Originally Posted by MrBIG
Tsunade and Hashimara's healing ability would probably prolong their life spans...
Actually the opposite is true. Cells can only divide a certain amount of times, therefore if you are constantly being wounded, and forcing your body (via medical jutsu) to replace lost cells then your overall life expectancy will begin to dwindle. Tsunade explained this a long time ago when she used her jutsu during the Sannin battle.