What You'll Get
Sunless Tanning: Give Your Skin Some Sugar
A spray tan is obviously different from sunbathing, but it’s also more complex than simply painting over the skin. Check out our explanation to learn the science behind sunless tanning.
Besides covering your body in beige post-its, there are two primary ways to get a rich, deep tan without exposure to UV rays: bronzers and self-tanners. Based on a combination of moisturizers and tinted powders, bronzers stain the skin to darken it temporarily, resulting in a synthetic tan that can easily be scrubbed off with soap and water. Self-tanners, meanwhile, actually affect the skin on a cellular level, emulating the natural effects of sunlight to create a lasting color. Available in forms ranging from lotions to airbrush sprays, self-tanners make use of a colorless sugar compound called dihydroxyacetone, more commonly known as DHA.
When applied to the skin, DHA triggers a safe chemical reaction—similar to the browning effect on bread’s outer crust—in amino acids on the skin’s surface, producing complex polymers called melanoidins. These polymers exhibit a darkened appearance virtually identical to the natural pigmentation caused by melanin during UV exposure. Unlike sun tanning, however, this process only affects the cells in the outermost layer of the epidermis, and since the body sloughs off millions of surface-level skin cells everyday—billions when we wear our trendiest sandpaper suits—sunless tans tend to fade in 7 to 10 .