Nutrition

Nutritional Pearls: 3 Reasons To Drink More Tea

  • Over 15 years ago, a study out of China that showed an association between higher intake of green tea and lower risk of death from all causes as well as a 31% reduction in risk of death from heart disease for those women drinking 5 or more cups of green tea per day. In another study, drinking green tea regularly for 20 years or more was associated with lower risk of digestive system cancers, while black tea has been linked with a lower risk of ovarian cancer.

    Tea's positive effects on our health has been attributed to its high levels of antioxidants—polyphenols and a subtype, flavonoids, specifically—a feature shared to some degree by coffee, cocoa, and wine.

    The Research

    In today's article, an international team of researchers investigated tea consumption and cardiovascular disease, performing a meta-analysis of multiple prospective studies in the hopes of identifying results that might not be evident in a single, smaller study alone.

    The 39 studies included in their analysis ranged in length from 5 years to 24 years, with as few as 550 and as many as 487,000 participants. Each included study had to specifically report on tea consumption and be conducted in persons of at least 18 years of age who were generally healthy: no more than 20% of the participants in an included study could have diagnosed cardiovascular disease other than high blood pressure.

    For each type of outcome, ranging from all-cause mortality to cardiovascular mortality to stroke, the authors synthesized the results from those studies that reported on those outcomes.

    All-Cause Mortality

    After analyzing the 15 different studies that included all-cause mortality as an outcome, the authors found that each additional cup (8 ounces) of green or black tea was associated with a 2% lower risk of all-cause mortality, with stronger associations in those over the age of 65 years. The authors caution that these results were of comparatively low quality.

    Cardiovascular Disease Mortality (CVD)

    The 17 studies that were included in this analysis also showed a 4% lower risk of CVD mortality for each additional cup of tea—but again, the effects were stronger in those over 65 years of age at 11%.

    Risk Of Non-Fatal Cardiovascular Events Such As Heart Attack Or Stroke

    As with the results for causes of death, the 7 studies included in this analysis also showed a small—just 2%—reduction in risk of heart attack or stroke for every additional cup of tea.

    What’s the Take Home?

    There are no superfoods, and there is no magic bullet or supplement that will make you healthy—or even help you to lose weight. For long-term health, what's important is many smaller behaviors, like cutting back on red meat, avoiding highly processed foods as much as possible, ditching soda, and drinking another cup of tea (if you like tea), that will help you be healthier while also enjoying your life.

    Reference:

    Chung M, hao N, Wang D, et al. Dose–response relation between tea consumption and risk of cardiovascular disease and all-cause mortality: a systematic review and meta-analysis of population-based studies. Adv Nutr. 2020;11(4):790-814. https://doi.org/10.1093/advances/nmaa010