“As ozone depletion becomes more marked and as people around the world engage more in sun-seeking behaviour, the risk of developing health complications from over-exposure to UV [ultraviolet] radiation is becoming a substantial public health concern.”—DR. LEE JONG-WOOK, FORMER DIRECTOR GENERAL OF THE WORLD HEALTH ORGANIZATION.
MARTIN, a fair-skinned man from Northern Europe, fell asleep in the shade of a beach umbrella on the Italian coast. When he awoke, he found that the shade had moved and that his legs were no longer white but an angry red. “I had to go to the hospital emergency room,” Martin explains. “My legs were as stiff and swollen as two sausages. In the two or three days that followed, I was in terrible pain. I could neither stand nor bend my legs. The skin was so tight that I was afraid it would burst.”
Many believe that only light-skinned people like Martin need to fear exposure to sunlight. However, while darker-skinned people have greater protection against sunburn, they can still develop skin cancer. And their cancer often goes undetected until it reaches a dangerous stage. Other dangers connected with overexposure to the sun include damage to the eyes and to the immune system, problems that may not appear until years after the damage is done.
Of course, the level of UV radiation is generally higher the closer one gets to the equator. So those living in the Tropics or the subtropics and those traveling to such areas should take extra precautions. One reason for doing so is that the atmosphere’s protective ozone layer has reportedly become thinner in recent years. Let’s examine some of the potential dangers posed by overexposure to the sun.
Eye Damage
As many as 15 million people earth wide are blind because of cataracts, the world’s leading cause of blindness. Cataracts form when proteins in an eye’s lens unravel, tangle, and accumulate pigments that cloud the lens. Cataracts are one of the long-term effects of exposure to UV radiation. In fact, it is estimated that up to 20 percent of cataracts are caused or worsened by chronic sun exposure.
Sadly, the so-called cataract belt near the equator includes developing countries where the majority of people are poor. Thus, millions of poor people in Africa, Asia, Central America, and South America are blind because they cannot afford to have an operation to remove their cataracts.
Damage to the Skin
One third of all cancers diagnosed worldwide are skin cancers. Some 130,000 new cases of melanoma, the most dangerous form of skin cancer, are reported each year. And between two and three million new cases of other skin cancers, such as basal cell carcinomas and squamous cell carcinomas, occur. It is estimated that some 66,000 people die each year from skin cancer.
How does sunlight damage your skin? The most common and best-known acute effect of overexposure to the sun is sunburn, or erythema. Its immediate effects can last for days and may include blistering and peeling.
When sunburn occurs, UV radiation kills most of the cells in the outer layer of the skin and damages deeper layers. Any change in the color of a person’s skin as a result of sun exposure is a sign of damage. Cancer can result when damage occurs to the DNA of genes that control the growth and division of skin cells. Sunlight also alters the texture of the skin and weakens its elasticity. This leads to premature wrinkling and sagging, as well as easy bruising.
Immune-System Damage
Studies have shown that when the skin absorbs too much UV radiation, the activities of certain parts of a person’s immune system are adversely affected. This may reduce the body’s ability to defend itself against some diseases. Even moderate sun exposure has been known to increase the risk of bacterial, fungal, parasitic, or viral infections. Many people notice that being in the sun causes them recurrent eruptions of cold sores, or herpes simplex. A World Health Organization (WHO) report explains that one category of ultraviolet light, known as UVB, “appears to reduce the effectiveness of the immune system—in the case of cold sores it can no longer keep the virus Herpes simplex under control which results in re-activation of the infection.”
Hence, when it comes to cancers, sunlight can deliver a devastating one-two punch. First, by directly provoking DNA damage and then by reducing the immune system’s natural ability to deal with such damage.
Wisely, we need to take precautions so that we do not overexpose ourselves to the sun. Our health, and indeed our very lives, may be at stake.HOW
▪ Limit your exposure during the midday hours between 10:00 a.m. and 4:00 p.m., when UV radiation is particularly intense.
▪ Try to stay in the shade.
▪ Cover your arms and legs with tightly woven, loose-fitting clothes.
▪ Wear a wide-brimmed hat to protect your eyes, ears, face, and the back of your neck.
▪ Good-quality wraparound sunglasses, or sunglasses with side panels, that provide 99 to 100 percent UVA and UVB (categories of ultraviolet light) protection will greatly reduce the risk of eye damage.
▪ Use—and liberally reapply every two hours—a broad-spectrum sunscreen with a sun protection factor of at least 15.
▪ Since sunlamps, sun beds, and tanning parlors use UV radiation, which may damage the skin, WHO recommends avoiding them.
▪ Be careful to protect babies and young children, whose skin is particularly delicate.
▪ Never fall asleep in the sun.
▪ If you develop a mole, a freckle, or a spot that you are concerned about, see your doctor.
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