Self-tanners use chemicals instead of the sun to give you a suntanned look. Today’s self-tanners are colorless and induce your skin to change its color rather than simply applying a dye. This change, however, does not mean that you have the same protection from the sun that a real tan can give you.
The chemicals in self-tanners determine how quickly the “tan” will develop and the tone which you will achieve. Dihydroxyacetone (DHA) and erythrulose are combined in different proportions, creating different tones and different speeds of development. DHA creates color more quickly than erythrulose, and has more of a bronze color. Erythrulose develops more slowly, adds red to your tan to give it a more natural look, and helps the tan last longer.