Q: I’ve read a lot lately about the benefits of sun-protective clothing. Is there really such a thing and if there is, what’s the difference between that and just plain old clothes?

A: I have to admit, the first time I heard about clothing with an SPF in it, I thought it was a hoax. I mean, what did they do? Smear Banana Boat all over a T-shirt and market it is as SPF 30 or whatever? But I must admit, since I’ve learned more about it, I have become a believer.

Sun-protective clothes were first popularized in Australia (those sun-loving Australians, they think of everything) back in the '90s. The concept made its way to the U.S. by 2001. How do we know it works? The clothing goes through a rigorous testing process that tests the durability, washability and effectiveness of the product. At the end of the testing process, the clothes are then assigned a UPF factor.

UPF, unlike SPF, measures protection against both UVA and UVB rays. Right now, on sunscreens sold in the U.S., the SPF is the only measure of protection listed, and that only measures the sunscreen’s protection against the sun’s UVB rays. Protection against UVA rays is not currently listed on the label, and those rays are just as dangerous as UVB rays. (Labels are scheduled to change in 2012.)

That’s why sun-protective clothing, with a UPF rating that measures the protection you’re getting from both UVA and UVB rays, may be even more effective at preventing damage from the sun’s rays.

So what’s in these magical clothes? Not only are these clothes often made from a tighter fabric weave and darker colors — sun-protective clothes are also treated with sunscreen chemicals that absorb the sun’s UV rays.

So what’s wrong with regular clothes? Well, it depends. While it is true that tightly woven, dark clothes can provide some protection from the sun, it is not clear how much. For example, a white T-shirt may have a UPF of only 5, which means that it lets in 1/5 (or 20 percent) of all UV radiation through to your skin. Sun-protective clothing that has a UPF of 50, though, and only lets in 1/50 or 2 percent of the sun’s UV rays, offers much more protection. So it might be beneficial to have some clothes that have been treated with sunscreen.

Don’t want to break the bank this summer and buy a whole new wardrobe of clothes? You could try Rit’s SunGuard. SunGuard is a laundry additive that you simply stick in a load of regular clothes that contains a sunscreen chemical called Tinosorb FD. The makers of SunGuard say that it doesn’t change the feel or look of your clothes at all, and they maintain their new UPF of 30 through about 20 washes. Sounds like a great option to me.

I especially love sun-protective clothing because my kids hate when I shmear sunscreen all over them. A hat like this one allows me to skip the sunscreen on their face (as long as they keep it on, that is).

Remember, though, sun-protective clothing doesn’t cover everywhere (unless you’re wearing Harry Potter’s robes), and you still need to apply sunscreen to your exposed body parts — i.e. your hands, feet and face. And don’t forget those ears!

— Chanie

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Does sun-protective clothing really work?
A tight weave and built-in sunscreen make these clothes the next best thing to being in the shade.