If chemicals harm ur hair, how re u supposed to take care of ur hair ?

if chemicls re harmful , then hw do u takecare of ur hair actulli ? u cannot go to the stone age nd wash ur hair wid oils ,egg yolk, flowers nd leav pastes ryt ! we re livin in a scientific world nd we re really busy wid work! we re forced to use shampoos ryt..WAT SHUD WE DO THEN ?