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Sun tanning

Sun tanning or tanning is the process whereby skin color is darkened or tanned. It is most often a result of exposure to ultraviolet (UV) radiation from sunlight or from artificial sources, such as a tanning lamp found in indoor tanning beds. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. Some people use chemical products which can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning.

A visible tan line on a woman whose skin has been darkened by ultraviolet exposure, except where covered

Impact on skin health edit

Moderate exposure edit

 
A sun tanned arm showing browner skin where it has been exposed

Moderate exposure to direct sunlight contributes to the production of melanin and vitamin D by the body.

Excessive exposure edit

Excessive exposure to ultraviolet rays has negative health effects, including sunburn. Some people tan or sunburn more easily than others. This may be the result of different skin types and natural skin color, and these may be a result of genetics.[1][2] The term "tanning" has a cultural origin, arising from the color tan. Its origin lies in the Western culture of Europe when it became fashionable for young women to seek a less pale complexion (see Cultural history below).

Long-term edit

 
Photoaging of a woman

Excessive exposure may in the long-term increase the risk of skin cancer,[3] as well as depressed immune system function and accelerated aging of the skin.[4]

Tanning process edit

Melanin is a natural pigment produced by cells called melanocytes in a process called melanogenesis. Melanocytes produce two types of melanin: pheomelanin (red) and eumelanin (very dark brown). Melanin protects the body by absorbing ultraviolet radiation. Excessive UV radiation causes sunburn along with other direct and indirect DNA damage to the skin, and the body naturally combats and seeks to repair the damage and protect the skin by creating and releasing further melanin into the skin's cells. With the production of the melanin, the skin color darkens. The tanning process can be triggered by natural sunlight or by artificial UV radiation, which can be delivered in frequencies of UVA, UVB, or a combination of both.[5] The intensity is commonly measured by the UV Index.[6]

 
Cross-sectional view showing skin tone becoming darker due to the production of more melanin to overcome DNA damage caused by UV radiation

There are two different mechanisms involved in the production of a tan by UV exposure: Firstly, UVA radiation creates oxidative stress, which in turn oxidizes existing melanin and leads to rapid darkening of the melanin. UVA may also cause melanin to be redistributed (released from melanocytes where it is already stored), but its total quantity is unchanged. Skin darkening from UVA exposure does not lead to significantly increased production of melanin or protection against sunburn.[7] In the second process, triggered primarily by UVB, there is an increase in production of melanin (melanogenesis),[8] which is the body's reaction to direct DNA photodamage (formation of pyrimidine dimers) from UV radiation.[9] Melanogenesis leads to delayed tanning, and typically becomes visible two or three days after exposure.[8] The tan that is created by increased melanogenesis typically lasts for a few weeks or months, much longer than the tan that is caused by oxidation of existing melanin, and is also actually protective against UV skin damage and sunburn, rather than simply cosmetic. Typically, it can provide a modest Sun Protection Factor (SPF) of 3, meaning that tanned skin would tolerate up to 3 times the UV exposure as pale skin.[10] However, in order to cause true melanogenesis-tanning by means of UV exposure, some direct DNA photodamage must first be produced, and this requires UVB exposure (as present in natural sunlight, or sunlamps that produce UVB).[citation needed] The ultraviolet frequencies responsible for tanning are often divided into the UVA and UVB ranges.

UVA edit

Ultraviolet A (UVA) radiation is in the wavelength range 320 to 400 nm.[11] It is present more uniformly throughout the day, and throughout the year, than UVB. Most UVA is not blocked by the atmosphere's ozone layer. UVA causes the release of existing melanin from the melanocytes to combine with oxygen (oxidize) to create the actual tan color in the skin.[citation needed] UVA is blocked less than UVB by many sunscreens, but is blocked to some degree by clothing. UVA is known both to cause DNA damage and to be carcinogenic. However, it operates not by inducing direct DNA damage, but by producing reactive oxygen species which damage DNA indirectly. UVA (see above) induces a cosmetic tan but little extra melanin protection against sun damage, sun burn, or cancer.[citation needed]

UVB edit

Ultraviolet B (UVB) radiation is in the wavelength range 280 to 320 nm. Much of this band is blocked by the Earth's ozone layer, but some penetrates. UVB:

  • triggers the formation of CPD-DNA damage (direct DNA damage), which in turn induces an increased melanin production.[9]
  • is more likely to cause a sunburn than UVA as a result of overexposure. The mechanism for sunburn and increased melanogenesis is identical.[12] Both are caused by the direct DNA damage (formation of CPDs).
  • produces Vitamin D in human skin.
  • is reduced by virtually all sunscreens in accordance with their SPF.
  • is thought, but not proven, to cause the formation of moles and some types of skin cancer.
  • causes skin aging (but at a slower rate than UVA).[citation needed]
  • stimulates the production of new melanin, which leads to an increase in the dark-colored pigment within a few days.[13]

Tanning behavior of different skin colors edit

A person's natural skin color affects their reaction to exposure to sunlight. An individual's natural skin color can vary from a dark brown to a nearly colorless pigmentation, which may appear white. In 1975, Harvard dermatologist Thomas B. Fitzpatrick devised the Fitzpatrick scale which described the common tanning behavior of various skin types, as follows:[14][15]

Type Also called Sunburning Tanning behavior von Luschan scale
I Very light or pale Often Occasionally 1–5
II Light or light-skinned Usually Sometimes 6–10
III Light intermediate Rarely Usually 11–15
IV Dark intermediate Rarely Often 16–21
V Dark or "brown" type No Sometimes darkens 22–28
VI Very dark or "black" type No Naturally black-brown skin 29–36

Health aspects edit

 
Sunburn peeling
 
Disappearing sun tan, revealing the individual's naturally light-colored skin

The most common risk of exposure to ultraviolet radiation is sunburn, the speed and severity of which vary among individuals. This can be alleviated at least to some extent by the prior application of a suitable-strength sunscreen, which will also hinder the tanning process due to the blocking of UV light. Overexposure to ultraviolet radiation is known to cause skin cancer,[16] make skin age and wrinkle faster,[17] mutate DNA,[18] and impair the immune system.[19] Frequent tanning bed use triples the risk of developing melanoma, the deadliest form of skin cancer, according to a 2010 study. The study suggests that the melanoma risk is linked more closely to total exposure than it is to the age at which an individual first uses a tanning bed.[20] The International Agency for Research on Cancer places the use of tanning beds in the highest cancer risk category, describing them as carcinogenic to humans even if used as recommended.[citation needed] Frequent tanning also has behavioural reinforcing effects,[21] following UVA radiation epidermal keratinocytes synthesize POMC inducing the production of β-Endorphins which are opioid agonists. An opioid blockade will also then cause withdrawal signs after habitual UV exposure leading to many tanners meeting the DSM-IV criteria for addiction.[22] Several organizations, such as the World Health Organization (WHO), the American Cancer Society and the US Surgeon General have issued guidelines warning about sun tanning and UV radiation exposure, either from the sun or from indoor tanning.[23][24][25] Production of vitamin D is essential for human health. Moderate exposure (avoiding sunburn) to UV radiation provides benefits such as increased vitamin D, as well as other possible benefits that are still being studied.[26] Several tanning activators have used different forms of psoralen, which are known to be photocarcinogenic.[27][28][29] Health authorities have banned psoralen since July 1996.[30]

Cultural history edit

 
La promenade (1875) by Claude Monet. At that time in the West, the upper social class used parasols, long sleeves and hats to avoid sunlight's tanning effects.

In the United States and Western Europe before the 1920s, tanned skin was associated with the lower classes because they worked outdoors and were exposed to the sunlight. Parasols and long sleeves were typically worn, even at beaches.[31] By the 1920s, however, a cultural transformation took place, and tan skin became the ideal.[31]

By the early 20th century, therapeutic benefits of sunlight were advertised to the public.[32] In 1903, Niels Finsen was awarded the Nobel Prize in Medicine for his “Finsen Light Therapy”.[33] The therapy was a cure for diseases such as lupus vulgaris and rickets. Vitamin D deficiency was found to be a cause of rickets, and exposure to sunlight would allow vitamin D to be produced in a person. Therefore, sunlight exposure was a remedy to curing several diseases, especially rickets.

In 1910 a scientific expedition went to the island of Tenerife to test the wider health benefits of "heliotherapy",[34] and by 1913 "sunbathing" was referred to as a desirable activity for the leisured class.[35] Shortly thereafter, in the 1920s, fashion-designer Coco Chanel accidentally got sunburnt while visiting the French Riviera. When she arrived home, she arrived with a sun tan and her fans apparently liked the look and started to adopt darker skin tones themselves. Tanned skin became a trend partly because of Coco's status and the longing for her lifestyle by other members of society. In addition, Parisians fell in love with Josephine Baker, a "caramel-skinned" singer in Paris, and idolized her darker skin. These two women were leading figures of the transformation that tan skin underwent, in which it became perceived as fashionable, healthy, and luxurious.[36][37][38] Jean Patou capitalized on the new tanning fad, launching the first sun tan oil "Huile de Chaldee" in 1927.[39] Just before the 1930s, sunlight therapy became a popularly subscribed cure for almost every ailment from simple fatigue to tuberculosis. In the 1940s, advertisements started appearing in women's magazines which encouraged sunbathing. At the same time, swimsuits' skin coverage began decreasing, with the bikini radically changing swimsuit style after it made its appearance in 1946. In the 1950s, many people used baby oil as a method to increase tanning.

Coppertone, in 1953, marketed its sunscreen with a drawing of a young girl and her cocker spaniel tugging on her bathing suit bottom, revealing her bare bottom and tan line; this advertisement was modified around the turn of the 21st century and now shows a little girl wearing a one-piece bathing suit or shorts.[40] In the latter part of the 1950s, silver metallic reflectors were common to enhance one's tan.[41] In 1962, sunscreen commenced to be SPF rated, although SPF labeling in the US was not standardized by the FDA until 1978. In the 1970s, Mattel introduced Malibu Barbie, which had tanned skin and further popularized sun tanning among women.[42][43]

In 1978, both sunscreen with an SPF 15 rating as well as tanning beds first appeared. In 2007, there were an estimated 50,000 outlets for indoor tanning; it was a five-billion-dollar industry in the United States,[44] and had spawned an auxiliary industry for indoor tanning lotions including bronzers, intensifiers, and accelerators. Since then, the indoor tanning industry has become more constrained by health regulations.[45] In China, darker skin is still considered by many to be the mark of the lower classes. As recently as 2012, in some parts of China, ski masks were becoming popular items to wear at the beach in order to protect the wearer's face from the effects of sunlight.[46] A 1969 innovation is tan-through swimwear, which uses fabric perforated with thousands of micro holes that are nearly invisible to the naked eye, but which transmit enough sunlight to approach an all-over tan, especially if the fabric is stretched taut. Tan-through swimwear typically allows more than one-third of UV rays to pass through (equivalent to SPF 3 or less), and an application of sunscreen even to the covered area is recommended.[47][48][49]

Sunless tanning edit

 
A tanning bed emits UV radiation.

To avoid exposure to UVB and UVA rays, or in seasons without strong sunshine, some people take alternative steps to appear with darkened skin. They may use sunless tanning (also known as self-tanners); stainers which are based on dihydroxyacetone (DHA);[50] or cosmetics such as bronzers.[citation needed] Many sunless tanning products are available in the form of darkening creams, gels, lotions, and sprays that are self-applied on the skin. There is also a professional spray-on tanning option or “tanning booth” that is offered by spas, salons, and tanning businesses.[51] Spray tanning does not involve a color being sprayed on the body, instead it uses a colorless chemical which reacts with proteins in the top layer of the skin, resulting in a brown color.[citation needed]

See also edit

References edit

  1. ^ Marshall, Jessica. "Gene behind tanning comes out of hiding". New Scientist. from the original on 25 November 2020. Retrieved 28 October 2020.
  2. ^ "Scientists find why some people tan and some people burn". The Independent. 8 May 2018. Archived from the original on 25 May 2022.
  3. ^ "Ultraviolet (UV) Radiation". from the original on 6 September 2015. Retrieved 27 August 2015.
  4. ^ Amaro-Ortiz, Alexandra; Yan, Betty; D’Orazio, John A. (15 May 2014). "Ultraviolet Radiation, Aging and the Skin: Prevention of Damage by Topical cAMP Manipulation". Molecules. 19 (5): 6202–6219. doi:10.3390/molecules19056202. ISSN 1420-3049. PMC 4344124. PMID 24838074.
  5. ^ Garone, Michael; Howard, John; Fabrikant, Jordan (February 2015). "A Review of Common Tanning Methods". The Journal of Clinical and Aesthetic Dermatology. 8 (2): 43–47. ISSN 1941-2789. PMC 4345932. PMID 25741402.
  6. ^ Encyclopædia Britannica almanac 2010. Chicago: Encyclopædia Britannica. 2009. ISBN 978-1615353293.
  7. ^ Miyamura Y; Coelho SG; Schlenz K; et al. (February 2011). "The deceptive nature of UVA tanning versus the modest protective effects of UVB tanning on human skin". Pigment Cell & Melanoma Research. 24 (1): 136–147. doi:10.1111/j.1755-148X.2010.00764.x. PMC 3021652. PMID 20979596.
  8. ^ a b Amy Thorlin (5 February 2006). . Lookingfit.com. Archived from the original on 22 July 2009. Retrieved 15 April 2015.
  9. ^ a b Nita Agar; Antony R. Young (2005). "Review: Melanogenesis: a photoprotective response to DNA damage?". Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis. 571 (1–2): 121–132. doi:10.1016/j.mrfmmm.2004.11.016. PMID 15748643.
  10. ^ "The Surgeon General's Call to Action to Prevent Skin Cancer" (PDF). U.S. Department of Health and Human Services. 2014. p. 20. (PDF) from the original on 26 November 2014. A UVB-induced tan provides minimal sun protection, equivalent to an SPF of about 3.
  11. ^ "ISO 21348 Definitions of Solar Irradiance Spectral Categories" (PDF). (PDF) from the original on 29 October 2013.
  12. ^ John A. Parrish; Kurt F. Jaenicke; R. Rox Anderson (1982). "Erythema And Melanogenesis Action Spectra Of Normal Human Skin". Photochemistry and Photobiology. 36 (2): 187–191. doi:10.1111/j.1751-1097.1982.tb04362.x. PMID 7122713. S2CID 38940583.
  13. ^ "The known health effects of UV". WHO. 1 December 2010. from the original on 4 August 2012. Retrieved 1 August 2012.
  14. ^ Fitzpatrick TB: Soleil et peau [Sun and skin]. Journal de Médecine Esthétique 1975; 2:33-34
  15. ^ Weller, R; J Hunter; J Savin; M Dahl (2008). Clinical Dermatology (4th ed.). Malden, Massachusetts, USA: Blackwell Publishing. p. 268. ISBN 978-1-4051-4663-0.
  16. ^ . ntp.niehs.nih.gov. Archived from the original on 16 December 2016. Retrieved 13 December 2016.
  17. ^ Fisher GJ, Wang ZQ, Datta SC, Varani J, Kang S, Voorhees JJ (November 1997). "Pathophysiology of premature skin aging induced by ultraviolet light". N. Engl. J. Med. 337 (20): 1419–28. doi:10.1056/NEJM199711133372003. PMID 9358139.
  18. ^ Sinha RP, Häder DP (April 2002). "UV-induced DNA damage and repair: a review". Photochem. Photobiol. Sci. 1 (4): 225–36. doi:10.1039/B201230H. PMID 12661961.
  19. ^ Baadsgaard O (January 1991). "In vivo ultraviolet irradiation of human skin results in profound perturbation of the immune system. Relevance to ultraviolet-induced skin cancer". Arch Dermatol. 127 (1): 99–109. doi:10.1001/archderm.1991.01680010109019. PMID 1824747.
  20. ^ Peeples, Lynne. Study: Frequent tanning-bed use triples melanoma risk. 30 May 2010 at the Wayback Machine CNN, 27 May 2010.
  21. ^ Kaur, Mandeep; Liguori, Anthony; Lang, Wei; Rapp, Stephen R.; Fleischer, Alan B.; Feldman, Steven R. (1 April 2006). "Induction of withdrawal-like symptoms in a small randomized, controlled trial of opioid blockade in frequent tanners". Journal of the American Academy of Dermatology. 54 (4): 709–711. doi:10.1016/j.jaad.2005.11.1059. ISSN 0190-9622. PMID 16546596.
  22. ^ "Side effects of naltrexone observed in frequent tanners: Could frequent tanners have ultraviolet-induced high opioid levels?". pdfslide.us. from the original on 7 March 2022. Retrieved 7 March 2022.
  23. ^ Sunscreens - IARC Handbook of Cancer Prevention Volume 5. ISBN 9789283230052. from the original on 11 February 2017. Retrieved 9 February 2017. {{cite book}}: |website= ignored (help)
  24. ^ "Skin Cancer". www.cancer.org. from the original on 17 January 2017. Retrieved 9 February 2017.
  25. ^ General, Office of the Surgeon. "The Surgeon General's Call to Action to Prevent Skin Cancer". www.surgeongeneral.gov. from the original on 9 February 2017. Retrieved 9 February 2017.
  26. ^ Baggerly, Carole A.; Cuomo, Raphael E.; French, Christine B.; Garland, Cedric F.; Gorham, Edward D.; Grant, William B.; Heaney, Robert P.; Holick, Michael F.; Hollis, Bruce W.; McDonnell, Sharon L.; Pittaway, Mary; Seaton, Paul; Wagner, Carol L.; Wunsch, Alexander (22 June 2015). "Sunlight and Vitamin D: Necessary for Public Health". Journal of the American College of Nutrition. 34 (4): 359–365. doi:10.1080/07315724.2015.1039866. PMC 4536937. PMID 26098394.
  27. ^ Ashwood-Smith MJ. (1979). "Possible cancer hazard associated with 5-methoxypsoralen in sun tan preparations". BMJ. 2 (6198): 1144. doi:10.1136/bmj.2.6198.1144-b. PMC 1596980. PMID 519338.
  28. ^ M. J. Ashwood-Smith; G. A. Poulton; M. Barker; M. Mildenberger E. (1980). "5-Methoxypsoralen, an ingredient in several sun tan preparations, has lethal, mutagenic and clastogenic properties". Nature. 285 (5): 407–409. Bibcode:1980Natur.285..407A. doi:10.1038/285407a0. PMID 6991953. S2CID 4345680.
  29. ^ Zajdela F, Bisagni E (1981). "5-Methoxypsoralen, the melanogenic additive in sun-tan preparations, is tumorigenic in mice exposed to 365 nm UV radiation". Carcinogenesis. 2 (2): 121–7. doi:10.1093/carcin/2.2.121. PMID 7273295.
  30. ^ Autier P.; Dore J.-F.; Cesarini J.-P. (1997). "Should subjects who used psoralen sun tan activators be screened for melanoma?". Annals of Oncology. 8 (5): 435–437. doi:10.1023/A:1008205513771. PMID 9233521.
  31. ^ a b Singer, Merrill; Hans Baer (28 July 2008). Killer Commodities: Public Health and the Corporate Production of Harm. AltaMira Press. p. 151. ISBN 978-0-7591-0979-7. Retrieved 11 September 2009. Harris investigated the history of the parasol... everywhere ordinary people were forbidden to protect themselves with such devices "pallid skin became a marker of upper-class status". At the beginning of the 20th Century, in the United States, lighter-skinned people avoided the sun. ... Tanned skin was considered lower class...But by the 1920s, a cultural transformation in favor of sun tanning took place.
  32. ^ "The Times". 25 August 1900: 1: An advertisement for a 'German Bath In Scotland' offers 'For Health and Pleasure...Pure Air and Sun Baths...'. {{cite journal}}: Cite journal requires |journal= (help)
  33. ^ "All Nobel Laureates in Physiology or Medicine". Nobel Media. from the original on 12 May 2015. Retrieved 29 April 2015.
  34. ^ "The Times". 12 March 1910: 12. {{cite journal}}: Cite journal requires |journal= (help)
  35. ^ "The Times". 4 September 1913: 6. {{cite journal}}: Cite journal requires |journal= (help):Describing a visit by the Prince of Wales to the pretty town of Sigmaringen the reporter says: ‘The Castle possesses many delightful terraces which could be adapted for sunbathing.’
  36. ^ Hanson, Peter G. (22 June 2009). . The Effects of Aging, Health and Stress on Your Face. FaceMaster. Archived from the original on 23 April 2012.{{cite web}}: CS1 maint: unfit URL (link)
  37. ^ . Magic Bullets - Chemistry vs. Cancer. The Chemical Heritage Foundation. 2001. Archived from the original on 20 June 2010. By the 1920s, the therapeutic effect of the sun was widely promoted, and two well-publicized French personalities gave "tanning" a fashion boost. Coco Chanel, of designer fame, returned to Paris after a cruise on the Duke of Westminster's yacht with a tan that became all the rage. And the natural caramel skin color of singer Josephine Baker made women all over the world try to emulate her skin tone.{{cite web}}: CS1 maint: unfit URL (link)
  38. ^ Koskoff, Sharon (28 May 2007). Art Deco of the Palm Beaches. Arcadia Publishing. p. 2. ISBN 978-0-7385-4415-1. Retrieved 11 September 2009. In 1920s France, the caramel-skinned entertainer Josephine Baker became a Parisian idol. Concurrently, fashion designer Coco Chanel was "bronzed" while cruising on a yacht. A winter tan became a symbol of the leisure class and showed you could afford to travel to exotic climates.
  39. ^ Steele, Valerie, ed. (2010). The Berg Companion to Fashion. Berg. p. 554. ISBN 978-1847885630.
  40. ^ . www.coppertone.com. Archived from the original on 26 October 2016. Retrieved 1 May 2018.
  41. ^ Campo, Riku (31 August 2010). Best in Beauty: An Ultimate Guide to Makeup and Skincare Techniques, Tools, and Products. Simon and Schuster. p. 185. ISBN 978-1-4391-5585-1.
  42. ^ Heckman, Carolyn J.; Manne, Sharon L. (15 September 2011). Shedding Light on Indoor Tanning. Springer Science & Business Media. p. 20. ISBN 978-94-007-2048-0.
  43. ^ Jablonski, Nina G. (27 September 2012). Living Color: The Biological and Social Meaning of Skin Color. University of California Press. p. 185. ISBN 978-0-520-25153-3.
  44. ^ Wright, Dan (16 August 2007). "Working The Tan". The Daily News-Record. Harrisonburg, Virginia. Archived from the original on 20 April 2010. Retrieved 11 September 2009. The tanning industry has grown about 25 percent over the past six years, according to the Indoor Tanning Association. In the United States, about 25,000 free-standing tanning salons employ 160,000 people and generate more than $5 billion in annual revenue, the association said.
  45. ^ Clark, Patrick (5 October 2016). "Twilight of the Tanning Salons". Bloomberg News. from the original on 10 October 2016. Retrieved 9 October 2016.
  46. ^ Levin, Dan (3 August 2012). "Beach Essentials in China: Flip-Flops, a Towel and a Ski Mask". The New York Times. from the original on 5 August 2012. Retrieved 5 August 2012.
  47. ^ Taylor, Angela (17 October 1969). "Tan-Through Fabric Lets Sun Shine In". The New York Times. p. 55. from the original on 12 October 2013. Retrieved 30 November 2014.
  48. ^ . Sports Illustrated. 1 September 1969. Archived from the original on 12 October 2013. permits 40% of the sun's ultraviolet rays{{cite news}}: CS1 maint: unfit URL (link)
  49. ^ "Tan-tastic bikini that lets rays shine through". Daily Express. 30 May 2009. from the original on 17 October 2014. Retrieved 17 September 2014. 80 per cent of UV rays... a stretchy yarn described as 'a chicken wire mesh material'
  50. ^ "Dihydroxyacetone". from the original on 28 July 2010. Retrieved 6 July 2010.
  51. ^ "Sunless tanning: A safe alternative to sunbathing". from the original on 16 February 2010. Retrieved 6 July 2010.

External links edit

  • Aim at Melanoma
  • Information on tanning from The Skin Cancer Foundation 7 December 2011 at the Wayback Machine
  • Research on the benefits of UV exposure
  • Melanoma Research Alliance

tanning, sunbather, redirects, here, 2013, album, deafheaven, sunbather, album, tanning, process, whereby, skin, color, darkened, tanned, most, often, result, exposure, ultraviolet, radiation, from, sunlight, from, artificial, sources, such, tanning, lamp, fou. Sunbather redirects here For the 2013 album by Deafheaven see Sunbather album Sun tanning or tanning is the process whereby skin color is darkened or tanned It is most often a result of exposure to ultraviolet UV radiation from sunlight or from artificial sources such as a tanning lamp found in indoor tanning beds People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing Some people use chemical products which can produce a tanning effect without exposure to ultraviolet radiation known as sunless tanning A visible tan line on a woman whose skin has been darkened by ultraviolet exposure except where covered Contents 1 Impact on skin health 1 1 Moderate exposure 1 2 Excessive exposure 1 2 1 Long term 2 Tanning process 2 1 UVA 2 2 UVB 3 Tanning behavior of different skin colors 4 Health aspects 5 Cultural history 6 Sunless tanning 7 See also 8 References 9 External linksImpact on skin health editModerate exposure edit nbsp A sun tanned arm showing browner skin where it has been exposedModerate exposure to direct sunlight contributes to the production of melanin and vitamin D by the body Excessive exposure edit Excessive exposure to ultraviolet rays has negative health effects including sunburn Some people tan or sunburn more easily than others This may be the result of different skin types and natural skin color and these may be a result of genetics 1 2 The term tanning has a cultural origin arising from the color tan Its origin lies in the Western culture of Europe when it became fashionable for young women to seek a less pale complexion see Cultural history below Long term edit nbsp Photoaging of a womanExcessive exposure may in the long term increase the risk of skin cancer 3 as well as depressed immune system function and accelerated aging of the skin 4 Tanning process editMelanin is a natural pigment produced by cells called melanocytes in a process called melanogenesis Melanocytes produce two types of melanin pheomelanin red and eumelanin very dark brown Melanin protects the body by absorbing ultraviolet radiation Excessive UV radiation causes sunburn along with other direct and indirect DNA damage to the skin and the body naturally combats and seeks to repair the damage and protect the skin by creating and releasing further melanin into the skin s cells With the production of the melanin the skin color darkens The tanning process can be triggered by natural sunlight or by artificial UV radiation which can be delivered in frequencies of UVA UVB or a combination of both 5 The intensity is commonly measured by the UV Index 6 nbsp Cross sectional view showing skin tone becoming darker due to the production of more melanin to overcome DNA damage caused by UV radiationThere are two different mechanisms involved in the production of a tan by UV exposure Firstly UVA radiation creates oxidative stress which in turn oxidizes existing melanin and leads to rapid darkening of the melanin UVA may also cause melanin to be redistributed released from melanocytes where it is already stored but its total quantity is unchanged Skin darkening from UVA exposure does not lead to significantly increased production of melanin or protection against sunburn 7 In the second process triggered primarily by UVB there is an increase in production of melanin melanogenesis 8 which is the body s reaction to direct DNA photodamage formation of pyrimidine dimers from UV radiation 9 Melanogenesis leads to delayed tanning and typically becomes visible two or three days after exposure 8 The tan that is created by increased melanogenesis typically lasts for a few weeks or months much longer than the tan that is caused by oxidation of existing melanin and is also actually protective against UV skin damage and sunburn rather than simply cosmetic Typically it can provide a modest Sun Protection Factor SPF of 3 meaning that tanned skin would tolerate up to 3 times the UV exposure as pale skin 10 However in order to cause true melanogenesis tanning by means of UV exposure some direct DNA photodamage must first be produced and this requires UVB exposure as present in natural sunlight or sunlamps that produce UVB citation needed The ultraviolet frequencies responsible for tanning are often divided into the UVA and UVB ranges UVA edit Ultraviolet A UVA radiation is in the wavelength range 320 to 400 nm 11 It is present more uniformly throughout the day and throughout the year than UVB Most UVA is not blocked by the atmosphere s ozone layer UVA causes the release of existing melanin from the melanocytes to combine with oxygen oxidize to create the actual tan color in the skin citation needed UVA is blocked less than UVB by many sunscreens but is blocked to some degree by clothing UVA is known both to cause DNA damage and to be carcinogenic However it operates not by inducing direct DNA damage but by producing reactive oxygen species which damage DNA indirectly UVA see above induces a cosmetic tan but little extra melanin protection against sun damage sun burn or cancer citation needed UVB edit Ultraviolet B UVB radiation is in the wavelength range 280 to 320 nm Much of this band is blocked by the Earth s ozone layer but some penetrates UVB triggers the formation of CPD DNA damage direct DNA damage which in turn induces an increased melanin production 9 is more likely to cause a sunburn than UVA as a result of overexposure The mechanism for sunburn and increased melanogenesis is identical 12 Both are caused by the direct DNA damage formation of CPDs produces Vitamin D in human skin is reduced by virtually all sunscreens in accordance with their SPF is thought but not proven to cause the formation of moles and some types of skin cancer causes skin aging but at a slower rate than UVA citation needed stimulates the production of new melanin which leads to an increase in the dark colored pigment within a few days 13 Tanning behavior of different skin colors editA person s natural skin color affects their reaction to exposure to sunlight An individual s natural skin color can vary from a dark brown to a nearly colorless pigmentation which may appear white In 1975 Harvard dermatologist Thomas B Fitzpatrick devised the Fitzpatrick scale which described the common tanning behavior of various skin types as follows 14 15 Type Also called Sunburning Tanning behavior von Luschan scaleI Very light or pale Often Occasionally 1 5II Light or light skinned Usually Sometimes 6 10III Light intermediate Rarely Usually 11 15IV Dark intermediate Rarely Often 16 21V Dark or brown type No Sometimes darkens 22 28VI Very dark or black type No Naturally black brown skin 29 36Health aspects editMain article Health effects of sunlight exposure nbsp Sunburn peeling nbsp Disappearing sun tan revealing the individual s naturally light colored skinThe most common risk of exposure to ultraviolet radiation is sunburn the speed and severity of which vary among individuals This can be alleviated at least to some extent by the prior application of a suitable strength sunscreen which will also hinder the tanning process due to the blocking of UV light Overexposure to ultraviolet radiation is known to cause skin cancer 16 make skin age and wrinkle faster 17 mutate DNA 18 and impair the immune system 19 Frequent tanning bed use triples the risk of developing melanoma the deadliest form of skin cancer according to a 2010 study The study suggests that the melanoma risk is linked more closely to total exposure than it is to the age at which an individual first uses a tanning bed 20 The International Agency for Research on Cancer places the use of tanning beds in the highest cancer risk category describing them as carcinogenic to humans even if used as recommended citation needed Frequent tanning also has behavioural reinforcing effects 21 following UVA radiation epidermal keratinocytes synthesize POMC inducing the production of b Endorphins which are opioid agonists An opioid blockade will also then cause withdrawal signs after habitual UV exposure leading to many tanners meeting the DSM IV criteria for addiction 22 Several organizations such as the World Health Organization WHO the American Cancer Society and the US Surgeon General have issued guidelines warning about sun tanning and UV radiation exposure either from the sun or from indoor tanning 23 24 25 Production of vitamin D is essential for human health Moderate exposure avoiding sunburn to UV radiation provides benefits such as increased vitamin D as well as other possible benefits that are still being studied 26 Several tanning activators have used different forms of psoralen which are known to be photocarcinogenic 27 28 29 Health authorities have banned psoralen since July 1996 30 Cultural history editSee also Social status colorism and racism nbsp La promenade 1875 by Claude Monet At that time in the West the upper social class used parasols long sleeves and hats to avoid sunlight s tanning effects In the United States and Western Europe before the 1920s tanned skin was associated with the lower classes because they worked outdoors and were exposed to the sunlight Parasols and long sleeves were typically worn even at beaches 31 By the 1920s however a cultural transformation took place and tan skin became the ideal 31 By the early 20th century therapeutic benefits of sunlight were advertised to the public 32 In 1903 Niels Finsen was awarded the Nobel Prize in Medicine for his Finsen Light Therapy 33 The therapy was a cure for diseases such as lupus vulgaris and rickets Vitamin D deficiency was found to be a cause of rickets and exposure to sunlight would allow vitamin D to be produced in a person Therefore sunlight exposure was a remedy to curing several diseases especially rickets In 1910 a scientific expedition went to the island of Tenerife to test the wider health benefits of heliotherapy 34 and by 1913 sunbathing was referred to as a desirable activity for the leisured class 35 Shortly thereafter in the 1920s fashion designer Coco Chanel accidentally got sunburnt while visiting the French Riviera When she arrived home she arrived with a sun tan and her fans apparently liked the look and started to adopt darker skin tones themselves Tanned skin became a trend partly because of Coco s status and the longing for her lifestyle by other members of society In addition Parisians fell in love with Josephine Baker a caramel skinned singer in Paris and idolized her darker skin These two women were leading figures of the transformation that tan skin underwent in which it became perceived as fashionable healthy and luxurious 36 37 38 Jean Patou capitalized on the new tanning fad launching the first sun tan oil Huile de Chaldee in 1927 39 Just before the 1930s sunlight therapy became a popularly subscribed cure for almost every ailment from simple fatigue to tuberculosis In the 1940s advertisements started appearing in women s magazines which encouraged sunbathing At the same time swimsuits skin coverage began decreasing with the bikini radically changing swimsuit style after it made its appearance in 1946 In the 1950s many people used baby oil as a method to increase tanning Coppertone in 1953 marketed its sunscreen with a drawing of a young girl and her cocker spaniel tugging on her bathing suit bottom revealing her bare bottom and tan line this advertisement was modified around the turn of the 21st century and now shows a little girl wearing a one piece bathing suit or shorts 40 In the latter part of the 1950s silver metallic reflectors were common to enhance one s tan 41 In 1962 sunscreen commenced to be SPF rated although SPF labeling in the US was not standardized by the FDA until 1978 In the 1970s Mattel introduced Malibu Barbie which had tanned skin and further popularized sun tanning among women 42 43 In 1978 both sunscreen with an SPF 15 rating as well as tanning beds first appeared In 2007 there were an estimated 50 000 outlets for indoor tanning it was a five billion dollar industry in the United States 44 and had spawned an auxiliary industry for indoor tanning lotions including bronzers intensifiers and accelerators Since then the indoor tanning industry has become more constrained by health regulations 45 In China darker skin is still considered by many to be the mark of the lower classes As recently as 2012 in some parts of China ski masks were becoming popular items to wear at the beach in order to protect the wearer s face from the effects of sunlight 46 A 1969 innovation is tan through swimwear which uses fabric perforated with thousands of micro holes that are nearly invisible to the naked eye but which transmit enough sunlight to approach an all over tan especially if the fabric is stretched taut Tan through swimwear typically allows more than one third of UV rays to pass through equivalent to SPF 3 or less and an application of sunscreen even to the covered area is recommended 47 48 49 Sunless tanning editMain article Sunless tanning nbsp A tanning bed emits UV radiation To avoid exposure to UVB and UVA rays or in seasons without strong sunshine some people take alternative steps to appear with darkened skin They may use sunless tanning also known as self tanners stainers which are based on dihydroxyacetone DHA 50 or cosmetics such as bronzers citation needed Many sunless tanning products are available in the form of darkening creams gels lotions and sprays that are self applied on the skin There is also a professional spray on tanning option or tanning booth that is offered by spas salons and tanning businesses 51 Spray tanning does not involve a color being sprayed on the body instead it uses a colorless chemical which reacts with proteins in the top layer of the skin resulting in a brown color citation needed See also editSunburn Sunning Indoor tanning Perineum sunning Skin whiteningReferences edit Marshall Jessica Gene behind tanning comes out of hiding New Scientist Archived from the original on 25 November 2020 Retrieved 28 October 2020 Scientists find why some people tan and some people burn The Independent 8 May 2018 Archived from the original on 25 May 2022 Ultraviolet UV Radiation Archived from the original on 6 September 2015 Retrieved 27 August 2015 Amaro Ortiz Alexandra Yan Betty D Orazio John A 15 May 2014 Ultraviolet Radiation Aging and the Skin Prevention of Damage by Topical cAMP Manipulation Molecules 19 5 6202 6219 doi 10 3390 molecules19056202 ISSN 1420 3049 PMC 4344124 PMID 24838074 Garone Michael Howard John Fabrikant Jordan February 2015 A Review of Common Tanning Methods The Journal of Clinical and Aesthetic Dermatology 8 2 43 47 ISSN 1941 2789 PMC 4345932 PMID 25741402 Encyclopaedia Britannica almanac 2010 Chicago Encyclopaedia Britannica 2009 ISBN 978 1615353293 Miyamura Y Coelho SG Schlenz K et al February 2011 The deceptive nature of UVA tanning versus the modest protective effects of UVB tanning on human skin Pigment Cell amp Melanoma Research 24 1 136 147 doi 10 1111 j 1755 148X 2010 00764 x PMC 3021652 PMID 20979596 a b Amy Thorlin 5 February 2006 The Tanning Process Lookingfit com Archived from the original on 22 July 2009 Retrieved 15 April 2015 a b Nita Agar Antony R Young 2005 Review Melanogenesis a photoprotective response to DNA damage Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis 571 1 2 121 132 doi 10 1016 j mrfmmm 2004 11 016 PMID 15748643 The Surgeon General s Call to Action to Prevent Skin Cancer PDF U S Department of Health and Human Services 2014 p 20 Archived PDF from the original on 26 November 2014 A UVB induced tan provides minimal sun protection equivalent to an SPF of about 3 ISO 21348 Definitions of Solar Irradiance Spectral Categories PDF Archived PDF from the original on 29 October 2013 John A Parrish Kurt F Jaenicke R Rox Anderson 1982 Erythema And Melanogenesis Action Spectra Of Normal Human Skin Photochemistry and Photobiology 36 2 187 191 doi 10 1111 j 1751 1097 1982 tb04362 x PMID 7122713 S2CID 38940583 The known health effects of UV WHO 1 December 2010 Archived from the original on 4 August 2012 Retrieved 1 August 2012 Fitzpatrick TB Soleil et peau Sun and skin Journal de Medecine Esthetique 1975 2 33 34 Weller R J Hunter J Savin M Dahl 2008 Clinical Dermatology 4th ed Malden Massachusetts USA Blackwell Publishing p 268 ISBN 978 1 4051 4663 0 Reviewed Substances ntp niehs nih gov Archived from the original on 16 December 2016 Retrieved 13 December 2016 Fisher GJ Wang ZQ Datta SC Varani J Kang S Voorhees JJ November 1997 Pathophysiology of premature skin aging induced by ultraviolet light N Engl J Med 337 20 1419 28 doi 10 1056 NEJM199711133372003 PMID 9358139 Sinha RP Hader DP April 2002 UV induced DNA damage and repair a review Photochem Photobiol Sci 1 4 225 36 doi 10 1039 B201230H PMID 12661961 Baadsgaard O January 1991 In vivo ultraviolet irradiation of human skin results in profound perturbation of the immune system Relevance to ultraviolet induced skin cancer Arch Dermatol 127 1 99 109 doi 10 1001 archderm 1991 01680010109019 PMID 1824747 Peeples Lynne Study Frequent tanning bed use triples melanoma risk Archived 30 May 2010 at the Wayback Machine CNN 27 May 2010 Kaur Mandeep Liguori Anthony Lang Wei Rapp Stephen R Fleischer Alan B Feldman Steven R 1 April 2006 Induction of withdrawal like symptoms in a small randomized controlled trial of opioid blockade in frequent tanners Journal of the American Academy of Dermatology 54 4 709 711 doi 10 1016 j jaad 2005 11 1059 ISSN 0190 9622 PMID 16546596 Side effects of naltrexone observed in frequent tanners Could frequent tanners have ultraviolet induced high opioid levels pdfslide us Archived from the original on 7 March 2022 Retrieved 7 March 2022 Sunscreens IARC Handbook of Cancer Prevention Volume 5 ISBN 9789283230052 Archived from the original on 11 February 2017 Retrieved 9 February 2017 a href Template Cite book html title Template Cite book cite book a website ignored help Skin Cancer www cancer org Archived from the original on 17 January 2017 Retrieved 9 February 2017 General Office of the Surgeon The Surgeon General s Call to Action to Prevent Skin Cancer www surgeongeneral gov Archived from the original on 9 February 2017 Retrieved 9 February 2017 Baggerly Carole A Cuomo Raphael E French Christine B Garland Cedric F Gorham Edward D Grant William B Heaney Robert P Holick Michael F Hollis Bruce W McDonnell Sharon L Pittaway Mary Seaton Paul Wagner Carol L Wunsch Alexander 22 June 2015 Sunlight and Vitamin D Necessary for Public Health Journal of the American College of Nutrition 34 4 359 365 doi 10 1080 07315724 2015 1039866 PMC 4536937 PMID 26098394 Ashwood Smith MJ 1979 Possible cancer hazard associated with 5 methoxypsoralen in sun tan preparations BMJ 2 6198 1144 doi 10 1136 bmj 2 6198 1144 b PMC 1596980 PMID 519338 M J Ashwood Smith G A Poulton M Barker M Mildenberger E 1980 5 Methoxypsoralen an ingredient in several sun tan preparations has lethal mutagenic and clastogenic properties Nature 285 5 407 409 Bibcode 1980Natur 285 407A doi 10 1038 285407a0 PMID 6991953 S2CID 4345680 Zajdela F Bisagni E 1981 5 Methoxypsoralen the melanogenic additive in sun tan preparations is tumorigenic in mice exposed to 365 nm UV radiation Carcinogenesis 2 2 121 7 doi 10 1093 carcin 2 2 121 PMID 7273295 Autier P Dore J F Cesarini J P 1997 Should subjects who used psoralen sun tan activators be screened for melanoma Annals of Oncology 8 5 435 437 doi 10 1023 A 1008205513771 PMID 9233521 a b Singer Merrill Hans Baer 28 July 2008 Killer Commodities Public Health and the Corporate Production of Harm AltaMira Press p 151 ISBN 978 0 7591 0979 7 Retrieved 11 September 2009 Harris investigated the history of the parasol everywhere ordinary people were forbidden to protect themselves with such devices pallid skin became a marker of upper class status At the beginning of the 20th Century in the United States lighter skinned people avoided the sun Tanned skin was considered lower class But by the 1920s a cultural transformation in favor of sun tanning took place The Times 25 August 1900 1 An advertisement for a German Bath In Scotland offers For Health and Pleasure Pure Air and Sun Baths a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help All Nobel Laureates in Physiology or Medicine Nobel Media Archived from the original on 12 May 2015 Retrieved 29 April 2015 The Times 12 March 1910 12 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help The Times 4 September 1913 6 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Describing a visit by the Prince of Wales to the pretty town of Sigmaringen the reporter says The Castle possesses many delightful terraces which could be adapted for sunbathing Hanson Peter G 22 June 2009 About Face The Effects of Aging Health and Stress on Your Face FaceMaster Archived from the original on 23 April 2012 a href Template Cite web html title Template Cite web cite web a CS1 maint unfit URL link Sun and Clouds The Sun in History Magic Bullets Chemistry vs Cancer The Chemical Heritage Foundation 2001 Archived from the original on 20 June 2010 By the 1920s the therapeutic effect of the sun was widely promoted and two well publicized French personalities gave tanning a fashion boost Coco Chanel of designer fame returned to Paris after a cruise on the Duke of Westminster s yacht with a tan that became all the rage And the natural caramel skin color of singer Josephine Baker made women all over the world try to emulate her skin tone a href Template Cite web html title Template Cite web cite web a CS1 maint unfit URL link Koskoff Sharon 28 May 2007 Art Deco of the Palm Beaches Arcadia Publishing p 2 ISBN 978 0 7385 4415 1 Retrieved 11 September 2009 In 1920s France the caramel skinned entertainer Josephine Baker became a Parisian idol Concurrently fashion designer Coco Chanel was bronzed while cruising on a yacht A winter tan became a symbol of the leisure class and showed you could afford to travel to exotic climates Steele Valerie ed 2010 The Berg Companion to Fashion Berg p 554 ISBN 978 1847885630 Sunscreen Lotion Spray amp Sun Care Products Coppertone Coppertone www coppertone com Archived from the original on 26 October 2016 Retrieved 1 May 2018 Campo Riku 31 August 2010 Best in Beauty An Ultimate Guide to Makeup and Skincare Techniques Tools and Products Simon and Schuster p 185 ISBN 978 1 4391 5585 1 Heckman Carolyn J Manne Sharon L 15 September 2011 Shedding Light on Indoor Tanning Springer Science amp Business Media p 20 ISBN 978 94 007 2048 0 Jablonski Nina G 27 September 2012 Living Color The Biological and Social Meaning of Skin Color University of California Press p 185 ISBN 978 0 520 25153 3 Wright Dan 16 August 2007 Working The Tan The Daily News Record Harrisonburg Virginia Archived from the original on 20 April 2010 Retrieved 11 September 2009 The tanning industry has grown about 25 percent over the past six years according to the Indoor Tanning Association In the United States about 25 000 free standing tanning salons employ 160 000 people and generate more than 5 billion in annual revenue the association said Clark Patrick 5 October 2016 Twilight of the Tanning Salons Bloomberg News Archived from the original on 10 October 2016 Retrieved 9 October 2016 Levin Dan 3 August 2012 Beach Essentials in China Flip Flops a Towel and a Ski Mask The New York Times Archived from the original on 5 August 2012 Retrieved 5 August 2012 Taylor Angela 17 October 1969 Tan Through Fabric Lets Sun Shine In The New York Times p 55 Archived from the original on 12 October 2013 Retrieved 30 November 2014 Scorecard No nudes is good news Sports Illustrated 1 September 1969 Archived from the original on 12 October 2013 permits 40 of the sun s ultraviolet rays a href Template Cite news html title Template Cite news cite news a CS1 maint unfit URL link Tan tastic bikini that lets rays shine through Daily Express 30 May 2009 Archived from the original on 17 October 2014 Retrieved 17 September 2014 80 per cent of UV rays a stretchy yarn described as a chicken wire mesh material Dihydroxyacetone Archived from the original on 28 July 2010 Retrieved 6 July 2010 Sunless tanning A safe alternative to sunbathing Archived from the original on 16 February 2010 Retrieved 6 July 2010 External links edit nbsp Wikimedia Commons has media related to Sunbathing Aim at Melanoma Information on tanning from The Skin Cancer Foundation Archived 7 December 2011 at the Wayback Machine Research on the benefits of UV exposure Melanoma Research Alliance Retrieved from https en wikipedia org w index php title Sun tanning amp oldid 1195099234, wikipedia, wiki, book, books, library,

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