Sun science

What's new under the sun

Sun Science
What’s new under the sun

Before you roll your eyes at yet another story on the same old evils of the sun, stop! Trust us, there is something new to tell you. After all, keeping pace with the complicated science of sun protection is like keeping up with the romantic entanglements of a Hollyood starlet. Don’t believe us? OK, quick quiz: why is ozone depletion, which allows more and more ultraviolet rays to penetrate our skin, increasing even though harmful emissions are on the decline? And what is the new minimum sun protection factor recommended by doctors?

Knowing the answers to those questions is essential to preventing not only prematurely aged skin but also skin cancer – a disease that is on the increase. In fact, since 1990 the number of cases of malignant skin cancer has grown by more than 20 percent, making it the most commonly diagnosed cancer in Canada. So, read on for the answers to those important questions –and don’t wait until it’s too late to put them into practice.

Sun protection: the latest
We’ve known for a while now that we have to wear sunscreen every day – even on cloudy days – and beauty companies have spent considerable time and resources developing technologies that will allow them to create effective sun-protection products that you’ll want to put on daily. New technology, for example, has rendered particles of titanium dioxide and zinc oxide (still considered to be the primo sunblocks) smaller than ever (a process called micronizing) so sun protection can be blended into everything from moisturizers to foundations, making those opaque, chalky streaks of zinc oh-so passé.

Other innovations are also responsible for a new generation of clear sprays boasting an SPF of 30. “Up to now, it’s been really hard to put things together in the lab so they remain stable,” says Toronto dermatologist Dr. Lisa Kellett of DLK on Avenue. “With sprays, we had managed up to SPF 15, but few manufacturers could do better than that. Now I’m starting to see more [clear] sprays at a higher SPF.” 

That’s a big deal, says Dr. Kellett, because “it doesn’t matter how great a product works if you can’t get a patient to wear it.” Now anyone prone to acne or oily skin can avoid greasier cream-based formulations thanks to these sprays with amped-up SPF.

Look for broad-spectrum protection
Chemists have also been hard at work improving compounds so they absorb deep-penetrating UVA rays as efficiently as UVB rays, which can burn you superficially. “Ultraviolet rays are comprised of different wavelengths,” explains Dr. Ana Rossi, medical director of aesthetic dermatology and dermatology for Johnson & Johnson (makers of a variety of sunscreens, including RoC and Neutrogena). “And a truly broad-spectrum sunscreen is one that absorbs the two wavelengths that penetrate the skin: UVA and UVB.”

A couple of new chemical screeners block a greater range of wavelengths than ever before: from RoC comes Tinosorb M and Tinosorb S – which are photo-stable, a chemistry term that means the filters don’t degrade under exposure to light until after many hours of sun exposure. And just as stable is L’Oréal’s Mexoryl XL, which, when combined with its predecessor, Mexoryl SX, balances the broad-spectrum scale of protection. Note: even though these products are photo-stable for many hours–six hours for Tinosorb M + S – reapplying your sunscreen every two hours is recommended, as perspiration and your clothes rubbing on your skin decrease your level of protection.


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Damage control
Also making waves in sun-protection circles is sunscreen’s newest friend, antioxidants, such as vitamins A, C and E, green tea and selenium. Critical for skin repair, blending antioxidants into the SPF mix gives the modest sunscreen true antiaging status.
“The Europeans started this push by promoting products that not only protect the skin from sun but also reverse free-radical damage [due to previous sun exposure],” says Dr. Kellett. Now, a number of North American companies are climbing aboard the antioxidant wagon. Dermalogica, for example, has come up with a new line containing UV Smart Booster Technology, which involves antioxidant vitamin capsules that, when hit by sun, get straight to work on helping your skin cells. How? “When skin is burned by the sun, some of the cells on the skin’s surface burst open and the cellular membranes simply erupt, leaking the contents of the cells,” explains Leanne McCliskie, education manager at The International Dermal Institute in Toronto. Meanwhile, those insidious ultraviolet rays are stimulating equally insidious free radicals, which invade and undermine other cells. This is when the sun-activated antioxidant capsules give a much-needed boost to those skin cells that are unable to repair themselves.

A tan by any other name is still a tan
Among the new breed of sun-protection products, the most hotly debated is a lotion that claims to act as a “sun vaccine” by stimulating the skin to produce more melanin, “the body’s built-in sun protection factor.”

But what dermatologists such as Dr. Kellett want consumers to understand is that melanin only offers a limited sun-protection factor of less than 15. “Even the blackest of skins – skin with the most melanin – are in danger of ultraviolet damage,” says Dr. Kellett. “Melanin offers very little protection, so this notion of boosting the amount of melanin really provides a false sense of security.” Adds McCliskie: “When melanin is stimulated [by sun exposure], so are the free radicals that damage healthy cells. It’s a double-edged sword.”

And that double-edged sword is even more likely to cut into your life if you’re a tanning-bed user. Here’s an inconvenient truth: a 2003 University of Oslo study reveals that people who use tanning beds, even moderately, have a 55 percent increased risk for skin cancer. Are those odds you really care to gamble on? Further, Alan Geller, associate professor of the department of dermatology at Boston University, completed a study in 2002 that shows that tanning-bed usage among girls doubles from age 14–15, then doubles again at age 17–and DNA damage in your teens can cause cancer later in life. What they likely don’t realize, says Geller, is that 30 minutes in a tanning bed results in three times the UV exposure as the equivalent amount of time in the sun. If you must have golden skin, opt for bronzers and self-tanners, but that doesn’t mean you can skip safeguarding your skin. “We have data to demonstrate that people who use sunless tanners are more likely to burn than those who don’t use them,” says Geller. Bottom line? Don’t mistake a tan, whether from a bottle or a tanning bed, as any sort of protection from the sun. 


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Application 101
?Visualize a golf ball as you squirt sunscreen into your palm–that’s about how much you should be applying to your entire body. According to a 2004 Johnson & Johnson study, most of us miss the mark big time, applying about one-third that amount.

?Give every inch of skin equal attention. The same study reveals that our application techniques are patchy at best – we tend to apply more on our shoulders, forearms and the tops of our thighs and less on our back, the backs of our legs and the perimeter of our clothing. And since skin cancer is an equal-opportunity killer – it doesn’t prefer one area of the body over the other – whether you’re spraying or slathering, even coverage is essential.

The bare minimum
We all know that chemicals such as CFCs and pollution have damaged the ozone layer, allowing harmful UV rays to make their way down to earth. In fact, since the late 1970s, the ozone has reduced about six percent, despite recent curbs placed on emissions and pollution. How does that relate back to your skin? That six-percent reduction in ozone may seem like pocket change, but it translates into a seven percent increase in UV penetration over most of Canada, which is why, in large part, most dermatologists are now recommending a minimum SPF of 30 every day.


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