Sun tanning

A woman sunbathing

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A suntanned arm showing browner skin where it has been exposed. This pattern of tanning is often called a farmer's tan

Sun tanning describes a darkening of the skin (especially of fair-skinned individuals) in a natural physiological response stimulated by exposure to ultraviolet radiation from sunshine or from artificial sources such as a tanning bed. With excess exposure to ultraviolet, a sunburn can develop.

Cause and effect

Darkening of the skin is caused by an increased release of the pigment melanin into the skin's cells after exposure to ultraviolet radiation. Melanin is produced by cells called melanocytes and protects the body from absorbing an excess of solar radiation, which can be harmful. Depending on genetics, some people can darken quickly and deeply whereas others do not darken much at all.

The ultraviolet frequencies responsible for tanning are often divided into the UVA (315 to 400nm wavelength) and UVB (280 to 315nm wavelength) ranges. UVB waves have higher energy than UVA waves and are therefore more damaging and more carcinogenic.

UVB

• triggers creation and secretion of new melanin into the skin
• is thought to cause the formation of moles and some types of skin cancer (but not melanoma)
• causes skin aging (but at a far slower rate than UVA.)
• produces Vitamin D in human skin
• is more likely to cause a sunburn than UVA as a result of overexposure
• reduced by virtually all sunscreens in accordance with their SPF

UVA

• causes release of preexisting melanin from the melanocytes
• causes the melanin to combine with oxygen (oxidize), which creates the actual tan color in the skin
• seems to cause cancer less than UVB, but causes melanoma, a far more dangerous type of skin cancer than other types
• is blocked less than UVB by many sunscreens but is blocked to some degree by clothing
• is present more uniformly throughout the day, and throughout the seasons than UVB

Health benefits

The skin produces vitamin D in response to sun exposure (in particular, UVB waves in the 285nm to 287nm 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 occurred from melanoma or squamous cell carcinoma, so the overall effect of sun tanning might be beneficial. Another 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.

However 10 to 15 minutes of sun exposure two times per week will provide adequate vitamin D, while minimizing risks from UV exposure. Further, sun exposure and tanning will not produce vitamin D when the sun is too low in the sky.

Another effect of vitamin D deficiency is osteomalacia, which can result in bone pain, difficulty in weight bearing and sometimes fractures. This work has been updated in Grant et al. 2005 and Grant and Garland, 2006 In addition, it was reported that in Spain, risk of non-melanoma skin cancer is balanced by reduced risk of 16 types of cancer [Grant, 2006]

According to a 2007 research of Islam, Gauderman, Cozen, and Mack , sun exposure during childhood prevents multiple sclerosis later in life.

Ultraviolet radiation has other medical applications, in the treatment of skin conditions such as psoriasis and vitiligo. Sunshine is informally used as a short term way to treat or hide acne, but research shows that in the long term, acne worsens with sunlight exposure and safer treatments now exist (see phototherapy).

Cultural history

Sunbathing Russian girl on the Turkish beach

Culturally, a suntan may be regarded as attractive, although this is susceptible to the whims of fashion. In ancient Rome, women deliberately lightened their skin with lead based cosmetics. At the time of Shakespeare, before the industrial revolution, untanned skin signified higher status.

In Europe, during much of the 18th and 19th centuries, fair, freckleless skin was considered attractive, especially in women, since tanned skin was associated with manual labour such as on a farm or in the outdoor employ of a wealthier person. Having fair skin signified that one was wealthy enough to hire other people to do manual labour. In 18th-century France, members of the royal court emphasized this point by powdering their faces to look as white as possible. As labour patterns shifted during the early 20th century, with indoor work becoming the norm, tanned skin came to be seen as a credential for membership of the leisured classes. When famous fashion designer Coco Chanel accidentally acquired a dark tan during a vacation on the French Riviera in 1920s, she ignited a fad among Caucasians for tanned skin. By the 1960s, a tan's earlier social significance had been reversed and bronzed skin among Caucasians often signified social status, wealth and health, possibly for the opposite reason. Now that most jobs are done inside, tans among light-skinned people signify the wealth required to have the leisure time to acquire one.

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Sometimes tanning can be used for comedic purposes

Intentionally darkening one's skin did not become a socially desirable phenomenon in the West until the mid-20th century. For centuries, sharp divisions existed in most societies between the upper classes, whose members held positions of power and leisure indoors, and the commonfolk who typically led agrarian lives toiling outside. As a result, wealthier people tended to be fairer-skinned and this correlation made pale skin more desirable. Hence, the word "fair" came to mean "beautiful". The Industrial Revolution brought poor laborers and wealthy industrialists alike inside under the same roofs and this distinction began to evaporate. By the end of World War II, the economic boom the United States experienced gave middle class citizens more time and money to devote to leisurely pursuits. Vacations became standard practice and the advent of air travel made warmer, tropical destinations a more realistic possibility for average people. Tanned skin became associated not with a hard life of labor in the fields, but with swimming pools, backyard barbecues, dinner parties, and exotic vacations. In this context, tanned skin took on a feature of attractiveness as a signal of being well-traveled, cultured, and supposed evidence of leisure wealth. It also became a signal of health and strength as the bodybuilding and fitness industries increasingly promoted tanning to highlight muscle tone and definition.

In some other parts of the world, fair skin remains the standard of beauty. The geisha of Japan were renowned for their brilliant white painted faces, and the appeal of the bihaku (美白), or "beautiful white", ideal leads many Japanese women to avoid any form of tanning, and the color white is associated with purity and divinity in many Eastern religions. In post-colonial Africa and India, dark skin is heavily associated with a lower class status, and some people resort to skin bleaching to achieve a skin color they view as more socially acceptable.

Dressing for sun tanning

Women wearing monokinis sunbathing on a beach in Barcelona, Spain to avoid tan lines.

Many people choose to sun tan without clothes to maximize tanning coverage, maximizing health benefits of sun exposure, increasing the sensitory experience and reducing or eliminating tan lines caused by the contrast of exposed and unexposed tanned skin. While some are content to simply sun tan in the privacy of their own private property, some governmental agencies have responded to more demand for clothing-optional sun tanning in public spaces.

As an example, Englischer Garten in urban Munich has meadows where nude sun tanning is the norm. In Denmark, clothing-optional sun tanning is the default dress code on all beaches, with the exception of two[1]. In other areas of the world, clothing-free sun tanning could be met with citation or fines. Clothing-optional beaches (also known as naturist, nude or nudist beaches) and other areas where quiet use or traditional use is tolerated, generally allow for such opportunities without fear of legal harassment or penalty. Even more beaches allow topfree tanning for women. Some describe beaches where nudity or topfree tanning is tolerated to be "more European".[2]. Geographic areas in the US with warm to tropical climates with extensive beach fronts often cater to such tourist opportunities, e.g. Haulover Beach, Gunnison Beach, Black's Beach and Baker Beach.

TANNING SUCKS!!!

tanning is for nerds

See also

• Freckles
• Melanotan (Peptide based tanning)
• Skin cancer
• Skin whitening
• Slip-Slop-Slap
• Social nudity
• Sunless tanning
• Sun protective clothing
• Sunscreen
• Tanning bed

External links

• Make sure that the sunscreen you use has The Skincancer Foundation's Seal of Recommendation
• History of Suntanning
• BBC info page on tanning
• Calculate how long sunscreen protects you
• Research on the benefits of UV exposure
• The Truth about Tanning
• Benefits of the sun

Articles

• Grant, William B. (2002). An estimate of premature cancer mortality in the US due to inadequate doses of solar ultraviolet-B radiation. Cancer 94 (6), 1867–1875.
• Matsumura Y, Ananthaswamy HN (2004). Toxic effects of UV radiation on the skin. Toxicol. Appl. Pharmacol. 195 (3), 298-308.
• Hu S, et al. (2004). UV radiation and melanoma in US Hispanics & blacks. Arch Dermatol. 140 (7), 819-824.
• Bhatia, Suruchi, MD. , (2002). Increase of rickets in young tracked in Bay Area
• Over One Billion People May Suffer From Vitamin D Deficiency