Originally Posted by TheJkid
Just wondering.. where did the 10 years come from? I don't remember that at all. I know she ages from using the chakra from the seal to do a medical regeneration technique on herself, but never have I seen a number added on it.
Tsunade is always under a transformation jutsu, making her appear younger than she really is. When the seal wears off, she is usually exhausted to the point where she can't maintain that illusion any longer. In contrast to the last time she released the seal, during the Pain Arc she didn't use it to heal herself (Well, I would presume), but rather she channeled all the Chakra into everyone else. If thats the case, then she really wouldn't have aged from using it at all, since shortened-lifespan comes from the regeneration (as Kishi says) speeding up the rate at which cells divide.
So... either way, during the Pain arc, she is exhausted after giving out a huge amount of Chakra to protect everyone, that she can't maintain the Transformation anymore. Which doesn't mean she has aged any as a result.