If you've been following this blog for a while, you've endured, shall we say, a few bad puns. So I am guessing you can endure one more.
Here goes: Sunscreen is a sensitive issue for me.
Actually, it's not as much of a pun as it might seem because, well, my skin is sensitive. I have always known as much, and a few doctors (including my primary care physician and the orthopedic surgeon who treated me after I was "doored" in October) have confirmed it. Some of that sensitivity has to do with my melanin deficiency: I burn easily.
So I pay attention to the labels on my suncreen. In addition to being alert for chemicals that don't sound as if they should be applied to any part of my body (and that, in microscopic amounts, can damage coral reefs as well as other marine life), I also look at the number almost everyone else checks: SPF. A higher-number SPF gives you more protection; I've been advised to use a 50. When I went to Cambodia and Laos three years ago--my second trip in the tropical zone--I packed a 100 SPF sunscreen.
While a higher number does indeed offer more protection, one-third of all sunscreens Consumer Reports recently tested actually had less than half of their claimed SPF. Moreover, some experts cite the law of diminishing returns: Any increase in SPF over 50 offers less of an improvement in protection than any increase up to 50. That argument is based on the fact that a 50 SPF sunscreen offers protection from about 98 percent of Ultraviolet B (UVB) rays: the ones that burn the surface of our skins. (Ouch!)
But SPF ratings don't tell us anything about a sunscreen's ability to protect us from Ultraviolet A (UVA) rays. Those are the ones that penetrate the skin and lead to premature aging. In the European Union, all sunscreens have to offer at least a third as much UVA as UVB protection.
Thoug both kinds of ultraviolet rays contribute to skin cancer, B plays a greater role, espcially in malignant melanoma, the deadliest form of the disease. The good news is, of course, that a sunscreen with 50 USB or more will protect from most of the harmful rays--that is, when it's used properly. The American Academy of Dermatology recommends using enough lotion to fill a shot glass (two tablespoons), more if you're a larger person.
The AAD also prefers traditonal lotions over spray-on because the latter disperses the sunscreen into the air. When you apply a lotion with your hand, more of it ends up on your skin. And, sprays are generally a bad idea for sunscreens as well as any number of other products because the chemicals used as propellants are bad for the environment as well as your lungs. (Even if you can't smell it, you're likely to inhale droplets of those chemicals, as well as the rest of the sunscreen, when you spray it.) And, finally, the AAD "sunscreen pills" are basically snake oil.
Whether you're like me, or darker, you should be using sunscreen when you're out for half an hour or more--even if you're covered up. (UVA and UVB can penetrate fabrics.) At the end of your ride, the burn you feel should be in your muscles, not on your skin.