Saturday, July 4, 2009

Choose the Right Sunblock This Summer

By Kevin Purdy

Even if you're truly light-skinned, buying an expensive sunblock with a super-high SPF rating won't really protect you much more than a standard brand. Putting enough of that goop on is what really counts.

Photo by Robert S. Donovan.

Because the U.S. Food & Drug Administration had considered capping SPF claims at a level of 50, but has yet to take action. The reasoning holds up, however—even 100+ SPF sunblocks can't offer 100 percent protection against both UVA ("aging" rays) and UVB (the sunburn kind). And everything North of SPF 30 is just a numbers game:

The difference in UVB protection between an SPF 100 and SPF 50 is marginal. Far from offering double the blockage, SPF 100 blocks 99 percent of UVB rays, while SPF 50 blocks 98 percent. (SPF 30, that old-timer, holds its own, deflecting 96.7 percent).

Aside from scolding the sunblock makers, the New York Times article linked below offers an important take-away visualization:

To get the SPF advertised, you must use a full shot glass on your body. That's an ounce, which means a three-ounce tube should last, at most, a few outings. ... "If people are putting on about half, they are receiving half the protection," said Yohini Appa, the senior director of scientific affairs at Johnson & Johnson, of which Neutrogena is a subsidiary.

Bottom line: Find a sunblock that offers a decent SPF protection, contains UVA-fighting agents like avobenzone, put a full shot glass on your exposed body, and reapply every two hours or after noticeable sweating, or swimming.