Why Do Self-Tanners Smell So Bad?

Question: Why Do Self-Tanners Smell So Bad?

Answer: Self-tanners contain a chemical called dihydroxyacetone (or DHA) which has an unpleasant odor. These days companies try to mask the DHA smell with essential oils, but every self-tanner I've tried has some sort of DHA odor, some stronger than others. Self-tanners tend to start smelling a couple hours after application. I think the combination of product with natural body heat makes the smell more obvious.