DHA is derived from glycerin (vegetable origin), which is a commonly used cosmetic and food ingredient. DHA has been used in cosmetic preparations for almost 30 years and was listed with the FDA in 1973. In addition to its skin darkening abilities, DHA is also used as an emulsifier, humectant and fungicide. It is declared safe and suitable for use in cosmetics and drugs used to color the skin. DHA is not absorbed into the body and poses no possibility of toxicity.
When DHA is applied to the skin; DHA reacts with proteins in your skin resulting in a brown “tan” which forms in about 2 to 3 hours. The tan continues to darken for approximately 6 hours. The result can be a quite pleasing dark tan. The tan is absolutely water-resistant and diminishes only as the dead cells of the stratum corneum flake off (exfoliation) – usually in 4-5 days. DHA is the closest you can get to a tan from the sun – without the associated risks.