As I mentioned earlier this week, the debate over sunscreen safety appears to intensify each summer. In Part I of our Sunscreen Safety Series, I address the issue of nano technology; specifically, nano zinc oxide and nano titanium dioxide.
Today, I'm going to tackle another highly controversial topic: Whether sunscreen actually reduces your chance of skin cancer or, even worse, if it actually increases your risk! Since consistent, straight answers to these questions are harder to find than a flattering boy-shorts bikini, I once again turned to the current body of research on the topic. Sure, research isn't without its (often significant) limitations, but I trust science more than I trust some random dermatologist who happened to answer his or her phone when a beauty editor from whatever magazine happened to call.
Before discussing the science on this one, I should mention I am not a sunscreen evangelist, insisting that everyone apply sunscreen before so much as walking to the end of the driveway to fetch the day's mail. I'm not ready to accept that we're one leftover can of Aqua Net away from requiring futuristic, UV-proofed bubble cities to survive. Close, maybe, but not quite yet. Our bodies need sun, it would seem, and Vitamin D in particular. I operate from the basic belief that we were designed to survive in nature, which obviously includes the sun. Yes, we have done damage to our atmosphere, making the sun's rays more dangerous. And yes, our skin is way wussier than in previous centuries, since most of us don't spend much time outside. But are we sure sunscreen is the panacea for all that may burn us?
Here's what I found while digging through this year's pile of scientific updates:
When it comes to sunscreen's ability to protect us from skin cancer, I think the EWG Sunscreen Report does a particularly good job summarizing the existing body of research, so let's start there:
Studies of frequent sunscreen users have found a lower incidence of squamous cell carcinoma, a slow-growing tumor that is readily treatable by surgery, compared to people who use sunscreen infrequently or not at all. But scientists’ conclusions are mixed on whether sunscreen use can avert the deadliest form of skin cancer, melanoma. A newly published study of a group of sun-savvy Australians found that the daily use of a SPF 15 sunscreen with good UVA protection along with other protection strategies reduced risk of melanoma diagnosis over a 10-year follow-up period (Green 2011). But other studies have concluded that sunscreen users are at increased risk of melanoma because they tend to subject themselves to more intense sun exposure (Gorham 2007). No one has the final answer.
Some studies suggest that using suncreens may give people a false sense of security. Users may stay out in the sun longer and be exposed to more radiation overall. Scientists also speculate that substances called free radicals, produced in skin when sunscreen chemicals break down in sunlight, may themselves promote cell damage and contribute to skin damage and cancer.
Another hunch: Inferior sunscreens with poor UVA protection, which have dominated the market for 30 years, may have led to this surprising finding.
The conflicting scientific findings have divided the experts, with some questioning whether sunscreens do anything to prevent skin cancer of any kind. Studies focused on the better, broad-spectrum sunscreens on the market now won’t be published for years.
As it stands, many experts agree that there is no solid proof that sunscreens protect against skin cancer.
The FDA takes the position that “To date, there are no clinical studies demonstrating that use of any sunscreen alone can prevent skin cancer.” (FDA 2011)And then there's the research suggesting certain chemicals in many sunscreens, including very recent research implicating zinc oxide, may potentially increase one's susceptibility to skin cancer by releasing free radicals when exposed to the sun over long periods of time. Unfortunately, few of your alternatives are any better, since other common chemical sunscreens like oxybenzone pretty easily find their way into the bloodstream, and are linked to hormone disruption and allergic reactions, with no obvious benefits to outweigh the potential risks. And then there's research suggesting Vitamin A - also found in many sunscreens as Retinyl palmitate - may actually increase the speed at which malignant cancer cells spread throughout the body. (Side note: What I find more troubling is the likelihood the FDA knew about this link for years yet stayed mum about it because, as I've learned over the past few years, they have neither spine nor teeth. Think of them as government-sponsored jellyfish.)
My conclusion? If you want to be 100% safe from the sun's potentially harmful rays, either stay out of the sun or use UV protective clothing. If you've just gotta feel the sun on your skin, then it's a Pick Your Poison kind of a deal. That is, unless you live in, or are visiting Europe, in which case I might suggest stocking up on their cornucopia of better options. Otherwise, opt for a mostly natural, oxybenzone- and retinyl palmatate-free sunscreen with an SPF of 15-45, and be sure to apply evenly and everywhere if you're going to be out in the sun for an extended period of time. I wouldn't waste your money on SPF9000+, since any SPF rating over 50 is meaningless and misleading, which is why the FDA technically banned this labelling practice in 2011. Predictably, they recently announced the new labeling rules won't be enforced until some time after this summer because, well, because of the whole Federal Jellyfish thing.
Which brings me to my last bit of advice: Avoid perfection when selecting sunscreen. I say this because I care about your sanity. Research studies on the safety of ingredients always comes after the products are on the market and hugely successful, so you are unlikely to find unbiased information. The FDA appears to be underfunded and/or uncertain of its job description, so they are of little help. You may not be able to get it 100% perfect, but if you follow the general guidelines set forth by the EWG's Annual Sunscreen Reports, you probably won't get it horribly wrong, either.