A daily cup of tea is often associated with relaxation, but its potential value may extend beyond comfort and enjoyment. Research published in October 2026 suggests that habitual tea consumption may be linked to a lower risk of cardiovascular disease. The findings also indicate that tea variety, brewing strength and serving temperature could influence this relationship.
The study, published in the Journal of Internal Medicine, examined nearly half a million adults in China over approximately nine years. Although the results add to growing interest in tea and cardiovascular health, they do not establish that drinking tea directly prevents disease.
<h3>What the Researchers Found</h3>
The research team analyzed health and lifestyle information from 485,934 participants aged between 30 and 79. Participants reported how frequently they consumed tea, the varieties they preferred, how strongly they brewed it and the temperature at which they usually drank it.
During an average follow-up period of just over nine years, researchers recorded 14,863 new cases of vascular disease. People who regularly drank tea had an estimated 11% lower relative risk compared with those who did not consume it regularly.
The analysis also identified differences across tea-drinking habits. Among regular consumers, the lowest estimated risk appeared in people drinking approximately six to eight cups per day. Moderate-strength tea was also associated with more favorable results than very weak or particularly strong preparations.
<h3>How Tea Compounds May Influence Blood Vessels</h3>
Tea contains plant compounds called polyphenols, including flavonoids and catechins. Such compounds have attracted scientific interest because of their potential antioxidant and anti-inflammatory activity. Oxidative stress occurs when the production of reactive molecules exceeds the body's ability to control them. Over time, this imbalance can contribute to cellular damage and changes in blood vessel function. Polyphenols may help influence some of the processes involved.
Another area of interest is the endothelium, a thin layer of cells lining blood vessels. It helps regulate vessel flexibility and blood flow. Some studies suggest that tea compounds may support endothelial function, although results from laboratory experiments and clinical trials do not always translate into measurable long-term benefits.
<h3>Black Tea and Green Tea: What Sets Them Apart?</h3>
Black tea and green tea come from the same plant, Camellia sinensis, but their processing methods produce different chemical profiles. Green tea is minimally oxidized and retains substantial amounts of catechins. Black tea undergoes greater oxidation, creating compounds such as theaflavins and thearubigins.
In the 2026 study, black tea showed more consistent associations with lower vascular risk than green tea. However, this does not prove that black tea is more protective. Differences in preparation, dietary patterns and other lifestyle characteristics may have influenced the results.
<h3>Why Brewing Strength and Temperature Matter</h3>
The researchers observed that moderate-strength tea was associated with more favorable outcomes than very weak or strong tea. However, the study does not establish an ideal brewing time or a precise concentration that guarantees better health. Serving temperature produced another notable finding. Participants who preferred tea described as “burning hot” had an estimated 16% higher relative risk of vascular disease than people who did not regularly drink tea.
The researchers did not measure each participant's beverage temperature with a thermometer. Instead, they relied on personal descriptions, which can vary considerably. Even with this limitation, allowing tea to cool to a comfortable sipping temperature is a sensible habit. Repeated exposure to extremely hot beverages can damage tissues in the esophagus.
<h3>Expert Insight</h3>
Michelle Routhenstein, a preventive cardiology dietitian at Entirely Nourished, explained why tea should be considered part of a broader approach to cardiovascular health. Speaking to Healthline, she stated: “Tea can be a helpful addition to a heart-healthy lifestyle, but it is not a substitute for addressing individual cardiovascular risk factors.”
<h3>How Much Tea Is Appropriate?</h3>
Although the lowest estimated risk in the study appeared among people drinking around six to eight cups daily, this amount should not be treated as a universal recommendation. Cup sizes were not standardized, and participants reported their habits themselves.
Caffeine content also varies according to tea variety, serving size and brewing duration. High intake may cause restlessness, sleep disruption or palpitations in people who are sensitive to caffeine. Those effects are worth considering when deciding how much tea fits comfortably into a daily routine.
The findings support further investigation rather than a strict daily drinking target. Tea can be an enjoyable part of a balanced routine, while long-term cardiovascular health still depends on several connected lifestyle habits.
