Board Thread:Theories and Speculation/@comment-3568954-20141031085827/@comment-1210805-20141031094608

Actionmanrandell wrote: TheUltimate3 wrote: Kishimoto decided that Creation Rebirth shortening her life is what is making her look old, to show that her lifespan is short. And we have no idea how much she used it during her time outside of Konoha? Or hell during the war.

never once have they said in the manga or in any interviews that creation rebirth makes her look older than she does

No, but it has blatantly said that it accelerates the duplication of her cells and in turn, shortens her lifespan. It's pretty clear that Kishi's intent is to say that that increased cell division speeds up her aging.