Some of the more commonly recommended supplements are antioxidants, such as vitamin A and vitamin E. In addition to providing pigmentation for the cells, melanin also absorbs harmful UV rays and protects against cellular damage from UV light exposure.
Melanin levels are generally determined by genetics, but they can be influenced by outside sources, such as sun exposure, hormones, or even age. Learn more about how to get even skin tone. Hyperpigmentation of the skin is an aesthetic rather than a medical concern for people most of the time.
Well share 10 at-home treatments you can try…. How one dermatology appointment — and facing the statistics — helped me kick my tanning habit for good. Here are 16 of the best sunscreens on the market in spray, lotion, and solid forms, and for different needs. They're tried and true. Everyone can benefit from a good facial cleanser, and many products are specially formulated for dry, sensitive skin.
Blue lips are most often caused when something is preventing you from getting enough oxygen into your body. Read on to discover some of the causes of…. Health Conditions Discover Plan Connect. Understanding the Benefits of Melanin. Definition Benefits Everyone has it Too little More melanin Bottom line Melanin is the pigment that is responsible for our beautiful variety of skin tones and shades, eye colors, and hair colors.
What is melanin? Darker-skinned individuals also age better, as their skin is better protected from sun damage. It is the UV component of sunlight that helps the body utilize vitamin D. This vitamin helps promote bone growth, maintaining the right balance between calcium and phosphorus in the body.
A deficiency of vitamin D leads to rickets and similar diseases. It seems that, as early peoples migrated away from the equator into areas less exposed to the sun, there was not enough UV radiation to produce sufficient vitamin D to prevent diseases such as rickets.
Their bodies compensated by producing less melanin, so that more sunlight would be allowed through. They could then produce sufficient vitamin D with less exposure to sunlight. Light-skinned people visiting sunny locations may not have enough melanin to block the sun sufficiently, and may burn their skin without the protection of sunblock.
Dark-skinned people visiting areas where there is less exposure to the sun may apparently not produce enough vitamin D, but can get it from supplements or food sources. Many foods such as milk and bread are now vitamin D fortified. As the distribution map of skin color shows, skin color variation is not deter mined purely by distance from the equator.
For example, people in snow-covered areas often have a dark skin tone. This may be because they are exposed to high levels of reflected UV radiation from the snow, or because their diet with its high proportion of fish is rich in vitamin D.
The popularity of tanning seems cyclical, alternately being perceived as a healthy vibrant look and as a worrying reminder of the dangers of sunburn and carcinogenic melanomas. Light skin becomes darker upon exposure to ultraviolet radiation. Sunshine is the primary source of UV radiation, but artificial sources such as tanning beds produce similar effects.
Skin is alive, so when melanin is destroyed by UV ra diation, the skin responds to this damage. Skin cells will produce more melanin, replacing what has been lost and increasing the percentage of melanin in the skin. This melanin has two effects, acting as a barrier to protect the skin from further damage, and darkening the natural color of the skin.
Ultraviolet light produced in a tanning bed causes the same effect. Melanogenesis is the name of the process where melanins are produced by specialized pigment cells called melanocytes, in response to UV radiation.
This creates a long-lasting tan. Regular tanning beds use several fluorescent lamps see light bulbs and lamps that have phosphor blends designed to emit UV in a spectrum that is somewhat similar to the sun.
Tanning bulbs are long fluorescent tubes, and fall into two main categories: low pressure lamps and high-pressure bulbs. Each bulb typically has a power between W and W.
Alternative designs use high-powered parabolic lamps. The number of bulbs used by tanning beds vary: those designed for the home use 20 to 30 bulbs, commercial beds use 30 to 40 bulbs, and specialist stand-up booths use as many as 60 bulbs.
A tanning bed or sun bed whether at home or in a salon is a device emitting ultraviolet radiation used to produce a cosmetic tan. Overexposure to UV radiation from the sun and artificial sources is of considerable concern for its adverse effects on health.
UV radiation plays an important role in the development of skin cancer, cataracts, see colorblindness , and other eye conditions. It also suppresses the immune system. Cumulative UV radiation ages the skin prematurely. An alternative method of darkening the skin is the use of tanning lotions. These lotions use a wide range of active ingredients. One of the original sunless tanning lotions caused streaking and an orange skin tone, which gave the fake tan a bad reputation.
Lotions that contain dihydroxyacetone DHA as the active ingredient are used in many sunless tanning products. DHA, which is derived from plant sources like sugar beets and sugar cane, is a colorless sugar that interacts with the dead cells located in the stratum corneum of the epidermis. As the sugar interacts with the dead skin cells, a color change occurs. This change usually lasts about five to seven days from the initial application.
Another sunless tanning product is a tanning pill that contains canthaxanthin, most commonly used as a color additive in certain foods see plants and other organic molecules.
While the FDA has approved the use of canthaxanthin in food, it does not approve its use as a tanning agent. The differences in human skin and hair colour are among the most noticeable features of human variability. Skin and hair colour is primarily determined by the genes we inherit from our parents. But what is it that makes black skin and red hair? Skin colour or pigmentation is determined by three pigments or chromophores :.
Skin colour Heavily melanised naevus. Melanin content of skin is the main determining factor of skin and hair colour; hair is considered a form of skin with regards to pigmentation. Melanin is synthesized by melanosomes found in skin cells called melanocytes. Whether you have dark skin or light skin depends on the amount and type of melanin produced in your skin. There are two types of melanin and the relative amounts of each determine your skin and hair colouring.
The table above gives a very simplistic explanation for skin and hair colour determination. Many other factors are involved, including a gene protein called melanocortin 1 receptor MC1R. Increased activity of MC1R leads to the production of more eumelanin and less phaeomelanin, resulting in darkening of skin and hair. People who have impaired MC1R genes tend to have red hair and fair skin with freckles. This gene mutation increases the risk of skin cancer , particularly melanoma. Changes in gene activity associated with skin and hair colouring has been occurring since the evolution of mankind.
Migration and movement of humans over the continents meant skin colour evolved quickly and readily as an adaptation to new environments.
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