Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...Tell Me More
As you may know, I’m not a huge fan of sunscreen lotion. I just don’t think it’s all that necessary. If you’ve had enough Vitamin D skin production for one day, and you’re worried about burning up, using physical barriers – like shirts, hats, umbrellas – to impede the sunlight is better than slathering your skin with powerful chemicals. Still, in the event that the only thing standing between you and a second-degree sunburn is the application of some lotion, have at it. Just be aware that, according to a recent NY Times piece, there is some seriously misleading marketing lingo circulating in regards to SPF counts.
Wait, wait, wait. You mean to tell me sunscreen companies don’t necessarily have my best interests in mind? That Coppertone, a company whose financial success is predicated upon consumers thinking those astronomical SPF numbers actually mean something substantial, might be fudging the numbers a bit? That 90+ SPF product from Banana Boat isn’t actually more than twice as powerful as their measly 45 SPF sunscreen?
Frankly, I am shocked. Shocked and appalled. That just doesn’t sound like the Neutrogena, Coppertone, and Banana Boat, I know. These are fine, upstanding stewards of public dermatological health. Why, I’ve seen their pasty, alabaster-hued patrons buying cartons of the stuff in checkout lines, so it must be working (sure, they may have frighteningly low Vitamin D levels and brittle bones like elderly hummingbirds, but the evil sun can’t touch them!). I mean, c’mon: what could possibly compel a sunblock company to misrepresent the effectiveness of their products? It’s not like they would ever exploit our natural tendency to assume that a linear progression in SPF numbers represents a commensurately linear increase in protection from the sun. Plus, the higher SPF products tend to cost a lot more than their lowly counterparts, and we all know that the pursuit of profit never conflicts with the pursuit of all that is good and right, especially when large, multinational companies are involved – so that’s not possible. So – is it really true that the sunscreen companies are padding their stats?
Sadly, yes. 100 SPF doesn’t actually offer twice the protection of 50 SPF; the former blocks 99% of UVB rays, while the latter blocks 98%. I was no math major, and I could be mistaken, but 1% doesn’t sound like twice the protection to me. Even a sunscreen with an SPF of 30 will still “protect” you from 96.7% of UVB rays (but don’t’ expect them to put that on the package anytime soon!). At the same time as you get diminishing returns with added SPF, inadequate amounts of sunscreen result in precipitous drops in protection that fly in the face of public assumptions. Take SPF 70 lotion: if you apply half the recommended amount, the resultant protection is equivalent to SPF 8.4, not SPF 35. As you get higher in the SPF scale, the returns get smaller and smaller; as you apply less lotion, the protection sharply drops off (of course, the recommended amount often amounts to a third of the bottle!). It almost seems like the rating system, as it exists now, isn’t used to indicate protection as much as it’s intended to make consumers feel “like SPF 45 is inadequate.”
While the higher SPFs technically do offer more protection, the implied advantage is clearly overblown, and customers – their heads filled with horror stories of melanoma developing overnight after a few scant hours of unprotected sun – are generally going to go for the biggest numbers. The number 100 is twice as big as the number 50, and SPF 100 sounds twice as strong as SPF 50. Simple, basic math is anything but simple and basic when it comes to SPF.
It’s well within the sunscreen company’s purview to mislead and misdirect the hapless consumer, but hopefully those same consumers will happen across articles like this one or the NY Times’ before they get suckered in.