A researcher at the Chinese Academy of Medical Sciences published a study that associates regular tea drinking with lower risks of cardiovascular disease. For the study, they tracked over 100,000 adults across 15 provinces in China for more than seven years. The drinkers who had at least three servings of tea a week lived 1.41 years longer than those who didn’t.
Tea drinkers are at about 22% lower risk of dying of heart disease or stroke and 15% less likely to die from other diseases. They also found through a smaller study that those who drank tea over longer periods reduced risk even more. This smaller group was followed for over eight years and those that drank tea more often had a 56% decrease of a chance of stroke or heart disease, and 29% less risk of dying of other illnesses.
Because the polyphenols are not stored long-term in your body, tea should be consumed frequently. The most health benefits are from green tea. Green tea is higher in polyphenols. Black tea loses some polyphenols during the process used to ferment it during production.
This study did not take into account diet or exercise so there may be other factors that could effect this outcome.