Tea, the most popular beverage on Earth after water, is also a wellness powerhouse. Studies suggest the drink has potential antioxidant, antibacterial, anti-inflammatory, anti-diabetic, and even anti-cancer effects.
Now, scientists say drinking tea more than three times a week is linked to living longer — and it could help stave off age-related diseases, like heart disease and stroke.
The new study, which examined 100,902 people in China, suggests that people who drink tea frequently have major health advantages over non-tea drinking counterparts. In this population, habitual tea drinkers were 20 percent less likely to develop incident heart disease and stroke, 22 percent less likely to die from a heart attack or stroke, and 15 percent less likely to die of any cause during the observation period, compared to non-habitual or non-tea drinkers.
These findings were published this week in the European Journal of Preventive Cardiology.
This study suggests habitual tea drinking can promote longevity and prevent disease. The researchers estimate that a 50-year-old tea drinker who sips habitually is more likely to develop heart disease, or experience a stroke, nearly 1.5 years later and live 1.26 years longer, compared to those who rarely drink tea.
However, one cup won’t do the trick. Harnessing tea’s health properties requires the frequent consumption of at least three times per week.
To reach these findings, the team analyzed the lifestyles and health metrics of a large, healthy study population without a history of heart attack, stroke, or cancer. The data was drawn from the China-PAR project.
The group was split by tea-drinking habits: Those who consumed tea more than three times a week were classified as “habitual” while those who drank the beverage less than three times were “non-habitual.” The researchers tracked the participants for an average of 7.3 years, gathering data through standardized questionnaires and medical tests.
In turn, they found that people who weren’t consistent with drinking tea, or jumped on and off the tea wagon, didn’t receive the same longevity-related benefits.
That’s likely because the tea’s body-boosting effect stems from certain compounds in tea leaves, namely polyphenols like flavonols, theaflavins, and catechins. These properties have been known to reduce inflammation and act as antioxidants in the body, which help prevent or control free radicals from damaging cells. Coffee also contains polyphenols, which may lead to similar health benefits.
“Mechanism studies have suggested that the main bioactive compounds in tea, namely polyphenols, are not stored in the body long-term,” Dongfeng Gu, senior author on the study and researcher at the Chinese Academy of Medical Sciences, explains.
Therefore, consistent intake over an extended period may be necessary for the cardio-protective effect, Gu says.
What type of tea is the healthiest?
Not all types of tea are created equal: When delineated by type, the research team found that only people who drank green tea had these positive health effects, not those who drank black tea. Black tea undergoes a fermenting process before it reaches the cup, which can diminish the number of healthy polyphenols.
However, the study population was dominated by green tea drinkers: 49 percent of the sample drank green tea, while 8 percent of the sample preferred black. So further study on all tea types is needed before scientists can definitively say which varieties have the strongest influence on disease and mortality.
Limits to the research
This isn’t the first study that has aimed to pin down the exact health effects of drinking tea — and previous research has been mixed. While some studies suggest similar disease-fighting benefits, others have failed to make the same positive connections.
Furthermore, other confounding factors may be at play. It’s entirely possible that tea drinkers maintain other habits that manifest a longer, healthier life, like exercise or consuming fewer foods high in sugar or saturated fat.
Before you start downing matcha lattes, experts caution green tea isn’t a “magic bullet”. The benefits may help boost health, but shouldn’t replace habits like maintaining a nutrient-rich diet and active approach to life.
Aims: The role of tea consumption in the primary prevention of atherosclerotic cardiovascular disease remains unclear in cohort studies. This prospective cohort study aimed to investigate the associations of tea consumption with the risk of atherosclerotic cardiovascular disease and all-cause mortality.
Methods: We included 100,902 general Chinese adults from the project of Prediction for ASCVD Risk in China (China- PAR) in 15 provinces across China since 1998. Information on tea consumption was collected through standardized questionnaires. Outcomes were identified by interviewing study participants or their proxies, and checking hospital records and/or death certificates. Cox proportional hazard regression models were used to calculate hazard ratios and their corresponding 95% confidence intervals related to tea consumption.
Results: During a median follow-up of 7.3 years, 3683 atherosclerotic cardiovascular disease events, 1477 atherosclerotic cardiovascular disease deaths, and 5479 all-cause deaths were recorded. Compared with never or non-habitual tea drinkers, the hazard ratio and 95% confidence interval among habitual tea drinkers was 0.80 (0.75–0.87), 0.78 (0.69– 0.88), and 0.85 (0.79–0.90) for atherosclerotic cardiovascular disease incidence, atherosclerotic cardiovascular disease mortality, and all-cause mortality, respectively. Habitual tea drinkers had 1.41 years longer of atherosclerotic cardiovascular disease-free years and 1.26 years longer of life expectancy at the index age of 50 years. The observed inverse associations were strengthened among participants who kept the habit during the follow-up period.
Conclusion: Tea consumption was associated with reduced risks of atherosclerotic cardiovascular disease and all-cause mortality, especially among those consistent habitual tea drinkers.