Fake Tan: How safe are the products available?

I burn in the sun, so I never succeed in getting a tan. I'm thinking of using an artificial tanning lotion. How safe are the products available?

Dr Fred Kavalier answers your health question:

Most "sunless" tanning lotions contain dihydroxyacetone (DHA). This is a relatively simple, sugar-like chemical that only gets into the outermost layer of skin. The chemical is colourless when you apply it, but when it contacts the skin it reacts with amino acids on the skin and begins to darken. It is considered to be safe because it is not absorbed into the body. The colour disappears as the skin's surface cells naturally die. The colour can be maintained if you continue to apply the lotion at regular intervals. The best way to get an even colour is to prepare the skin beforehand. Use a loofah to exfoliate the skin and then wipe down the skin with an acidic toner to remove any soap. The best way to avoid streaking is to use a preparation that contains a low concentration of DHA (sometimes marketed as "light"). Make sure you wash the lotion off your hands, or you will end up with tan palms.

Please mail your questions for Dr Fred to health@independent.co.uk. He regrets that he is unable to respond personally to questions.