Well your body is affect by leukemia because once it starts taking out the white blood cells your body becomes weaker because there is nothing to fight off sickness so there really is no part of your body that leukemia does not effect.
If you want to serve but don't want to be in combat, sadly your gonna have find another job unless you want to do infantry.
Well it may help reduce energy but energy drinks are really bad since it has so much caffeine and sugar. Drinking too much can cause heart attacks, diabetes, and addiction.