Intro: Sun tanning describes a darkening of the skin color (especially of fair-skinned animals) in a natural physiological response stimulated by exposure to ultraviolet (UV) radiation from sunshine or from artificial sources such as a tanning bed. Only a handful of animal species including pigs, humans and certain sharks have skin that darkens in response to sunlight. With excessive exposure to ultraviolet, a sunburn can develop.Health Benefits: The skin produces vitamin D in response to sun exposure (in particular, UBV in the 295-297 nm range), which can be a health benefit for those with vitamin D deficiency. In 2002, Dr. William B. Grant published an article claiming that 23,800 premature deaths occur in the US annually from cancer due to insufficient UVB exposures (apparently via vitamin D deficiency). This is higher than 8,800 deaths that occurred from melanoma or squamous cell carcinoma. This does not mean that sun tanning is categorically safe or beneficial. Spending several minutes in the sun is long enough to obtain your daily dose of vitamin D. Other research estimates that 50,000–63,000 individuals in the United States and 19,000 - 25,000 in the UK die prematurely from cancer annually due to insufficient vitamin D.
Reducing Skin Cancer Risks: If long sun exposure cannot be avoided or is desired one may use sunscreen or various over-the-counter creams to reduce sun exposure. The SPF (Sun Protection Factor) number on a sunscreen product shows its rated effectiveness. Products with a higher SPF number provide greater protection against ultraviolet radiation. However in 1998, the Annual Meeting of the American Association for the Advancement of Science reported that some sunscreens advertising UVA and UVB protection do not provide adequate safety from UVA radiation and could give sun tanners a false sense of protection.
Furthermore, tanning oils or creams are usually applied thicker on some parts of skin than on others. This situation causes some parts of skin to get more UVA and UVB exposure than others. For this reason, improper application of tanning oils or creams may increase the occurrence of skin cancer and other skin diseases.
Furthermore, tanning oils or creams are usually applied thicker on some parts of skin than on others. This situation causes some parts of skin to get more UVA and UVB exposure than others. For this reason, improper application of tanning oils or creams may increase the occurrence of skin cancer and other skin diseases.
Melanotan 1 and melanotan II are two separate synthetic analogs of the naturally occurring peptide hormone alpha-melanocyte stimulating hormone (α-MSH) that have been shown to induce skin tanning through melanogenesis and in the case of melanotan I, reduce sun (UV) damage in preliminary studies and clinical trials. Melanotan II has the additional effect of increasing libido in both sexes and has been demonstrated to overcome both organic and psychogenic erectile dysfunction in trials. The first peptide unchanged and a derivative of the second are in development by pharmaceutical companies, but as of 2008 no melanotan I or II based compound has been approved for use by any governmental drug regulatory bodies outside of clinical trials. Unlicensed and untested melanotan products are sold through the Internet however, regulatory bodies have warned consumers they may be unsafe and ineffective.
