Dihydroxyacetone (DHA) is used in cosmetic products to darken the skin chemically, providing sunless tanning. It is considered nontoxic and noncarcinogenic.
Previously, studies have shown that DHA induces concentration-dependent photoprotection against UV-A and visible light.1 Commercialproducts containing DHA are often labeled as having no sun protection. However, our laboratory has shown that DHA absorbs UV-B and delays photocarcinogenesisin hairless mice.2 We therefore examined whether DHA offers any protection against erythema in humans.
Faurschou A, Janjua NR, Wulf HC. Sun Protection Effect of Dihydroxyacetone. Arch Dermatol. 2004;140(7):886-887. doi:10.1001/archderm.140.7.886