Ultraviolet (UV) radiation is a form of light that is invisible to the human eye, but can have serious consequences for our health. Overexposure to UV radiation can cause skin cancer, eye damage, and weaken the body's immune system. It is essential to understand the risks associated with UV radiation and take sensible precautions to protect yourself from its harmful effects. The depletion of the ozone layer has reduced the natural protection of our atmosphere against UV radiation from the sun.
Every year, more new cases of skin cancer are diagnosed in the United States than breast, prostate, lung and colon cancer combined. One in five Americans will develop skin cancer at some point in their lives, and an American dies of skin cancer every hour. Unprotected exposure to UV radiation is the most preventable risk factor for skin cancer. Other UV-related skin disorders include actinic keratosis and premature skin aging. Actinic keratoses are skin tumors that occur in areas of the body exposed to the sun.
The face, hands, forearms and the “V” of the neck are especially susceptible to this type of injury. Although premalignant, actinic keratosis is a risk factor for squamous cell carcinoma. Look for raised, reddish, rough-textured bumps and seek immediate medical attention if you discover them. Chronic sun exposure also causes premature aging, which over time can cause skin to become thick, wrinkled and leathery. Up to 90 percent of visible skin changes that are commonly attributed to aging are caused by the sun. With adequate protection against UV radiation, most premature skin aging can be prevented. Exposure to UV rays also increases the risk of potentially blinding eye diseases if eye protection is not used.
Cataracts are a form of eye injury in which the loss of transparency in the lens of the eye clouds vision. If left untreated, cataracts can cause blindness. Research has shown that UV radiation increases the likelihood of certain cataracts. Other types of eye damage include pterygium (tissue growth that can block vision), skin cancer around the eyes, and degeneration of the macula (the part of the retina where visual perception is most acute). All of these problems can be reduced with appropriate eye protection. Look for sunglasses, eyeglasses, or contact lenses if you wear them, that offer 99 to 100 percent UV protection.
Scientists have discovered that overexposure to UV radiation can inhibit the proper functioning of the body's immune system and the skin's natural defenses. For example, the skin normally acts as a defense against foreign invaders, such as cancers and infections. However, excessive exposure to UV radiation can weaken the immune system and reduce the skin's ability to protect itself against these invaders. UVA rays, with a relatively long wavelength, account for approximately 95 percent of the UV radiation that reaches the Earth's surface. It can penetrate the deeper layers of the skin and is responsible for the immediate tanning effect. In addition, it also contributes to skin aging and the formation of wrinkles. Recent studies clearly suggest that UVA rays may also increase the development of skin cancers.
Excessive exposure to UV radiation has a detrimental suppressive effect on the immune system. Sunburn can change the distribution and function of disease-fighting white blood cells in humans up to 24 hours after sun exposure. Repeated overexposure to UV radiation can cause even more damage to the body's immune system. To see how well your immune system works, look at how quickly something deteriorates when it dies and your immune system stops working. Understanding these risks and taking sensible precautions will help you enjoy the sun while reducing your chances of developing sun-related health problems. Look for sunglasses or eyeglasses that offer 99-100% UV protection and seek immediate medical attention if you discover any suspicious bumps or lesions on your skin.
