The skin is the body’s largest organ. It protects against heat, sunlight, injury and infection. Although the skin is our 1st line of defense, some if us don’t consider the necessity of protecting our skin. The need to protect our skin has become very clear over the years, supported by several studies linking overexposure to sun with skin cancer.
The sun emits radiation in the form of ultraviolet (UV) light, which is classified into 3 types by wavelength (UVA, UVB, UVC). In the stratosphere there is a protective layer known as the ozone layer which block all UVC light (the shortest wavelength) but UVA and UVB light can pass through the atmosphere. Because UVB and UVA light can reach the Earth’s surface, it is important to protect yourself when you will be exposed to sunlight.
UV radiation is at its highest when and where the sun’s rays are strongest. This means the levels are the highest around noon on a clear sunny day as well as during the summer months. Sun damage can also occur on a cloudy day as well as in the winter. One should also be cautious near reflective surfaces like water, snow and sand. These and even the windows of a building can reflect (reflection intensifies the light) the damaging rays of the sun, increasing the chance of sunburn even if you’re in what you consider a shady spot.
(This next tip was new to me.) Extra caution should be taken when you are at higher altitudes. You can experience more UV exposure at higher altitudes because there is less atmosphere to absorb the UV radiation.
UVA vs UVB
Both reach the Earth’s surface because they are not fully absorbed by the ozone layer. UVA penetrates deeply into the skin and causes wrinkling and leathering of the skin (the effects associated with “photoaging”). The UVB types causes burns. Sunburns significantly increases ones’s lifetime risk of developing skin cancer. It is also especially important that kids be kept from burns as well. Both UVA and UVB can cause skin cancer. Indoor tanning sunlamps also produce harmful UV rays that just like the sun’s rays, can cause other complications besides skin cancer (eye problems, a weakened immune system, age spots, wrinkles and leathery skin). More people develop skin cancer because of indoor tanning than developing lung cancer from smoking.
AFFECTS OF UV RADIATION
Affects of UV radiation ranges from the short term affect of sunburn to the long term affect of skin cancer. Every year in the U.S., over 1 million people are diagnosed with skin cancer and as a result of skin cancer 1 person dies every hour (every 57 minutes). According to the CDC, skin cancer is the most common form of cancer in the U.S. Each year nearly 5 million people are treated for skin caner in the U.S. Basal cell carcinoma is the most common and Squamous cell carcinoma is the 2nd most common skin cancer. 1 in 5 Americans will develop skin cancer in the course of their lifetime. Each year in the United States there are more cases of skin cancer than the combined incidence of cancer of the breasts, prostate, lung and colon. About 90% of non melanoma skin cancers are associated with exposure to UV radiation from the sun.
WHO IS AT RISK?
UV radiation can adversely affect everyone. Some people are just at a higher risk for skin cancer when overexposed to UV radiation. People who spend an excessive amont of time in the sun and those who burn easily and frequently are at greater risk. The risk of skin cancer is not equal for all people, but everyone should take precautions. Although melanoma is uncommon in African Americans, Latinos and Asians, it is frequently more fatal for these populations. Everyone is equally at risk for eye damage due to overexposure. In case you didn’t know, plants and animals are also affected by UV radiation. Overexposure affects the rate at which a plant carries out photosynthesis. Animals, especially those with little or no hair, are susceptible to sunburn- this is why pigs (and their hippo and warthog relatives) often coat their skin with mud, which acts like sunscreen.
PROTECTING YOUR SKIN
There are a few easy things that can be done everyday to protect your skin from the harmful effects of UV radiation from the sun:
Wear proper clothing such as long sleeved shirts and pants.
Dark clothing provide more protection than light colors; if you can see through the clothing, UV light can get through it.
Tightly woven fabrics are better than loosely woven fabrics.
Dry clothing provides more protection than wet clothing.
Clothing with special coatings to help absorb UV rays is available; the label listing UV protection factor (UPF) value (the level of protection the garment provides from the sun’s UV rays; on a scale from 1 to 50+; the higher the UPF, the higher the protection).
Image Credit: Sun Chasers
Laundry detergent-like products to use in the washing machine can increase the UPF value of clothes you already own; it adds a layer of UV protection without changing the color or texture of your clothes (*this is useful but it is not exactly clear how much it adds to the protection against UV rays).
Wear a wide brimmed hat to protect your head and eyes.
Wear UV resistant sunglasses to protect your eyes; UV rays can burn the cornea and cause cataracts which could result in blindness; make sure sunglasses provide 100% UV protection (doesn’t matter how dark or expensive they are).
Go for the shade: stay out of the sun, if possible, between the peak burning hours (10am-4pm), according to the CDC and WHO.
Wear sunscreen and reapply as needed.
Do frequent skin self checks (early detection may save your life) (more information here on what to look for).
Sunscreen prolongs the amount of time it takes for the sun’s rays to cause reddening of the skin. The broad spectrum variety protects against overexposure to ultraviolet A (UVA) and ultraviolet B (UVB) rays. The FDA recommends using sunscreens that are not only broad spectrum but also have a sun protection factor (SPF) value of at least 15 for protection against sun-induced skin problems. It must be reapplied throughout the day especially after swimming and sweating, even if labeled “Water Resistant”. Sunscreen should be applied at a rate of 1 ounce every 2 hours. Depending on how much of the body needs coverage, a full day (6hours) outing could require one whole tube of sunscreen.
Let’s get into more details on SPF. There are many misconceptions and untruths when it comes to SPFs. Sun Protection Factor, best known as SPF, measures the time it would take one to sunburn if they weren’t wearing any sunscreen as opposed to the time it would take wearing sunscreen. You would think that an SPF 30 is twice as good as SPF 15 and so on, but that’s not how it works. SPF 15 blocks about 94% of UVB rays. SPF 30 blocks about 97% and SPF 45 blocks 98%. The higher SPF blocks slightly more UVB rays, but none offers 100% protection. SPF 15 will delay the onset of a sunburn in a person who would otherwise burn in 10 minutes to burn in 150 minutes (it allows a person to stay out in the sun 15x longer; SPF 30= 30x longer; SPF 45= 45x longer and so on). Currently there isn’t a uniform measure of UVA absorption. The bottom line is: the longer you plan to spend outdoors, the higher the SPF should be. Regular daily use of sunscreen with an SPF 15 or higher reduces the risk of developing squamous cell carcinoma by 40% and the risk of developing melanoma by 50%, according to the CDC.
Some of you may be familiar with or have heard the meteorologist mention UV Index. This is a forecast that lets you know if you are at risk for overexposure to the sun. Index levels range from 2 to 11+, where level 2 is low risk and levels 6 and above are high. Check the UV index before going out to protect yourself from sun- related illneses (epa.gov/sunwise.uvindex.html).
An estimated 73,870 new cases of invasive melanoma will be diagnosed in the U.S. in 2015.
An estimated 9,940 people will die in 2015.
Melanoma accounts for less than 2% of skin cancer cases, but the vast majority of skin cancer deaths.
Of the 7 most common cancers in the U.S., melanoma is the only one who’s incidence is increasing.
About 86% of melanomas can be attributed to UV radiation from the sun.
Melanoma accounts for 6% of cancer cases in teens 15-19 years old.
On average, a person’s risk for melanoma doubles if he or she has had more than 5 sunburns.
Preventing harmful and even deadly damage from the sun’s UV rays is an inexpensive and easy thing to do. There are many products available that we can use to help us. I recently saw a piece that proved that inexpensive sunscreen (Equate brand from Walmart) was just as effective, if not more effective, than a more popular national brand name. We just need to be more proactive and not only apply the most appropriate sunscreen daily, but also remember to reapply it while still being exposed.
As usual, the information in this post is for informational purposes only and you should contact your own health care professional for treatment and/ or advice.