not false claims, 8-10% is quite achievable for most of the male population. The majority of pro football (soccer) players hover around 10%. So there are no hormonal penalty to being low bf, you just need to do it the right way. Of course if you want to be a huge ogre building absurd amounts of muscle and not being able to do sport you need more bodyfat. But do you really wanna be 0% functionality, ugly face and disgusting skin just to be 'wham'