Sun Protection Factor—SPF

It should be noted that the SPF—Sun Protection Factor—listed on sunscreen products indicates how much longer you can stay in the sun without burning compared to not having sunscreen. If your skin is unprotected, and burns after thirty minutes, a product with an SPF of 10 would mean you could stay in the sun ten times as long, or five hours. Using that same product a few times during your stay in the sun will not prolong the protection—you would actually need to use a sunscreen with a higher SPF to accomplish this. Sunscreens with an SPF of more than 30 may not offer any additional protection, despite the marketing hype.

Humans have lived in hot, sunny environments for tens of thousands of years. While most athletes spend considerable time outdoors, it’s important to not abuse the skin. The concern, however, is that increased sun exposure can cause dry skin, wrinkles, and, the greatest concern, skin cancer. Certainly skin damage and the risk of cancer are possible if time spent in the sun is abused, especially at an early age and when one is not healthy.

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Not until the past few decades has the incidence of skin cancer become a growing problem. This period corresponds with the development of sunscreen and other products that attempt to block the sun’s rays. Vitamin D is known to prevent many cancers, including skin cancer. William Grant, PhD, who has published many papers on this topic, says that sunscreen is overrated and gives a false sense of security. Other research shows the use of sunscreen can actually increase the risk of malignant melanoma (the most common and deadly form) and other skin cancers. Grant and other researchers describe the problem this way: Most sunscreens block UVB (ultraviolet B waves) very effectively, which is what we make vitamin D from, but sunscreen does not block longer waves that are more dangerous, such as UVA, well. We obtain vitamin D through UVB, and if we block that wave, our sun-stimulated vitamin D production is reduced. And, users of sunscreen often remain in the sun longer because of its artificial comfort. But they are unwittingly exposing their skin to more dangerous UVA and increasing the risk of skin cancer. For this and other reasons, the growing list of research supports the notion that we can prevent a significant number of many types of cancers by spending some time in the sun, without sunscreen—as long as we don’t burn.

Some studies show a relationship between sunscreen use and cancer prevention while others have not. Still other studies show sunscreen use can actually increase the risk of malignant melanoma. Unfortunately, sunscreen manufacturers and cosmetic companies spend millions on marketing, using popular scare tactics to convince people to use their products.

For most of my career, I have recommended getting a good tan to protect the skin against excessive sun damage. In fact, tanning provides protection similar to sunscreen, and with protection specifically against the potentially dangerous UVA. A recent issue of Science (March 2, 2007) says the same: “A dark natural tan offers unparalleled protection against skin cancer.” Not everyone can tan. Extremely fair-skinned people, those with red hair, and those with freckles can burn quite easily, and these individuals must be cautious when outdoors.

My advice has always been the same: Don’t put anything on your skin you’re not willing to eat! That’s because sunscreen, along with so many things people put on their skin, gets absorbed into the body.