Hint: you can't, because it doesn't. More likely the contrary (as in: seeing a naked body every now & then lets kids grow up to be healthy adults). As has been shown at least a few times in serious studies
The best way for anyone to see how this is true is to see what goes on at a Nudist park, village, beach, etc. and my direct study (this summer) of the situation confirms your answer. Nudity != sex in spades. Also, people talk about body acceptance. If a nudist camp experience can't give you that with bodies all over the spectrum, then you really do need help.
I joined Cedar Waters Village http://nhnude.com/ this year, after a lifetime of avoiding places like that (except for that one visit to Moonstone Beach (PPTJLC)), and I can only say that I regret not doing something like this sooner in my life. The ability to just walk out of your cabin after waking up - bypassing your clothes hanging in the closet completely - and traipse off to the beach not giving a single flying fuck is refreshing.
BMO - Piping Plovers Taste Just Like Chicken