Summer snapshots suffering from overexposure?

Or is it just that the person in the photo looks overexposed? We've long been warned about overexposure to the sun because of its relationship to malignant melanoma and other less serious skin disorders. Recent studies show that this is not the only danger from excessive ultraviolet radiation.

Dr. Lorraine Kligman, research associate professor of dermatology at the University of Pennsylvania Medical Center, reports that ultraviolet radiation also poses a more general health hazard. "Ultraviolet radiation has an extremely adverse effect on the immune system by suppressing the function of specialized cells, called Langerhans' cells, which activate the system," she says.

As the first line of defense in the human immune system, Langerhans' cells act like tiny army sentries-- standing guard and assuming responsibility for detecting any foreign substance that comes into contact with the body. As soon as they perceive the intruder, they quickly signal other cells more suited to launching a counterattack. The suppressive action of UV radiation on these cells would, over the long term, make people more susceptible to any illness.

Dr. Kligman points to studies that confirm the adverse effects on the immune system of even so-called "harmless"UV radiation used in tanning salons. "The exposure people receive in tanning parlors is certainly not harmless," she emphasizes. "People receive the same detrimental effect to the immune system, and tumors have been produced in animal models."

This is not to suggest, of course, that we permanently shelve our swim wear and lock ourselves indoors. Sunshine is a wonderful morale booster--and its absence can have profound effects on the human psyche. The long, dark winters in the Arctic regions are known to cause depression, for example. Moreover, sunlight also helps to produce vitamin D in the skin, a factor particularly important to older people with poor diets.

So continue to enjoy the balmy, sunny days of early autumn--but protect your skin from excessive sunlight with suitable clothing. However, if sunbathing is your thing, use a sunscreen with a sun protection factor of at least 15.