June 1, 2012 at 4:40 PM ET
While "tan mom" Patricia Krentcil’s skin illustrates what happens when a person chronically fake bakes, accidental exposure to sunlight can cause as many wrinkles without a person even being aware of it.
An unnamed 69-year-old man visited doctors at Northwestern University and with wrinkles etched into the left side of his face -- the lines are so deep that the left side looks as if it belongs to a man 20 years older, while the right side seems age-appropriate. The startling image appears in a recent issue of the New England Journal of Medicine.
The man worked as a delivery truck driver for 25 years, and over time, the UVA rays shining through the truck window caused severe wrinkling and over-aging. UVA rays, or long wave ultraviolet rays, account for about 95 percent of the UV radiation reaching the Earth from the sun, according to the Skin Cancer Foundation. UVB rays, or short-wave ultraviolet radiation, cause the red blistering of sunburn, and though these rays do not penetrate as deeply as UVA rays, they contribute to the development of skin cancers.
Physicians call these deep lines caused by overexposure to UV rays dermatoheliosis, though most people know it as photoaging, the wrinkling and cracking of skin caused by too much time in the sun (or the tanning bed). During the 25 years the man drove his truck, the UVA rays hitting his skin damaged the epidermis and upper layers of his dermis, where collagen is. Collagen helps make the skin elastic and prevents such crevasses.
Repeated exposure to UVA rays also thickens the stratum corneum, the outermost layer of the epidermis, which protects the body from infection, chemicals, and environmental stresses. This toughening is the body’s way of attempting to protect itself from sun damage.
The physicians, Dr. Jennifer R.S. Gordon and Dr. Joaquin C. Brieva of Northwestern University, note that the driver most likely was exposed to UVA rays, which are less likely to cause cancer than UVB, but do play a role in skin cancers.
"I see photoaging and photodamage every day in clinic, but not so starkly demarcated," Gordon said via email. "Otherwise we typically see symmetric damage. Interestingly, there are some differences in which side of the body skin cancers occur more often on that some people think are attributed to driving habits because they vary based on country, gender, passenger/driver, etc."
The doctors recommended treatment for the driver that involves monitoring him for the development of cancer and prescribing a topical retinoid, which may erase some of the damage. Most people can easily prevent photoaging by slathering on the sunscreen and wearing protective clothing and hats (even if you think you’ll be shaded).