It all depends on how you have it. If you are one of those who has tea with milk, you could be destroying the health benefits, which otherwise come with it. Based on research done by some German researchers and the European heart journal and published in the Daily Mail, tea with milk has little or no impact on the prevalence of heart disease because you add milk. Similarly black tea significantly improves the ability of the artery to relax and expand (the nitric acid in tea promotes dialation of blood vessels), but milk blocks this effect.
I have conciously moved away from Coffee to tea a year back, purely for its health benefits (similarly from white wine to red), even though I enjoy coffee more. And luckily it was black tea. Not sure if its helped me, but it should come to my rescue in the long run.
Another benefit of my Delhi trip is that now I am very comfortable runing in cold climate and this should come in handy for my Great Tibetan marathon in July. So the only thing I need to figure out is my ability to manage high altitude.