I think a better search would've helped. For example, doing a date limit to 2007 or so and searching tea human longevity OR lifespan OR mortality pulls up 2 correlational studies (what, you were expecting large RCTs? dream on). You could probably get even better results doing a human-limited search on Pubmed.
(what, you were expecting large RCTs? dream on)
Ahem.
You may say I'm a dreamer,
but I'm not the only one
I hope someday we'll randomize
and control, then we'll have fun
(Mediocre, but it took me two minutes. I'm satisfied.)
If it's worth saying, but not worth its own post, even in Discussion, it goes here.