A cup of tea may still be doing some heavy lifting. A major review says tea, especially green tea, may help protect against heart disease, obesity, diabetes, some cancers, cognitive decline and age related muscle loss, but bottled and bubble teas can come with extras that cut into those benefits.
The review was published in Beverage Plant Research by Mingchuan Yang and Li Zhou’s team at the Tea Research Institute, Chinese Academy of Agricultural Sciences.
According to the summary provided by Maximum Academic Press, the review found that tea plays a key role in preventing cardiovascular diseases, obesity, diabetes and certain types of cancer. It also pointed to tea’s neuroprotective effects, its ability to reduce muscle loss in older people, and its anti-inflammatory and antimicrobial activity.
Tea is made from the leaves of Camellia sinensis and contains polyphenols, particularly catechins, which are linked to its health effects.
The review said green tea was highlighted for cardiovascular protection, including reducing blood pressure and improving cholesterol levels. It also said multiple cohort studies showed regular tea consumption could lower the risk of all-cause mortality, cardiovascular disease and certain cancers.
On weight and diabetes, the review said evidence suggests green tea catechins can help with weight reduction and improve metabolic measures in people with obesity.
It also found tea showed promise for brain health and muscle preservation. Studies cited in the review indicated regular tea drinkers had a lower prevalence of cognitive decline and Alzheimer’s disease biomarkers, particularly in older adults. Tea catechins may also help prevent muscle loss in seniors, contributing to better physical performance and muscle strength.
But the review also flagged concerns about commercial tea drinks. Bottled tea and bubble tea often contain sugar, artificial sweeteners and preservatives, which the review said may reduce or negate tea’s health benefits.
It also raised concerns about pesticide residues, heavy metals and microplastics in tea. The summary said those contaminants do not appear to pose significant health risks in typical consumption, but remain a concern for long-term heavy tea drinkers.
The review also addressed nutrient absorption, saying tea can interfere with non-heme iron and calcium absorption. It said that could affect vegetarians and people with specific nutritional needs.
According to Maximum Academic Press, the researchers said the findings support moderate consumption of traditional, freshly brewed tea, while calling for further research on the long-term health effects of different tea types and the impact of contaminants.
The paper is titled “Beneficial health effects and possible health concerns of tea consumption: a review.”
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