Sun reflector for face tanning skin#

Ultraviolet B (UVB) radiation is in the wavelength range 280 to 320 nm. UVA (see above) induces a cosmetic tan but little extra melanin protection against sun damage, sun burn, or cancer. However, it operates not by inducing direct DNA damage, but by producing reactive oxygen species which damage DNA indirectly. UVA is known both to cause DNA damage and to be carcinogenic. UVA is blocked less than UVB by many sunscreens, but is blocked to some degree by clothing. UVA causes the release of existing melanin from the melanocytes to combine with oxygen (oxidize) to create the actual tan color in the skin. Most UVA is not blocked by the atmosphere's ozone layer. It is present more uniformly throughout the day, and throughout the year, than UVB.

Ultraviolet A (UVA) radiation is in the wavelength range 320 to 400 nm. The ultraviolet frequencies responsible for tanning are often divided into the UVA and UVB ranges. 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).

Sun reflector for face tanning skin#

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. 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. Melanogenesis leads to delayed tanning, and typically becomes visible two or three days after exposure. In the second process, triggered primarily by UVB, there is an increase in production of melanin (melanogenesis), which is the body's reaction to direct DNA photodamage (formation of pyrimidine dimers) from UV radiation. Skin darkening from UVA exposure does not lead to significantly increased production of melanin or protection against sunburn. UVA may also cause melanin to be redistributed (released from melanocytes where it is already stored), but its total quantity is unchanged. 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. Cross-sectional view showing skin tone becoming darker due to the production of more melanin to overcome DNA damage caused by UV radiation The intensity is commonly measured by the UV Index. 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. With the production of the melanin, the skin color darkens. 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. Melanin protects the body by absorbing ultraviolet radiation. Melanocytes produce two types of melanin: pheomelanin (red) and eumelanin (very dark brown). Melanin is a natural pigment produced by cells called melanocytes in a process called melanogenesis. 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).Įxcessive exposure may in the long-term increase the risk of skin cancer, as well as depressed immune system function and accelerated aging of the skin. The term 'tanning' has a cultural origin, arising from the color tan. This may be the result of different skin types and natural skin color, and these may be a result of genetics.

Some people tan or sunburn more easily than others. Moderate exposure to direct sunlight contributes to the production of melanin and vitamin D by the body.Įxcessive exposure to ultraviolet rays has negative health effects, including sunburn. Impact on skin health Moderate exposure A sun tanned arm showing browner skin where it has been exposed Some people use chemical products which can produce a tanning effect without exposure to ultraviolet radiation, known as sunless tanning. People who deliberately tan their skin by exposure to the sun engage in a passive recreational activity of sun bathing. 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. Sun tanning or tanning is the process whereby skin color is darkened or tanned. For the 2013 album by Deafheaven, see Sunbather (album).Ī visible tan line on a woman whose skin has been darkened by ultraviolet exposure, except where covered