Drinking tea may help protect your heart, but there's a surprising catch - Science Daily

How a Massive Nine-Year Study Links Daily Tea Consumption to Vascular Health

Pouring a warm cup of tea might do more than offer a quiet morning ritual. A massive observational study tracking nearly 500,000 adults suggests that regular tea drinkers face a lower risk of developing several vascular diseases compared to those who skip the beverage entirely.

Science Daily reported on the findings from the research, which was published in the Journal of Internal Medicine. Following participants for a median of 9.05 years, researchers recorded 14,863 cases involving cardiovascular disease, cerebrovascular disease, pulmonary heart disease, and peripheral artery disease. The common thread among these conditions is that they interfere with blood circulation, restricting the flow of oxygen and vital nutrients to organs and tissues.

When the data was tallied, regular tea consumption was associated with an 11% lower risk of combined vascular outcomes. Among weekly tea drinkers, the lowest estimated risk showed up among those consuming approximately six to eight cups per day. Prevention noted that this figure does not mean everyone needs to drink that exact amount to see a benefit, nor does it guarantee that the beverage itself directly prevents disease, given the observational nature of the work.

Black Tea, Moderate Strength, and the Six-to-Eight Cup Sweet Spot

Not all brews performed the same in the data. Medical News Today highlighted that black tea showed more consistent associations with a reduced risk of vascular disease than green tea.

Strength mattered just as much as variety. Participants who favored moderate-strength tea showed the lowest associated vascular disease risk, meaning stronger brews did not automatically deliver greater protection. Still, experts urge caution against viewing these numbers as a strict prescription.

“Although the lowest estimated risk was seen at around six to eight cups a day, we shouldn’t treat that as a recommended amount,” said Dell Stanford, Senior Dietitian with the British Heart Foundation, speaking in a Science Media Centre debrief cited by Medical News Today.

The Burning Hot Exception to the Rule

While the overall trends favor pouring another cup, the study uncovered a striking caveat regarding temperature. Drinking tea described as “burning hot” was linked to an increased risk of vascular disease, pulling the data in the opposite direction.

Drinking tea may help protect your heart, but there's a surprising catch - Science Daily — Photo: Medical News Today

The Mirror noted that participants who preferred their tea burning hot actually faced a 16% higher risk compared to non-drinkers. Christopher Davis, M.D., chief cardiologist at Humann, pointed out this counterintuitive finding to Prevention, noting that very hot beverages expose tissues in the digestive tract and mouth to extreme temperatures. The study did not establish a specific biological mechanism behind this risk, nor did it define an exact temperature threshold where tea becomes harmful, relying instead on the subjective perceptions of the participants.

Why Lifestyle Habits Work Together for Cardiovascular Protection

Researchers also analyzed how tea drinking intersected with other daily behaviors, including smoking and physical activity. The lowest vascular risk appeared among individuals who maintained a combination of regular tea consumption, abstention from current smoking, and high levels of physical activity.

As Christopher Yi, MD, a board-certified vascular surgeon at MemorialCare Orange Coast Medical Center, explained to Medical News Today, antioxidants and polyphenols may help reduce inflammation and improve blood vessel function, but tea alone cannot manage cardiovascular health. The broader picture requires stacking healthy habits together rather than relying on a single dietary choice.