Male Health and Dress

The pictures shows members of the Druze community in Syria. Note their trousers with the wide skirt allowance attached to the trousers from the waist down. This may be the best solution for the male condition in existence from the health point of view.

Underwear in winter provides additional warmth and protection. Pure un-polished cotton is recommended. Synthetics do not absorb sweat so well, cause irritations, and the static electricity may be an unrealized cause of discomfort.
In summer underwear also provides additional protection, hides stains from urinal remnants, and also helps conceal private parts otherwise perceivable under strong light or after excessive sweating.
 On the other hand, in TROPICAL areas with high humidity when engaged in physical exertion going without underpants is preferable especially when wearing cotton trousers. Based on my own experience and the anecdotal remarks of others this greatly reduces the incidence of skin rashes and the like.

Incidentally, underpants when worn should be large and comfortable. If they are too tight it could cause mental tension and, in the long run, adversely affect fertility. The gonads should be distanced from heat and radiation. They say that kilts without underpants are the best option for health reasons but this is socially unacceptable and impracticable for other reasons.