Freckle: Difference between revisions
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Upon exposure to the sun, freckles will reappear if they have been altered with [[Cream (pharmaceutical)|creams]] or [[laser]]s and not protected from the sun, but do however fade with age in some cases. |
Upon exposure to the sun, freckles will reappear if they have been altered with [[Cream (pharmaceutical)|creams]] or [[laser]]s and not protected from the sun, but do however fade with age in some cases. |
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Freckles are not a skin disorder. People with freckles usually have a lower concentration of photoprotective melanin and are therfore more susceptible to the harmfull effects of UV-radiation. An overexposure of UV-radiation should be avoided. However due to the debate about the safety of [[sunscreen]], protective clothing should be the preferred method. <ref name="Hanson">{{cite journal |author=Hanson Kerry M.; Gratton Enrico; Bardeen Christopher J. |title=Sunscreen enhancement of UV-induced reactive oxygen species in the skin |url=http://dx.doi.org/10.1016/j.freeradbiomed.2006.06.011|| journal=Free Radical Biology and Medicine |volume=41 |issue=8 |pages=1205-1212 |year=2006 }}</ref> |
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Freckles are not a skin disorder. People with a predisposition to freckles may be especially susceptible to sunburn and [[skin cancer]], and should therefore take extra care to protect themselves in the sun. |
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<ref name=Garland> {{cite journal |author=Garland C, Garland F, Gorham E |title=Could sunscreens increase melanoma risk? |url= http://www.ajph.org/cgi/reprint/82/4/614 |journal=Am J Public Health |volume=82 |issue=4 |pages=614-5 |year=1992 |pmid=1546792 |issn=}}</ref> |
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[http://www.yourhealthbase.com/sunscreens.htm Sunscreens and Cancer by Hans R Larsen] |
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Revision as of 09:30, 11 March 2008
Freckles are small colored spots of melanin on the exposed skin or membrane of people with complexions fair enough for them to be visible.
Having freckles is genetic and is related to the presence of the melanocortin-1 receptor MC1R gene variant, which is dominant. Freckling can also be triggered by long exposure to sunlight, such as suntanning. When the sun’s rays penetrate the skin, they activate melanocytes which can cause freckles to become darker and more numerous, although the distribution of melanin is not the same. Fair hair such as blonde, or more commonly red hair, are usually common with the genetic factor of freckles, but none so much as fair or pale skin.
Freckles are predominantly found on the face, although they may appear on any skin exposed to the sun. Freckles are rare on infants, and more common on children before puberty; they are less common on adults.
Freckles are clusters in which the produced melanin is more concentrated.
Upon exposure to the sun, freckles will reappear if they have been altered with creams or lasers and not protected from the sun, but do however fade with age in some cases. Freckles are not a skin disorder. People with freckles usually have a lower concentration of photoprotective melanin and are therfore more susceptible to the harmfull effects of UV-radiation. An overexposure of UV-radiation should be avoided. However due to the debate about the safety of sunscreen, protective clothing should be the preferred method. [1] [2] Sunscreens and Cancer by Hans R Larsen
Two types of freckles
Ephelides is a genetic trait. It’s used to describe a freckle that is flat, light brown or red, and fades in the winter. Ephelides are more common in those with light complexions and with the regular use of sunblock, can be suppressed.
Liver spots (also known as sun spots) are freckles that do not fade in the winter. Rather, they form after years of exposure to the sun. Lentigines are more common in older people.
References
- ^ Hanson Kerry M.; Gratton Enrico; Bardeen Christopher J. (2006). "Sunscreen enhancement of UV-induced reactive oxygen species in the skin". Free Radical Biology and Medicine. 41 (8): 1205–1212.
{{cite journal}}: Cite has empty unknown parameter:|1=(help)CS1 maint: multiple names: authors list (link) - ^ Garland C, Garland F, Gorham E (1992). "Could sunscreens increase melanoma risk?". Am J Public Health. 82 (4): 614–5. PMID 1546792.
{{cite journal}}: CS1 maint: multiple names: authors list (link)
See also
