The Self-Tanner Ingredients That Get You Glowing

In order for self-tanners to transform your skin from pale and pasty to golden and glowing, most contain dihydroxyacetone (DHA), a colorless chemical that darkens just the outer layer of skin and has no effect on your melanin.

DHA works with the protein in the uppermost layers of skin, essentially staining it to create a browner color. It's the same principle that causes sugar-containing foods to turn brown when they're kept in storage, since DHA is sugar-derived. The more DHA your self-tanner contains, the darker your skin will turn.

Sometimes DHA is supplemented by erythrulose, a naturally based sugar that reacts with the amino acids in the skin. Slower to develop and quicker to fade, erythrulose is believed to be less drying that DHA. However, it's usually used in addition to DHA because it can leave the skin with an orange cast if used alone.