But your heredity dictates how much melanin your body's melanocytes naturally will produce. For example, the skin of African-Americans contains enough melanin to create a black or brown skin color, while the skin of Caucasians has less melanin and is pale. In order to most effectively avoid overexposure, a tan should be acquired gradually, according to the guidelines prescribed by your salon professional.
A sunburn, or erytherma, occurs when too much ultraviolet light reaches the skin and disrupts the tiny blood vessels near the skin's surface. Cells in the epidermis' germinative layer also called the living epidermis are constantly reproducing and pushing older cells upward toward the horny layer dead epidermis , where they are sloughed off in about one month.
As your skin replaces its cells, the cells laden with melanin are removed. So, the tanning process must continue with the new cells. Ultraviolet light, whether produced by the sun or an indoor tanning unit, consists of two main components, UVA and UVB, both of which contribute differently to your tan. Hydrate, eat great : Drink lots of water and choose whole, unprocessed foods. Your skin will thank you!
UV Radiation. Skin Type. Atypical Moles. This Is Skin Cancer. Ask the Expert. Healthy Lifestyle. Skin Cancer Information. Child Sun Safety. Make a Donation. If you're thinking about using a sunless tanner, it's a good idea to avoid airbrush or spray-on tans.
Spray tans may have unknown health risks because people can breathe in the spray, or the tanner may end up on their lips or eye area. Reviewed by: Patrice Hyde, MD. Larger text size Large text size Regular text size.
Here are some tips to enjoy the great outdoors while protecting your skin and eyes from sun damage: Wear sunscreen with an SPF of at least 30 every day, even on cloudy days and when you don't plan on spending much time outdoors. If you don't want to wear a pure sunscreen, try a moisturizer with sunscreen in it, but make sure you put on enough. Ideally, it should also be hypoallergenic and noncomedogenic so it doesn't cause a rash or clog your pores. Even if you don't get a sunburn, UVA rays could still be doing unseen damage to your skin.
Reapply sunscreen after swimming or sweating. Take frequent breaks. The sun's rays are strongest between A. During those hours, take breaks to cool off indoors or in the shade for a while before heading out again. Other things to know when it comes to avoiding sun damage: You probably know that water is a major reflector of UV radiation — but so are sand, concrete, and even snow. Snow skiing and other winter activities carry significant risk of sunburn, so always apply sunblock before hitting the slopes.
Certain medications, such as antibiotics used to treat acne and birth control pills, can increase your sun sensitivity as well as your sensitivity to tanning beds. Ask your doctor whether your medications might have this effect and what you should do. If you are Caucasian and you don't have a tan, then the cells in your skin are not protected from the sun 's ultraviolet radiation.
You are therefore an easy target for sunburn if you spend too much time in the sun. As anyone who has a sunburn knows, sunburn leaves your skin red and extremely painful. In severe cases the skin forms blisters. When you get sunburn, your skin is actually damaged by UV radiation and your body is responding to the damage. Here is a specific medical description of what is happening from this article :. Sunburn is a popular term applied to the marked erythema and pain that commonly follows injudicious sun exposure.
A sunburn is really a delayed ultraviolet B-induced erythema caused by an increase in blood flow to the affected skin that begins about 4 hours and peaks between hours following exposure [23, 30, 31]. The underlying cause of this vascular reaction is direct and indirect damage to specific cellular targets from photochemical reactions and the generation of reactive oxygen species [32]. Damage to DNA, and the activation of several inflammatory pathways, particularly involving prostaglandins [27, ], are thought to trigger this reaction, ultimately leading to vasodilation and edema.
Biologic response modifiers released by both keratinocytes and lymphocytes also play a role []. The development of erythema therefore implies that enough ultraviolet damage has occurred that inflammatory pathways have been activated. Erythema is probably best thought of as a total failure of sun protection, and is a marker for severe UV damage. Several lines of evidence suggest a relationship between erythema and DNA damage. There is rough correlation between pyrimidine dimer yield and susceptibility to erythema with sun exposure [56].
Wavelengths that are the most efficient at producing erythema are also the most efficient at producing pyrimidine dimers [56]. From a scientific point of view, a sunburn can be viewed as a marker for a substantial ultraviolet over-exposure that has clinical implications for skin cancer risk. It is now appreciated that there is a linkage between a history of repeated, severe sunburn and increased risk for melanoma [1, ] and non-melanoma skin cancer [].
Translating, what this quote says is that when you get a sunburn, what you are really getting is cellular damage from ultraviolet radiation. The body responds to the damage with increased bloodflow to the capillary bed of the dermis in order to bring in cells to repair the damage.
The extra blood in the capillaries causes the redness -- if you press on sunburned skin it will turn white and then return to red as the capillaries refill. Cod liver oil supplies Vitamin D, and it was commonly prescribed before the advent of Vitamin D fortified milk. The other way to get Vitamin D is to expose your skin to ultraviolet light. Ultraviolet light converts 7-dehydrocholesterol flowing in your bloodstream into Vitamin D. See How Vitamin D Works for details.
Sunscreens block or absorb ultraviolet light. You can block UV light with opaque creams like the white zinc oxide cream that you see lifeguards putting on their noses.
You can also absorb UV radiation in much the same way that melanin does. The first and most common of the absorption chemicals is PABA para-aminobenzoic acid. It absorbs UVB. If you have sensitive skin, take care when using sunscreen with PABA as it may cause irritation or an allergic reaction in some individuals.
Other sunscreen chemicals include:. The SPF acts like a multiplying factor. In order for the sunscreen to work, however, you have to apply plenty and it has to stay on. You should apply it about half an hour before going out in the sun or the water so it can bind to your skin -- if you don't, then it is very easy for the sunscreen to wash off. Dermatologists are calling it the best sunscreen in the world.
There is something about this whole discussion that is fascinating. On your body is an organ -- the skin -- and it responds in all of these interesting ways to sunlight. For more information on sunburns, sun tans, sunscreens and related topics, check out the links on the following page. Sign up for our Newsletter! Mobile Newsletter banner close.
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