Look at it this way. Not knowing and not having the need to know, we can't even assume that, given the wisdom and ways of the professionals in the military there is any truth to this whole thing. What can be proved? The factors which create conditions which necessitate treatment, medically, are borne of the atmosphere. Some people react differently from others. Some smokers smoke all their lives and never get cancer. Others can not. Mortifying the flesh is a matter of personal choice and there is no standardized way to do it. "Work out your own salvation with fear and trembling."