Sunless tanning, or self-tanning, refers to the application of a lotion, gel or cream that most typically contains the ingredient dihydroxyacetone (DHA). DHA interacts with skin to impart a "tan" color--without having to risk exposure to the sun's harmful rays and sun damage.
Sunless tanners are considered safe to use. Multiple applications will deepen the shade of tan that skin appears. Once the desired color is achieved, it is necessary to reapply the sunless tanner every few days as the skin's natural exfoliation process will cause the sunless tan to fade.
In addition to lotions, gels and creams, there are spray-on tanning formulas for home use, and also professional spray systems that are applied in a specially designed booth at a salon or spa. Even though indoors, tanning beds are not considered "sunless" as they expose skin to damaging UV rays.
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