People are becoming more aware of the danger that long sun exposure represents to human health. The awareness of risk of sunburns, premature skin aging and skin cancer determines an increasing popularity of sunless tanning. Sunless tanning, also called self-tanning, means obtaining a tan without exposing to the sun. There is a great diversity of sunless tanning products, but the most efficient and safe are considered to be dihydroxyacetone (DHA) products. What should we know about DHA?
Dihydroxyacetone is a carbohydrate that interacts with proteins from the outermost layer of epidermis - stratum corneum. DHA reacts differently to various amino acids form the external surface of the skin, producing different coloration, from yellow to dark brown. As a result a pigmentation effect close to sun tanning is obtained. Dihydroxyacetone products are rather safe as long as the chemical does not penetrate deeper than stratum corneum. That is why side effects are minimal. Although there are registered several cases of allergy to dihydroxyacetone products, most of them are caused by other product compounds, such as perfumes and preservatives, and only a few cases are caused by DHA allergy, manifested as contact dermatitis.
Tanning effect of dihydroxyacetone products begins after 1-2 hours after application and continues darkening the following 24-72 hours, depending on formulation. In order to keep the optimal tan, the product must be reapplied after 5-7 days. The fade away of the tan is happening because the dead skin cells are rubbed off, and new ones are taking their place. Sunless tanning products may be used by anyone who wants to have a healthy tan. As a medical indication it is used by patients with viteligo and certain photosensitivity disorders.
Sunless tanning products may contain different concentrations of DHA, from 1% to 15%. The concentration of DHA determines the intensity of the color. For new users it is recommended to start with lower concentrations. It is important to understand that sunless tanning does not offer protection from ultraviolet rays and artificially tanned skin must be protected when exposed to sun. Some sunless tanning products may have a certain SPF, but it is efficient for only a few hours (as any other sunscreen), but not until tan is maintained. So, even if you are using sunless tanning, don't forget about sunscreens, with a SPF 15 or higher.
Beside dihydroxyacetone products there are some other more or less reasonable alternatives for sunless tanning. Bronzers are available in powders, sprays and creams, and are basically a kind of make-up, because they can be easily washed away with water and soap. Tan accelerators actually are not really ?sunless? tanning products, as they still need solar rays to be efficient. They are based on a substance called tyrosine, which participate in melanin (natural skin pigment) production. However, scientists are still researching this type of products, as they may be dangerous for health.
Also there are tanning pills, based on canthaxanthin (color additive used in food), which have been banned in the United States because of their multiple side effects, such as liver damage (hepatitis) and canthaxanthin retinopathy. So, the most popular and safe sunless tanning products for the moment are dihydroxyacetone products.