Habitual Tea Drinking Lowers Risk of Cardiovascular Disease, Death

January 9, 2020
Patrick Campbell

A new study has found habitual tea drinkers lowered their risk of atherosclerotic cardiovascular disease, coronary heart disease, and stroke compared to never or non-habitual tea drinkers.

While an unending amount of studies have examined potential cardiovascular effects of coffee consumption, new data from a team of Chinese investigators indicate tea drinkers have a reduced risk of atherosclerotic cardiovascular disease(ASCVD) and all-cause mortality.

The study, which examined more than 100,000 Chinese adults, found habitual tea drinkers had 1.41 more ASCVD-free years and a life expectancy 1.26 years longer than those who did not consume the beverage.

In an effort to assess the role of tea consumption in the prevention of atherosclerotic cardiovascular disease, investigators systematically examined associations between tea consumption and ASCVD morbidity and mortality in a cohort of 100,902 adults form the Prediction of ASCVD Risk in China (China-PAR) study. Initially, 105,263 patients with at least 1 year of follow-up were identified for inclusion but 1896 were excluded due to history of ASCVD or cancer at baseline and 2465 lacked data on tea consumption.

Tea consumption was assessed through face-to-face questionnaires at baseline and during follow-up visits. Tea consumption was classified as habitual if consumed 3 or more times per week or never or non-habitual tea drinkers, which was defined as less than 3 times per week. Investigators noted respondents were also asked to identify the most frequently consumed type, such as green tea and black tea.

Investigators obtained data related to demography characteristics, risk factors, and medical history via standardized questionnaires. Participants also underwent blood pressure measurements, as well as having blood drawn after fasting to test blood glucose and blood lipid levels.

The primary outcome of the study was ASCVD, which investigators defined as the first occurrence of nonfatal acute myocardial infarction, or coronary heart disease (CHD) death or a fatal or non-fatal stroke. Outcomes were verified through follow-up surveys and hospital or death records.

Within a median of 7.3 years of follow-up, a total of 3683 ASCVD events, 1477 ASCVD deaths, and 5748 all-cause deaths occurred among study participants. In total, 777,163 person-years were included in the analysis. Almost a third (31.6%) of participants were classified as habitual tea drinkers—48.2% of men and 20.4% of women. The most commonly consumed type of tea among habitual tea drinkers was green tea, which was preferred by 49% of drinkers, followed by black tea at 8% and the remaining 43% preferred scented tea or other types.

In comparison with never or non-habitual tea drinkers, investigators observed lower multivariate-adjusted hazard ratios (HR) in regard to ASCVD (HR:0.80; 95% CI, 0.75—0.87), CHD (HR: 0.82; 95% CI, 0.70–0.96), and stroke (HR: 0.80 95% CI, 0.73–0.87). Investigators also observed association with habitual tea drinking and ASCVD (HR: 0.78; 95% CI, 0.69–0.88), stroke (HR: 0.73 95% CI, 0.63–0.86), and all-cause mortality(HR: 0.85; 95% CI, 0.79–0.90).

Based on the results of the analyses, investigators calculated habitual tea drinkers could have 1.41, 0.32, and 1.23 years of delay in the development of ASCVD, CHD, and stroke, respectively, compared to never or non-habitual tea drinkers. Furthermore, the life expectancy for habitual tea drinkers was 1.26 years longer at the index age of 50 years.

In an editorial commentary published in the European Journal of Preventive Cardiology, a team of authors from the University of Perugia’s department of medicine hailed results of the study and the potential implications of the data.

“These results have important interpretative repercussions. The first and even more obvious interpretation is that tea consumption may provide overall health benefits and cardiovascular protection,” authors wrote. “The second interpretation is that an exposure-response relationship between tea consumption and health outcomes exists, in which both the amount of tea consumed, and the duration of tea drinking modulate this prospective association.”

This study, titled “Tea consumption and the risk of atherosclerotic cardiovascular disease and all-cause mortality: The China-PAR project,” was published in the European Journal of Preventive Cardiology.