After a long, bleak winter, most people can't wait to go outside for the first warm spring day to soak up the sun. And the sun, in addition to other benefits, like making life on Earth possible, can be good for our health. In moderate doses, sun exposure is a good source of vitamin D. However, it's also possible to get too much of a good thing.
The sun's rays are surprisingly powerful, and some of its most powerful rays -- called ultraviolet (UV) rays -- are actually invisible. It is these rays, and not the immediately perceptible warming rays, that are dangerous. Earth's ozone layer protects us from most of these harmful rays, but not all. When they hit us, UV rays penetrate dead skin cells (which make up our outer layer of skin) and damage living cells underneath. This can cause sunburn, which, if very severe, is called sun poisoning (the scientific name for both is photodermatitis).
UV rays can damage DNA and kill skin cells. It takes a few hours for your body to respond to the burn, which is why if you get a sunburn in the afternoon, you may not realize it till the evening. Your immune system reacts to this attack on your skin by expanding the blood vessels and sending blood to the burned areas (warming and reddening your skin). This allows white blood cells to enter and repair the damaged cells.
Your body also produces melanin, a pigment that is responsible for darkening the skin (tanning) and soaking up some radiation. Melanin production increases upon a few subsequent days of sun exposure, which is why it takes a few days to get a tan. A tan protects you from sunburn, but you can easily get a sunburn or sun poisoning before your body has time to develop a tan. Of course, this reaction can be dependent on your particular skin type, which we'll discuss more later.
We'll take the next few pages to discuss the symptoms, treatment and dangers of sun poisoning. And, most importantly, we'll talk about good prevention methods. Up first, though, how can you tell the difference between sunburn and sun poisoning?
Sun Poisoning Symptoms
As we covered in the previous section, the reaction to a sunburn can depend on skin type. Most people produce two types of melanin, but in different amounts depending on their skin type. Dark-skinned people produce more eumelanin, which turns their skin brown, giving them more of a natural protection from sunburn and sun poisoning. On the other hand, people with fair skin (especially those with red hair) produce more pheomelanin. Pheomelanin doesn't brown, but rather reddens the skin, making these people all the more susceptible to sunburn and sun poisoning. So, redheads should be particularly cautious about sun exposure.
If you've just spent a day in the sun and feel a sunburn coming on, it's helpful to be familiar with the symptoms of sun poisoning. The symptoms start out appearing similar, because sun poisoning is simply a very severe sunburn. The important difference is that you might need to go to the hospital if sun poisoning symptoms start to occur.
First, let's go over some of the common symptoms of a sunburn. The damage can begin within 15 minutes of sun exposure (even though you won't feel it yet). After four to six hours, the affected skin will get noticeably red and warm (a result of the reaction of your body sending blood to the area, as we discussed on the last page). Sunburns often entail painful burning sensations, the severity of which depends on how bad the burn is. The affected skin will also begin to peel off eventually.
So the redness, burning and peeling are all normal -- albeit painful. It's time to get worried only when you experience any of the following:
- Dizziness or fainting
- Rapid pulse
- Rapid breathing
- Loss of consciousness
These are symptoms of sun poisoning -- not of a mere sunburn. Any of these, or simply abnormally severe pain, should at least prompt a call to your doctor. The last three -- dehydration, shock and loss of consciousness -- will require a trip to the hospital.
Next, we'll go over treatments.
Sun Poisoning Treatment
If you are sunburned, you will be anxious to relieve the intense burning as soon as possible. An easy homemade remedy for mild burns includes cold compresses that use a mix of equal parts milk and water. Another common home-treatment is to apply a cream or an aloe lotion, a few varieties of which should be available at any drugstore.
Don't use a lotion with a topical anesthetic, however, as these can cause an allergic reaction on sensitive skin. Also, do not use an ointment that might prevent air from getting to the skin, which will only delay natural healing.
A plain cool bath could also relieve the burning. It's best to not include soap or salts, etc. Your skin is very sensitive after a burn and these substances will likely sting. And be sure to draw the bath with cool water -- not cold. Likewise, it's good to drink cool -- not cold -- water. You'll need to stay hydrated, but cold water can promote chills. After a bath, be gentle when drying the affected skin: Use soft towels and pat dry.
Another option is silver sulfadiazine, which is a topical cream that treats and prevents infection for burned skin. Taking a painkiller or anti-inflammatory drug can help, too. Painkillers include things like acetaminophen (Tylenol), and a common anti-inflammatory is ibuprofen (Advil). Taking these early will help in particular. If you do see a doctor, he or she may prescribe stronger painkiller medication instead.
And, if you go to the hospital for dehydration, they will likely give you IV fluids. Going to the hospital might be a matter of life and death. It isn't common, but sun poisoning has been known to lead to death. Repeated sunburns or sun poisoning can also cause death later in life due to skin cancer. Read on to the next page to learn more about these dangers as well as the best ways to prevent sun poisoning.
Dangers of Sun Poisoning
Obviously, sun poisoning is no fun. You'll likely be in severe pain for a few days after the sun exposure. You may begin to lose skin 4-7 days later as well [source: WebMD]. But these are only the short-term dangers.
As we already mentioned, sun poisoning can occasionally be fatal. The sun's harmful UV radiation can also cause eye damage, even though it may not be as noticeable as a stinging sunburn. UV exposure to the eyes can increase someone's chances of developing cataracts.
We mentioned on the first page that UV light can damage DNA. This may cause the DNA to mutate, which could lead to skin cancer [source: Sobell]. Melanoma is a very serious and deadly kind of skin cancer that has been linked to repeated UV damage earlier in life.
But UV exposure can also cause other forms of skin cancer, such as basal cell carcinomas and squamous cell carcinomas, both of which are curable if caught early. Lesions caused by sun damage, called actinic keratoses, can eventually lead to squamous cell carcinomas. Luckily dermatologists can treat them in several ways, including laser treatments or freezing them through cryotherapy.
Your chances of developing skin cancer increase after repeated UV exposure, but it could only take one bad sunburn to cause cancer [source: Kidd]. Knowing this, you shouldn't let yourself go one more day in the sun without taking some important precautions.
Doctors recommend avoiding extended periods of sun exposure. But if you must be outside, the most important thing to do is use sunscreen. Apply sunscreen before you go out -- don't wait until you're already outside. And one of the most common mistakes is to forget to reapply periodically. It's also smart to make a fashion statement and wear a brimmed hat that completely shades your face.
So remember that when you're soaking up the sun, you're also soaking up dangerous UV rays. And even though you may not feel it at the moment, it could cause severe pain in the short term and, what's worse, a deadly disease in the long term.
Related HowStuffWorks Articles
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- Top 5 Tanning Myths
- Fact or Fiction: Sunburn
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