Self-tanning products provide a temporary colouration of the skin, which mimics the naturally sun-tanned skin. They are popular and widely used due to highly desired tanned skin and greater awareness of the harmful effects of the UV light.
The common ingredient used in these kinds of products is dihydroxyacetone (DHA). DHA is a self-tanning agent, which is responsible for the darkening of the skin by staining. The site of action is stratum corneum, where DHA as a sugar reacts with amino groups of the proteins in the top layer of the skin. This reaction is known as the Maillard reaction.
The result of self-tanning depends on the product formulation, application technique and user’s complexion type.
Measurement Principles and Instruments
Efficacy of self-tanning products is evaluated through comparison of the photos of before and after the application of the product.
Efficacy testing protocol is prepared for each product individually with close cooperation with the sponsor. Based on the claims, usage regime and efficacy expectations, we prepare a protocol that is suitable for the type of product and can confirm product efficacy. The studies can be performed over a different time period (from a few days to several weeks or months) depending on the claim and type of measurement.