How and why does the Skin Tan? The Theory Behind Revealed

Just how does the skin tan? Why? If lying under the hot sun makes our skin tan, how do sunless tanning sprays work? And what about tanning beds? Curious questions of curious minds - all answered here in a layman's perspective.

Natural tanning facts

Let's talk about it in words simple to understand. The 'tan' is actually a colored pigment in the skin which protects the skin from excessive UV radiation. Ultraviolet (UV) rays are part of a vast spectrum of rays emitted by the sun. More the exposure to UV rays, more is the pigment produced by the skin glands.

The outer layer of the skin, called epidermis, contains three kinds of special cells. The one that concerns us, and what we are talking about now, is the melanocytes.

Melanocytes are the cells that produce the colored pigment - melanin - which makes the skin look 'tanned'. The amount of naturally produced melanin varies from race to race as it depends wholly on heredity. African-Americans have high amounts of melanin which makes their skin look black or dark brown. Caucasians have much lesser melanin which makes their skin look light.

It is the skin's natural tendency to produce more melanin when exposed to UV rays, as melanin blocks the harmful rays. If white skinned people are exposed to UV rays, their skin looks a shade darker. Thus it's literally a 'browning' of the skin. Excessive UV rays are harmful because they cause bursting of tiny blood vessels in the skin, which leads to swelling and reddening (a sunburn as it's called).

Indoor tanning beds

The indoor tanning bed simulates the emission of UV rays. Special lamps in the equipment emit a controlled amount of UV rays according to specific needs of tanning. The skin responds by producing melanin, thus giving you a tan. Since the radiation is carefully controlled, indoor tanning is considered safer than tanning out in the sun.

UV rays, if further broken down for analysis, consist of UVA, UVB and UVC rays. UVC rays never reach us as they are blocked by the ozone layer. Of the remainder, UVA make up for 95% and UVB 5%. They each have their specific roles which you can find out if interested. The tanning beds have control over these specific rays and that makes them a better bet than the beach.

Sunless tanning products

Some of these products go straight to the melanocytes and get them to produce more melanin, or so they claim. Many products contain dihydroxyacetone which is a colorless sugar that interacts with dead cells of the epidermis and thereby changes color. This change lasts for five to seven days. Other products like tanning pills produce the pigment canthaxanthin throughout the body including the skin, which gives it the orange brown color. But mind you, some of these chemicals may be harmful. Always lay your hands on all the information you can.

Not many people may know it but some types of medications induce/increase photosensitivity in our body. By this we mean that our skin develops a tendency to show increased sensitivity when exposed to sun. While it may not harm us to a great extent, the emergence of this condition may definitely come as a blow to those who wanted to get a sun tan.

Drug-induced photosensitivity manifests itself mostly in the form of prominently visible sunburn. Important point is that not always are we aware that our boy has developed this photosensitivity. Only when it manifests itself is when we become aware of it.

The main reason for the occurrence of this condition is the intentional or unintentional application or consumption of skin-affecting products and medication. The visible signs of such a reaction emerge when the skin comes in contact with ultraviolet radiation. The severity of sunburns is another sign of our skin becoming photosensitive. At this stage, people develop rashes in areas that were exposed to the sun.

The situation might not be bothersome one if you plan to spend most of your time inside. However, care is supposed to be taken if you plan to get a sun tan. In that case, you need to either stay away from outdoor tanning or tell the tan-bed administrator about your skin's photosensitivity. A suitable solution would then be found out for you.

Even otherwise, if you are those who like the color of your skin tanned but find yourself at a stage wherein you need to take medication or topical products, then it is better to consult your pharmacist about the photosensitive reaction of these medications. He/she is the best person to tell you more about both prescription and non-prescription drugs, cosmetics, shampoos, herbal and other similar products.

Drug-induced photosensitivity can occur in anyone. However, its intensity and severity may vary from case to case. Most risk is faced by those who have a fair complexion, have light brown, red, or blonde hair, have green or blue eyes, and who do not tan because of quick sunburns. If one has a history of severe sunburn(s), then too the risk of developing photosensitivity is increased. The same may be the result if one has a history of allergies to topical agents or cosmetics.

The medications that you need to watch out for, include drug types like antihistamines, contraceptives (oral & estrogens), coal tar and derivatives, non-steroidal anti-inflammatory drugs, psoralens, phenothiazines, sulfonylureas, sulfonamides, thiazide diuretics, tetracyclines, and tricyclic antidepressants.

The list of photosensitizing substances is a pretty big one. However, it is not an exhaustive list. In order to know about what can harm you or not, it is best that you consult either your pharmacist or your physician. Even otherwise, not each one of us may respond to these medications in the same way. This means that you do not need to panic at the sight of these medications on your prescription.

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