There is none.

I've been doing this NoFap for a year, I won't share any details regarding the rules that I follow. Opinions may vary, but the result of this personal experiment tells me that there seems to be no bad health side-effects that one may concern themselves with, and at times, it wasn't easy to keep myself from climaxing because of this heightened mood state that I often get. NoFap's rule is simple, no PMO, no porn, masturbation and orgasm are allowed. Anything out side of that is the rule that people can set for themselves, for me the primary reason for doing this is an ethical one, or I could say it's a simple life style choice that I made. I'm proud to be a fapstronaut today heading for another year of life explorations.