Last month, I received a health-scare email from my mother-in-law. In it, she explained that her doctor had removed a "spot" on her face, and a biopsy revealed that it was neither benign nor malignant, but pre-cancerous. Her doctor told her she could have the spot surgically removed or he could carve the surrounding tissue away right then and there. She chose the latter, leaving her with a sizable scab on her right temple and a slightly blackened eye.

The really cool part, she explained, was the treatment she would receive after the scab and skin healed. Called blue-light therapy, the treatment would zap any lingering pre-cancerous cells. It would also lighten age spots and a lot of the sun damage she had accumulated over years of seeking the perfect tan. It would smooth a few wrinkles and give her facial skin an all-over, regenerative boost. Clearly, she was looking on the bright side, making the best of a scary situation.

Dr. Nancye McCowan, a dermatologist at the University of Mississippi Medical Center, confirmed the efficacy of FDA-approved photodynamic or blue-light therapy for pre-cancerous "actinic keratosis." Doctors inject or apply photosensitive chemicals to the skin and then activate them with a specific range of light. The chemicals and light not only destroy the pre-cancerous cells, they allow medical professionals to identify other harmful cells that were previously undetectable.

Now, I confess: I, too, have been a sun-worshipper for most of my life. In the last few years, however, I'm no longer capable of spending hours in the sun. It feels hotter somehow, and I don't enjoy sunbathing anymore. According to an article in scientificamerican.com, the radiant heat our planet receives from the sun is not venting properly. Like too many covers on a warm night, gaseous pollutants—primarily carbon dioxides—form an insular blanket around the earth, trapping the sun's heat near the planet's surface. But heat is not really the issue.

The real threat to the health of the largest organ of our bodies—our skin—is exposure to potentially harmful ultraviolet A (UVA) and ultraviolet B (UVB) radiation. Sun Protection Factor, or SPF, has been around on sunscreens and tanning lotions since the mid 1960s. Nevertheless, the incidence of nonmelanoma, the most treatable form of skin cancer, is on the rise.

Skin cancer is the world's most common form of cancer, reports the Skin Cancer Foundation website, skincancer.org. "There are more new cases (of skin cancer) annually than the combined incidence of cancers of the breast, prostate, lung and colon," an article on the site states.

Luckily, most non-melanoma skin cancers are highly treatable with early detection. But don't take them lightly. Skin cancers have a high rate of recurrence—if you are diagnosed once, there's an increased risk of developing another cancerous growth, including melanoma, the life-threatening form of skin cancer.

Our best line of defense: hats, protective clothing and sunscreen on exposed skin. McCowan recommends using a broad-spectrum sunscreen, one that filters both UVA and UVB with a minimum rating of SPF 30. After an hour and half to two hours—less when swimming or sweating—reapply.

The recommended amount of sunscreen to cover the average adult is one ounce, enough to fill a shot glass or the palm of your hand. Apply it 30 minutes before you go out in the sun so the protective ingredients can properly attach to the skin.