Which compound is the main active ingredient in many sunless tanning products?

Which compound is the main active ingredient in many sunless tanning products? The answer is dihydroxyacetone.

Dihydroxyacetone, commonly abbreviated DHA, is a simple three-carbon sugar and the main active ingredient in many sunless tanning products. It colors the outermost layer of skin without requiring ultraviolet exposure from sunlight or tanning beds.

DHA reacts with amino acids in keratin, the structural protein concentrated in the skin’s surface layer. This reaction, known as the Maillard reaction, creates brown compounds called melanoidins. The resulting color resembles a tan but is not the same as melanin produced by the skin in response to ultraviolet radiation.

The color develops gradually, usually over several hours, and fades as treated surface cells are naturally shed. DHA-based products come as lotions, sprays, gels, mousses, and wipes. A common misunderstanding is that a sunless tan provides meaningful sun protection: DHA does not replace sunscreen, and the artificial color does not prevent sunburn.