When I was a kid, the only bad thing about sunbeams in the spring was getting a sunburn from being exposed too long on those first few warm days. There was no thought of staying out of the sun, keeping ourselves lubed up with sunscreen or wearing clothes to prevent the sun from getting to our skin. The goal was to get a little sun one day, a little bit more the next and the next until we obtained our “summer tan.”
We didn’t realize there was a long term affect on the health of our skin. Sure, it was simple to see older people who worked outdoors most of their lives had different looking skin than similarly aged people who worked indoors. It wasn’t until the early 1970s the link between long term exposure to the sun and skin cancer was definitively proven.
Oddly enough, sunscreen “potions” had been around for more than thirty years, by then. Coppertone was the first commercially successful product, gaining popularity in the 1950s. Then, it was not called sunscreen as today’s versions and other lotions are termed. It was suntan lotion, a mixture of ingredients which would reduce sunburn, promote suntans and supposedly keep regular users from looking like grizzled cowboys in their senior years.
After the sun-exposure/skin cancer link was exposed, the sun protection industry boomed.
Hundreds of products, mostly lotions, which purportedly protected human skin from the ravages of solar radiation quickly filled store shelves. To read the marketing hype on some of these products, they were shade in a bottle. Whether sunscreen was a health product or cosmetic product made no difference since the government (Food and Drug Administration) already regulated both of these. So a standard was developed to help consumers compare the various elixirs, a standard called SPF for Sun Protection Factor.
The original goal for most sunscreens was to attain an SPF of 15. This number was chosen because it would allow a person to be in the sun for 15 hours and only get about one hour’s worth of UV radiation. In most parts of the world, that means dawn to dusk protection.
Then both science and mythology took over. Some of the magic potion, however would wash off, wear off or otherwise become ineffective. So scientists invented sunscreen which was waterproof, among other things. It wouldn’t wash away while swimming or sweating, or so the advertisements claimed. Good idea, but a better idea is to just reapply every hour or two remain effective.
Mythology in this case means marketing. If SPF 15 was good, wouldn’t SPF 30 be better? Wouldn’t SPF 50 beat out 30? Slather some on your face on Monday and you were good until Wednesday — except for sweat, swimming and showering.
Better to just put on a long sleeve Tee shirt and make sure the sunbeams don’t get to that tender skin, right? Wrong, they say now. Harmful UV rays can penetrate through (some) types of fabric — like most white Tee shirts. A white cotton Tee would have a SPF of 5 — still better than bare skin. A dark denim shirt would offer an SPF of about 1700.
When it comes to clothing (or fabric) it’s not SPF, it’s UPF. The FDA didn’t regulate clothing so a bevy of federal agencies — starting with the Federal Trade Commission came up with their own vernacular — Ultraviolet Protection Factor.
More and more people are shunning “chemicals” in favor of clothing designed to be “wearable” shade. It’s now an industry with every major player in the outdoor world now marketing “performance” wear with varying UPF numbers. So what to look for in a number?
As with sunscreen and SPF, bigger numbers provide (slightly) more protection. A UPF shirt with a number of 15 blocks 93 percent of the UV radiation coming from the sun. Move up to UPF 25 and you gain three percent more. That shirt will block 96 percent. Pay twice the price for a UPF 50 (that’s max) and gain two whole more percent protection.
I’m not arguing for or against any potion or fabric designed to protect people from sunburn now or skin cancer later — better safe than sorry. But don’t put your faith in the number system designed by government regulators. The benefit of choosing a higher UPF or SPF number is hard to measure. The cost of choosing a that higher number is easy to count.