The explanation: The same type of ultraviolet radiation — UVB rays — that sets your skin on fire is also behind your bronzing. More specifically, UVB rays are responsible for a type of tanning called delayed pigment darkening. That means the healing of your sunburn may happen to coincide with the deepening of your tan. What exactly is a tan, then, if not a faded-out sunburn?
Related: Herpes From a Tanning Bed? Here are three tips to apply sunscreen the right way. Have a personal health story to share?
We want to hear it. Tell us at YHTrueStories yahoo. Amazon shoppers are living in these on-sale joggers: 'OMG these are the most comfortable pants I've ever owned! Dust like nobody's watching. Wear a hat and sunglasses to protect your scalp and eyes, and where possible, cover up your skin to avoid excessive exposure to the sun.
When you cannot or do not want to avoid the sun for long periods of time, it is essential to wear sunscreen. Sunscreen contains a chemical that absorbs UV radiation rather than the radiation being absorbed by your skin, so the chance of the UV damaging your DNA, and therefore of getting skin cancer, is greatly reduced. On the contrary, high SPFs do exactly the same job as low SPFs, but they last longer, so you can stay out in the sun for longer without reapplying the lotion although it is still advisable to reapply regularly as the lotion can rub or sweat off of your skin.
Contrary to popular belief, sunscreens do not prevent tanning, and in fact, they can enable you to stay browner for longer because you will avoid burning, and the damaged skin will not peel away. I don't go outside very much, as my schedule doesn't allow it most of the time.
Any advice on what to do? The factor is the amount by which the amount of UV rays that hit your skin is reduced. So wearing SPF 30 sunscreen means 30 times fewer UV rays hit your skin than would be the case if you had no protection. This new underlying skin that is revealed, will it be tanned? If so, this would explain people's observation and mine that red, sunburnt skin, eventually "turns" brown after a few days.
Should we avoid fresh air because oxygen is a component in the production of damaging free-radicals? Is it possible that other things in our diet or environment are interacting with excessive sun exposure to produce increased skin tumors?
Time to re-examine this topic more objectively. Thank you, Randy Green, for your great comment that lists many of the arguments for moderate, sensible, gradual … sun exposure.
Holick, Vieth, Garland et al. Of course, much depends on the skin type: if you are type 1 stay out of the sun and cover up. Beyond skin type 3 the precautions and rules barely apply even though a dark-skinned person may get skin cancer once in a blue moon. Skin cancer is rampant among the white immigrant population of Australia, but certainly not among Aborigines.
There seems to be a certain rather narrow racially prejudiced? Tanned skin is desirable in many but certainly not all cultures. Where I live, in Hawaii, it is a natural result of our environment unless you hide from the sun and heed Dr.
I like to blend in with the rest of the totally mixed Hawaiian population that shows all healthy skin pigmentation shades from white to black. Sunburns will give you skin cancer guaranteed, and the dead from it is fast and very painful.
So go and catch some sun you idiots. You will look good in your casket. To tan or not to tan that is the question. The author obviously thinks not. Not all end up with a leather hide maybe the people that overdo it.
Ten years ago, I developed agonising muscle pain and myriad other symptoms. So, I did my own research, started myself and my husband on 10 k D3 daily for six weeks, at which point we got our levels checked. It was the month of June. They were just about within normal levels, so we used a maintenance dose from thereon in. What we noticed then, and every year since, is that, if we maintain our levels, and start exposing skin from the earliest possible sunshine, we never burn my husband has fair skin, freckles and used to have ginger hair!
It seems that, if one has enough D3, it acts as a protection against burning. I also discovered this fifty years ago when I lived in Spain for a year as an 18 year old, and built up a tan gradually from the earliest sunny weather.
I never burnt at the height of summer. One of the neat things about skin that makes it different from a lot of other organs is the fact that it does have to deal with the real world. Therefore it is loaded with sensors, and it also has a very tough layered design so that it can handle realities of the environment like abrasion and sunlight.
If you take a look at a cross section of typical skin like the skin on your arm or leg you find that it is made up of two main layers: the epidermis on the outside and the dermis on the inside. The epidermis is the barrier, while the dermis is the layer containing all the "equipment" -- things like nerve endings, sweat glands, hair follicles and so on.
To the right is a picture to help you see what is going on. In the subcutaneous layer you may have heard of subcutaneous fat -- this is where it lives you can see the blood vessels shown as two thin red and blue lines. These vessels branch infinitely not shown into the dermis to supply the sweat glands, hair follicles, sebaceous glands and erector muscles with blood. They also fan out into the dermis's capillary bed. It turns out that the dermis is loaded with capillaries.
Capillaries satisfy the nutritional needs of the cells in the dermis, and they also help the skin perform an important cooling function in humans. The epidermis has no direct blood supply, but instead is supported and fed by the dermis.
Learn more about the dermis on the next page and how it relates to melanoma and sun exposure. The dermis is where the action is functionally. The dermis contains sweat glands, hair follicles each with its own tiny little muscle so that your "hair can stand on end"! There are several different types of nerve endings:. All these different nerve endings let you sense the world. They also help you protect yourself from burns, punctures and the like by warning you when something is damaging your skin.
The epidermis is your interface to the world, and it is actually quite interesting. It has two main layers, the inner of which is living and the outer of which is dead. The dead skin cells of the outer layer are what we can actually see, and they are constantly flaking off and being replaced by new cells being pushed outward.
The living, inner layer of the skin is called the malpighian layer. The malpighian layer creates the dead cells that we can see. It is in direct contact with the dermis, which feeds and supports it. The malpighian layer is our focus of attention actually, because it is here that the sun affects the skin during tanning.
The malpighian layer is itself layered like this:. Above the granular layer is the stratum corneum. The stratum corneum is the outer layer of dead cells -- the cells that we see as our skin. The cells in this layer are filled with a protein called keratin. Keratin is a very interesting protein because it is tough -- horns, hair, hoofs, fingernails and feathers all gain their strength from keratin.
The same stuff that your fingernails are made of actually forms your visible skin but in a much thinner and more flexible layer. That is what makes your skin so tough. In parts of the body that get a lot of wear, like the palms and the feet, the stratum corneum is thicker to handle the abrasion.
Living among the basal cells in the malpighian layer is another type of cell called a melanocyte. Melanocytes produce melanin , which is a pigment that is the source of tanning.
The melanocytes are actually where a tan comes from. Here is what the Encyclopedia Britannica has to say about melanocytes:. Not only do melanocytes produce a tan, they are also responsible for the form of cancer called melanoma. Melanoma is caused by UV radiation damage to melanocytes. Repeated exposure to UV can cause cancerous mutations.
The living, inner layer is called the malpighian layer. One of the interesting things about UV radiation is that it is reflected by different surfaces. These reflections can amplify the effects of UV exposure. That is why you can get snow blindness and severe sunburns from skiing on a sunny day.
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