a third of a case fewer per 100 people over nine years. The study reports the relative figure, and the absolute gap for any one drinker could be smaller or larger than that sketch.

The four outcomes bundled into those cases are different diseases. Cerebrovascular disease covers strokes and related disease of the brain’s blood vessels, pulmonary heart disease is strain on the right side of the heart that originates in the lungs, and peripheral artery disease is narrowing of arteries outside the heart and brain. The coverage does not break out how many cases fell into each category or give separate estimates for each, so the 11% figure cannot be assigned to any single condition.

Black tea, moderate strength and the best lifestyle pairing

Black tea showed more consistent links to lower risk than green tea, and moderate-strength brews tracked with the lowest risk while stronger tea showed no extra benefit. The authors could not say whether polyphenols explain the black-versus-green difference. Their summary of the best-off group was that habitual tea drinking, not currently smoking and high physical activity were associated with the lowest risk of all, which places tea inside a set of habits and not on its own.

Burning-hot tea and what the data cannot say

The authors called the burning-hot result the study’s most surprising finding. Drinking tea that participants described as burning hot was associated with higher risk, which cancels some of the advantage regular drinkers otherwise had. The study identified no temperature threshold and no biological mechanism, and the hot-tea association does not prove that very hot tea causes vascular disease. The wording came from the participants, so one person’s burning hot may be another’s lukewarm.

Very hot drinks already have a separate research history. The International Agency for Research on Cancer devoted a monograph volume to coffee, mate and very hot beverages, which shows that scientists have scrutinized beverage temperature for years in contexts outside heart health. The Chinese cohort did not test whether the cardiovascular signal and that earlier line of work share a cause. Self-description is the weak joint in the hot-tea result. Temperature was not measured at the cup, and participants chose their own category and the burning-hot group reflects a perception of heat. Because tea intake was recorded at a single point, a person who changed habits after enrolling would still sit in the original group.

The authors themselves decline to turn the result into advice. They write that drinking more tea does not necessarily prevent disease, and the study sets no recommended intake. The six-to-eight-cup low point describes where the estimated risk sat among weekly drinkers in this cohort, which is a description of the data and not a target.

Outside experts on diet, income and exploratory findings

Two researchers not involved in the study urged caution. Dr. Charalampos Rallis of Queen Mary University of London said the model was not fully adjusted for diet and income, and that some results, including those on black tea and very hot tea, should be treated as exploratory. Dr. Dell Stanford of the British Heart Foundation said the findings do not prove that a daily cup protects the heart and stressed overall diet and lifestyle.

The stakes of any real effect are large. The Centers for Disease Control and Prevention says heart disease is the leading cause of death in the United States, accounting for 1 in 5 deaths, or 22%. Even so, the study team itself said the work could not establish that tea was responsible for the differences, and it set no recommended intake. The question the paper leaves for later work is causal: whether tea changes vascular risk, or whether tea drinkers differ from non-drinkers in ways the adjustments missed. The authors say more research is needed to settle it.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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