Drinking tea at least three times a week is linked to a longer and healthier life, according to a Chinese study published on Thursday in the European Journal of Preventive Cardiology.
First author Dr. Xinyan Wang, researcher at the Chinese Academy of Medical Sciences, said in the report: "Habitual tea consumption is associated with lower risks of cardiovascular disease and all-cause death. The health effects are the most robust for green tea."
The analysis included 100,902 participants of the China-PAR project2, who were classified into two groups: habitual tea drinkers (three or more times a week) and never or non-habitual tea drinkers (less than three times a week) and followed-up for an average of three to seven years.
The study found that compared with never or non-habitual tea drinkers, habitual tea consumers had a 20% lower risk of incident heart disease and stroke, 22% lower risk of fatal heart disease and stroke, and 15% decreased risk of all-cause death.
The potential influence of changes in tea drinking behavior was analyzed in a subset of 14,081 participants. Habitual tea drinkers who maintained their habit in both surveys had a 39% lower risk of incident heart disease and stroke, 56% lower risk of fatal heart disease and stroke, and 29% decreased risk of all-cause death.
Senior author Dr. Dongfeng Gu from the Chinese Academy of Medical Sciences, said: "The protective effects of tea were most pronounced among the consistent habitual tea drinking group. Mechanism studies have suggested that the main bioactive compounds in tea, namely polyphenols, are not stored in the body for a long term. Thus, frequent tea intake over an extended period may be necessary for the cardioprotective effect."
The distinction of green tea comes from the fact that it is a rich source of polyphenols which protects against cardiovascular disease and its risk factors, including high blood pressure and dyslipidemia.
Black tea is fully fermented and during this process polyphenols are oxidized into pigments and may lose their antioxidant effects. Black tea is also often served with milk, which previous research has shown may counteract the favorable health effects of tea on vascular function.
