Tea's health benefits get a high profile article in NBCNews.com. The author shares her interest in the health benefits of tea before sharing the research:
"For most of my life, I’ve considered tea a bland beverage that leaves something to be desired. All of that changed when I moved to Germany, the underrated mecca for tea aficionados. Here, tea shops abound, you can find every herb out there in tea form, and tea is even prescribed by medical doctors and found in pharmacies."
They do a great job of summarizing and linking the relevant research:
Beyond L-theanine, tea continues to be researched as a rich source of antioxidants called flavonoids, mostly found in green and black tea. Research has found that these flavonoids might reduce the risk of cardiovascular disease and stroke and could be related to cardiovascular mortality risk. In one meta-analysis published in “Advances in Nutrition,” just a 1-cup increase in daily tea consumption was associated with a 2 percent decrease in any cardiovascular event. However, more research needs to be done to demonstrate any proven benefits.
For caffeinated tea drinkers, there are even more benefits to be found in tea. Caffeine has often been cited as a driver of physical health benefits, including a lowered risk for type 2 diabetes, cardiovascular disease and colon cancer, though more research needs to be done to prove any definitive links. There are also some potential mental health benefits: In a study of more than 50,000 women, those who drank at least four cups of caffeinated coffee a day saw a 20 percent reduced risk of depression compared to those who drank almost no coffee.