Another way the sun can kill you is through skin cancer. The sun emits light in many different wavelengths. The one that humans need to worry about are ultraviolet (UV) light waves. We can't see this wavelength with our eyes, mainly because they're shorter waves than visible light. If you've ever bought a nice pair of sunglasses, they probably claim to block out 100 percent of UV rays. This doesn't mean you can look at the sun, but it does protect your eyes while you're outside in the daytime.
These UV rays are also the way you can get skin cancer. While you might like the way you look with a tan, it's actually a sign of skin damage from UV rays. In fact, most all of the changes to your skin are from UV exposure, including wrinkles and freckles. There are springy, fibrous proteins in the skin called elastin that help keep the skin flexible and tight. Over the years, damage to the elastin from UV exposure causes it to break down. This can lead to pre-cancerous or cancerous skin lesions or tumors.
Like all cancers, skin cancer is a result of the growth of abnormal cells -- in this case, skin cells. It's the most common kind of cancer and there are three main types:
- Basal cell carcinoma
- Squamous cell carcinoma
The first two kinds aren't very serious and make up about 95 percent of all cases of skin cancer. Melanoma is very serious and accounts for 75 percent of skin cancer deaths [source: WebMD]. Doctors will tell you that exposure to the sun's UV rays is the number one cause of skin cancer, making it one of the more preventable forms of cancer. It should also be noted that UV rays from tanning beds are just as dangerous.
You can help to prevent skin cancer by staying out of the sun between the peak hours of 10 a.m. and 3 p.m., or taking extra precautions if you can't avoid prolonged UV exposure. Sunscreen with a sun protection factor (SPF) of at least 15 is mandatory to help shield you from the harmful UV rays. If you're a parent, take care of your children's needs -- 80 percent of your lifetime's UV exposure comes before the age of 18 [source: WebMD].