Tea can improve your health and longevity, but how you drink it matters

Tea is produced from the leaves of Camellia sinensis and has been consumed worldwide for centuries. It was first used mainly for medicinal purposes before becoming a widely enjoyed daily drink. Researchers have long been interested in tea because it contains high levels of polyphenols, especially catechins, which are believed to play a key role in its health effects. The review examines tea's influence on multiple health outcomes using evidence from laboratory research as well as human studies. While green tea has been studied extensively, much less is known about the health effects of other varieties, including black, oolong, and white tea, particularly when comparing their benefits. The review also considers potential risks tied to additives and contaminants found in some commercially produced tea beverages.

Study Highlights Gaps in Current Research

The findings were published in Beverage Plant Research by Mingchuan Yang & Li Zhou's team, Tea Research Institute, Chinese Academy of Agricultural Sciences. The authors emphasize that additional research is needed to more clearly define both the benefits and possible risks of tea consumption across different populations and tea types.

How Tea Affects the Heart, Metabolism, and Weight

According to the review, green tea stands out for its protective effects on the cardiovascular system. Studies show it can help lower blood pressure and improve cholesterol levels. Large cohort studies also suggest that people who regularly drink tea have a lower risk of death from all causes, reduced rates of CVDs, and a decreased likelihood of developing certain cancers. Tea may also play a role in weight management and diabetes control. Evidence indicates that green tea catechins can support weight loss and improve metabolic markers in individuals with obesity.

Brain Health and Muscle Preservation in Aging

Tea consumption is also associated with benefits beyond heart and metabolic health. Research suggests that regular tea drinkers, particularly older adults, show lower rates of cognitive decline and fewer biomarkers linked to Alzheimer's disease. In addition, tea catechins may help slow age-related muscle loss. This effect could support better muscle strength, physical function, and overall performance in seniors.

Potential Risks From Processed Tea Products

Despite tea's many advantages, the review cautions that not all tea products offer the same health value. Bottled teas and bubble teas often contain added sugar, artificial sweeteners, and preservatives that may weaken or offset tea's natural benefits. The authors also note concerns about pesticide residues, heavy metals, and microplastics found in tea. While these contaminants are not considered a significant risk for most people at typical intake levels, they may be more relevant for individuals who consume large amounts of tea over long periods. The review also discusses how tea can interfere with the absorption of certain nutrients, including non-heme iron and calcium, which may be important for people following vegetarian diets or those with specific nutritional requirements.

Freshly Brewed Tea Offers the Most Benefit

Overall, the review concludes that tea provides clear health benefits, especially when consumed in its traditional, freshly brewed form. Moderation is advised when it comes to processed options like bottled tea and bubble tea due to their added sugars and preservatives. The authors suggest that regular, moderate intake of brewed tea may help reduce the risk of cardiovascular diseases, diabetes, and cancer. They also note that future studies examining long-term consumption, differences among tea varieties, and the impact of contaminants will be essential for refining guidance on tea's health effects.