This week the New York Times scooped the Fat Finch. That is probably why having prosperous newspapers is a good thing. No blogger, however good, can be expected to think of everything and get it on a blog before a major newspaper. They wrote about sun screen even though we had this post about ready to post. The nerve.
But why, you may ask, does the New York Times care about sun screen? Why, you may ask, is this birding blog writing about sun screen? You may even be saying to yourself, “Give me one good reason why I shouldn’t stop reading right now!”
Wait! Here is the reason: Skin cancer is a bad thing, you don’t want it, and we’re about to tell you how not to get it while you are out with the birds. Besides, you may have noticed that you can now buy sun screen with a SPF rating of 100. Perhaps you have wondered if that isn’t marketing overkill on the part of the manufacturers of sun screen. To find out the answer you either have to read to the bottom of this post or go read the New York Times article which will take you longer to read and be troublesome.
We begin with those SPF numbers, SPF standing for “skin protection factor.” Don’t be fooled into thinking those are objective or accurate numbers. They are simply estimates of how much longer you can stay in the sun without getting a sunburn if you have properly applied the sun screen. So, if you go out at high noon and would normally begin burning in about 30 minutes, you can remain in the sun without burning for about 7 hours without burning, if you have SPF 15 sun screen properly applied. Unless you sweat a lot of it away and you will.
So, if are a fair-skinned, freckled red head and normally start burning after 10 minutes in the sun, SPF 15 will protect you for about two hours. On the other hand, if your skin is darker and you can stay out for two hours without burning exposed skin, you are protected for the entire day, assuming the sun screen is not washed out by sweat or water. For you, SPF 100 is definitely overkill. You could stay out for 200 hours if the stuff lasted that long.
But nothing in life is really that simple. The SPF estimates only tell you about ultra-violet B ray (UVB) protection while telling you nothing about the ultra-violet A (UVA) rays the sun also emits. UVB rays are the cause of sunburn. UVA rays are the ones that are aging your skin which, by the way, is your body’s largest organ. That is why you need to use a sun screen with either avobenzone or mexoryl sx in it. They provide some protection from UVA rays.
Of course, most birds have the good sense not to be very active when the sun is high. That is why birders get up early to spot them. Or stay out until the hour before and the hour after sunset. At those times, the sun’s slanted rays are less harmful and the need for protection is less. If you are not going to be out in the middle of the day, exposed skin certainly needs no more than SPF 30.
But it must be applied properly. That means an ounce if you are covering your entire body. That means a thick application on your face, ears, neck and hands if you are wearing long pants and long sleeves and a hat. And that is the best of all. Which only one of us ever seems to do. Guess who.
For more information, here is the FDA’s information page about sun screens.