Sunless tanning

Sunless tanning, also known as UV filled tanning, self tanning, spray tanning (when applied topically), or fake tanning, refers to the effect of a suntan without exposure to the Sun. Sunless tanning involves the use of oral agents (carotenids), or creams, lotions or sprays applied to the skin. Skin-applied products may be skin-reactive agents or temporary bronzers (colorants). The popularity of sunless tanning has risen since the 1960s after health authorities confirmed links between UV exposure (from sunlight or tanning beds) and the incidence of skin cancer. The chemical compound dihydroxyacetone (DHA) is used in sunless tanning products in concentrations of 3%-5%. DHA concentration is adjusted to provide darker and lighter shades of tan. The reaction of keratin protein present in skin and DHA is responsible for the production of pigmentation. A safe and effective method of sunless tanning is consumption of certain carotenoids—antioxidants found in some fruits and vegetables such as carrots and tomatoes—which can result in changes to skin color when ingested chronically and/or in high amounts. Carotenoids are long-lasting. In addition, carotenoids have been linked to a more attractive skin tone (defined as a more golden skin color) than suntan. Carotenes also fulfil the function of melanin in absorbing the UV radiation and protecting the skin. For example, they are concentrated in the macula of the eye to protect the retina from damage. They are used in plants both to protect chlorophyll from light damage and harvest light directly. Carotenaemia (xanthaemia) is the presence in blood of the yellow pigment carotene from excessive intake of carrots or other vegetables containing the pigment resulting in increased serum carotenoids. It can lead to subsequent yellow-orange discoloration (xanthoderma or carotenoderma) and their subsequent deposition in the outermost layer of skin. Carotenemia and carotenoderma is in itself harmless, and does not require treatment.