The most important reason for most wetsuits being black is that this color is the most efficient at protecting wearers from the harmful effects of Ultra-Violet rays (UV rays). Black is the most effective photon absorber, which makes it an excellent shield against these rays. Black will also absorb and retain heat from the sun, which will go a long way in boosting the wetsuit’s heat-retaining qualities. It is, finally, a neutral color that very few people would mind wearing for whatever reasons.