Sunless tanning has many advantages over the traditional sun tanning. Some people are unable to tan due to their melanocytes not being in working order. Sunless tanning avoids this problem as it does not require melanocytes. The active ingredient in many sunless tanning supplies is Dihydroxyacetone[DHA]. DHA saturates the dead skin cells at the surface of the outside layer of the skin, turning the dead cells brown (or tan color).Sunless tanning is completely safe. There is a common myth that.