content: Ignore appeals of "but it's not ionizing radiation". Biological processes are extremely sensitive - with protein folding, there is only one correct way for the protein to fold, and as it folds, it's essentially following a path of least resistance.  If you have even moderate EM radiation, it can interfere with that path. So, with ionizing radiation, you have extra or missing electrons and this is obviously a problem.  But with non-ionizing radation, it can alter the forces at work in such a way that the process does not complete properly. Think of someone juggling balls.  You throw your own ball (ionizing radiation) and hit one being juggled, totally knocking it out of the loop.  But with non-ionizing, you still throw a ball at the ones being juggle and you graze it.  It doesn't get knocked out, but now the juggler could miss the catch / throw because the juggle loop has been disturbed.