if yes .... why ??
My coach had all of us drinking one cup warm tea and eating 2 pieces of dry toast before all our cc races in college and it never seemed to bother any of us. He said the combination of the two helped put something on the stomach without unsettling it. I never experienced problems with any need for more frequent urination or anything so in my case and my teammates so far as I know it worked out okay. It could be an old wives tale or superstition he passed on to us but I still stick to that whenever I race and have for almost 20 years. The guy was an all american at FSU so I give him the benefit of the doubt that there is something to what he said.
If you mean before you run then no, it's not a good idea. I drank tea before my 1/2 marathon and around mile 5 had to get in line at the port-o-potty (which added 5 minutes to my time).
But if you mean drinking tea in general then yes, it's good for you.