In spite of its markedly decreased importance on the cosmetic scene, dihydroxyacetone (DHA) continues to be of interest to dermatologists.1-6 Studies are still needed to attempt to develop a better color, to understand its absorption and its effect on local and systemic carbohydrate metabolism and its effect on various enzyme systems.4 Flesch and Esoda state that "in spite of its unknown chemical effect and doubtful clinical status, DHA may become an interesting experimental tool."
Through cooperative studies with Guest and Wittgenstein and Berry,8,9 we have reported investigations of the mechanism of the reaction,1 some physical characteristics of the color complex,5 some toxicologic studies,4 and our experiences with the topical use of DHA in clinical dermatology.6 Obviously, we need more information on the first phase of the reaction, as Flesch and Esoda indicate; more knowledge of the pigment formed, more studies to improve