Originally Posted by kael03
lolwut? Nothing like this has ever been stated...anywhere. The only thing remotely mentioned about Susano'o's side effects is it plays hell on the cells. Considering it's a being manifested by the user's chakra, this makes more sense than it drawing on the life force of the user.
Itachi's sickness is likely based on the over use of sasanoo and where this comes from. itachi had a complete and full sasanoo plus added weapons which would have been hell on his body within the short time he had it. All the blood spitting said enough about the toll the jutsu took.
:Itachi spit blood from over using sasanoo and died at a young age mysteriously, tobi called a disease.
:nagato started spitting up blood when he over used devas power Shinrei Tensai, thus taking away some life. The jutsu shortens life span...http://www.mangakong.com/manga/Naruto/429/9
Clearly sasanoo like nagato's deva realm power when over used causes physical damage to the body taking years away. Life energy is the energy that governs the life of each person in the narutoverse and what hashiramas power of body was based on (extremely powerful life energy), which is likely used when causing the user to shorten ones life in these instances because merely overusing chakra doesn't shorten life span and cause blood spitting. Just hospitalization like with kakashi when he overused his chakra...