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20 ultraviolet radiation and SPF facts that may surprise, even entertain.
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sunscreen true or false_Mullet Beach, St. Maarten

Mullet Beach, St. Maarten

Lovelies, I know you've been reading sunscreen stories for years, and I've posted a couple of sun-safety bits in a row already this season. But the topic is so complex that getting a handle on all the details is just freakin' hard! 

So I thought I'd do a round-up of True or False sunscreen details, including my new favourite fact, and as a reward for reading through them, offer the chance to win one of two sets of Coppertone's newest sunscreens, Clearly Sheer. (The giveaway is now closed.)

Okay, let's play! (Is it weird I really think of this as a geeky game?)

sunscreen true or false

sunscreen true or false_ombrelle_La Roche-Posay_Avene

Garnier Ombrelle SPF 60 Ultra-Light Cream for Face (fragrance and colorant-free); La Roche-Posay Anthelios SPF 50 Ultra Fluid Lotion (matte finish); Avène Very High Protection Mineral Lotion SPF 50+ for Intolerant Skin (great for pale skin)

1) The SPF number is the most important information on a bottle of sunscreen.

FALSE. The SPF number means only that there is protection against UVB rays that cause a visible burn on the skin. Not all sunscreen protects against insidious UVA rays that penetrate the skin more deeply and the bottles you buy must say broad spectrum on the label to indicate defense against UVB + UVA. Health Canada allows the use of a UVA logo as long as at least one third of the UV protection is made up of UVA filters such as Avobenzone, Oxybenzone, Mexoryl, Tinosorb, Helioplex, zinc oxide and titanium dioxide.

2) UVA rays makeup the bulk of UV we're exposed to every day.

TRUE. "UVB is only about five percent of the ultraviolet radiation that reaches the earth's surface; 95 percent is UVA," says Dr. Sonya Cook, dermatologist and co-medical director at Compass Dermatology in Toronto.

3) UVA rays go through windows.

TRUE. While ordinary glass blocks UVB radiation, it's little protection against aging UVA, so wear sunscreen if you sit in front of a window during the day and when you drive, too, or this could be you. Sure, your windows might be coated with a UV-blocking film, but unless you've had it done for your car or your all-windows condo, chances are they're not.

sunscreen true or false_spray sunscreen

La Roche-Posay Anthelios SPF 50 Ultra Light Mist; Neutrogena CoolDry Sport SPF 70 (its "Micromesh" technology allows sweat to evaporate off the skin without taking the sunscreen with it); Vichy Ideal Soleil SPF 50 Dry Touch Invisible Mist; Coppertone Clearly Sheer SPF 30 lightweight mist 

4) Most skin cancers are caused by UV radiation.

TRUE. The American Cancer Society states that "most skin cancers are a direct result of exposure to the UV rays in sunlight. Both basal cell and squamous cell cancers (the most common types of skin cancer) tend to be found on sun-exposed parts of the body, and their occurrence is typically related to lifetime sun exposure."

5) Tanning-bed users are at a higher risk for skin cancer.

TRUE. Also according to the American Cancer Society, "the risk of melanoma is higher if the person started indoor tanning before age 30 or 35, and the risk of basal and squamous cell skin cancer is higher if indoor tanning started before age 20 or 25."

Says Dr. Cook, "If I see someone in their 20s with melanoma, they almost always have a tanning-bed history."

Super-scary: "You can get a year's worth of UVA in just 20 seconds in a tanning bed," she adds.

6) The World Health Organization(WHO) has declared UV radiation is carcinogenic.

TRUE. The International Agency for Research on Cancer (IARC), an arm of the WHO, also classifies tanning beds as "carcinogenic to humans."

7) You only need sunscreen in the summer.

FALSE. While UVB (the sunburn rays) are weaker throughout the winter, UVA (the aging rays) are consistent year-round. 

Also noteworthy: in Canada, "the sun in April is as strong as it is in August," says Dr. Cook.

8) You don't need sunscreen when it's cloudy outside.

FALSE. "Clouds block infrared, the rays that feel warm on your skin," explains Dr. Cook. "UV rays are invisible – you can't see them and you can't feel them – and clouds block only 10 or 20% of UV."

sunscreen true or false_tinted sunscreen

Tinted sunscreens: La Roche-Posay Anthelios Mineral SPF 50 Ultra Fluid Lotion Tinted; L'Oréal Paris Sublime Sun SPF 50 Ultra-Light Finish Beauty Balm; Skinceuticals Physical Matte UV Defense SPF 50 Sunscreen; La Roche-Posay Anthelios SPF 50 Mineral Daily Tone Correcting Primer (fragrance-free, has blurring effect, Vitamin E and is designed for wear on its own or under makeup)

9) There's no such thing as a safe tan when it comes to UV exposure.

TRUE. Whether golden, bronze or red, any change in the skin colour as a result of UV exposure is a visible indication of UVB damage. As for UVA, that harm is invisible at first, then makes itself known over time.

10) UVB causes DNA damage.

TRUE. Aside from immediately evident injury such as a tan or sunburn, "UVB causes DNA damage that leads directly to mutations that can lead to skin cancer," says Dr. Cook. "UVA radiation results in the production of oxygen free radicals that can get into cell membranes and proteins and DNA." 

Tip: An antioxidant serum can provide back-up protection against free radicals caused by the small amount of UVA that gets past your sunscreen. Some sunscreens, such as Coppertone and Ombrelle, already contain antioxidants as insurance.

11) The most important factors in your sunscreen are its active ingredients.

FALSE. A sunscreen's film-forming components are just as important as the UV filters, says Stephen Baldwin, research and development expert for suncare with Bayer (they own Coppertone). 

"You have to think of the skin as a wrinkled surface. It has a texture, hills and valleys and creases – even young skin, although it looks smooth," he says. "To be effective, sunscreen needs to cover like a good paint, with a very even film, literally like a second skin to protect the peaks without puddling in the valleys. It has to be flexible and breathable and it has to be decently tenacious to achieve the necessary water-resistance for 80 minutes."

sunscreen true or false_stick sunscreens

Sunscreen sticks: La Roche-Posay Anthelios XL SPF 60 Stick; Sun Bum SPF 30 Sunscreen Face Stick; Neutrogena Ultra Sheer SPF 50 Face & Body Stick Sunscreen

12) Sunscreen is your first line of defense.

FALSE. Dr. Cook says it's your last. The first line of UV defense is avoiding the sundrenched hours between 10am and 4pm. After that comes hats, sunglasses, UV-protective clothing and limited exposed skin. 

"Putting sunscreen on so you can lay in the sun is a complete abuse of the product; they're not designed for that," she says. Really, you'll only be preventing blistering, not preventing possible cancer. "UVA protection still isn't as good as UVB protection, so you'll be getting way more UVA than you would have if you hadn't used sunscreen at all."

13) SPF as high as 100 was created by accident.

TRUE. "Sunscreen companies weren't trying for an SPF 100 – an SPF rating only addresses UVB, the rays that cause sunburn," says Dr. Julia Carroll, who is also a dermatologist and co-medical director at Compass Dermatology. "High SPF like 100 happened because formulators added really good UVA filters to protect against DNA damage. The combination of those improved UVA filters plus UVB filters resulted in a really high SPF number."

14) High SPF sunscreens mean you can re-apply less often.

TRUE. "They do buy you a little more time because sunscreens with chemical filters work like sponges," explains Dr. Carroll. "If you aren't in the sun, the protection will last longer." Still, you do want to get into the habit of reapplying sunscreen every two hours so that it becomes second nature.

sunscreen true or false

Neutrogena Ultra Sheer Dry Touch SPF 110; Ombrelle SPF 50 Sport Endurance; Sun Bum SPF 30 with Vitamin E; Aveeno Protect & Hydrate SPF 45 for face & body (contains skin-soothing oat extracts and oat proteins)

15) High SPF sunscreen compensates for human error.

FALSE. Studies show that people usually apply half or a quarter of the amount of sunscreen they need. But the level of protection they get isn't necessarily half or a quarter of the SPF number on the bottle – it's much, much less. 

"If people apply a quarter of the amount of SPF 60 that they should, they're getting an SPF of 3," says Dr. Cook.

So how much should you apply? You need 30 mL for the whole body (in bathing-suit circumstances), or "a teaspoon of sunscreen for face, a teaspoon per arm, two teaspoons per leg, a teaspoon for the back and a teaspoon for the front."

16) Oxybenzone, a chemical UV filter, disrupts human hormones.

FALSE. "In human studies, it doesn't have any effect on hormones," says Dr. Cook. "They've done the studies with putting huge amounts of sunscreen on and measuring the systemic absorbtion, seeing if there are any effects on hormones and there's no evidence of that."

sunscreen true or false_kids sunscreens

La Roche-Posay Anthelios Dermo Kids SPF 50 Face & Body; Alba Botanical Kids SPF 40 (moisturizing, fragrance-free, made with chemical UV filters); Garnier Ombrelle SPF 50 Kids 100% Mineral sunscreen (hypoallergenic, fragrance- and colorant-free)

17) Sunscreen in moisturizer and makeup isn't regulated.

TRUE, says Dr. Cook. "It's not a sunscreen, so it doesn't have to be broad spectrum. Even if they say SPF 15 or 30, they might have just one UVB blocker, usually Octinoxate, and then people think they're getting broad-spectrum protection and they're not."

Aside from the lack of regulation, you probably aren't putting on the amount you'd need – who applies a teaspoon of moisturizer or foundation? As well, you probably aren't putting it on your ears and other exposed areas the way you'd apply sunscreen. On top of that, anything below SPF 15 is classified only as protection against sunburn, not against skin cancer or premature aging.

18) Mineral sunscreens with physical filters are better for babies.

TRUE-ish. "Many people prefer those for their babies and that's okay as long as it's not their only defense," says Dr. Carroll. (Staying in the shade and wearing protective clothing are important too.) "Mineral or physical UV filters – titanium dioxide and zinc oxide – are broad spectrum, but in comparison to chemical filters aren't quite as good on their own at protecting against UV rays."

19) Sunscreen hinders your body's ability to create Vitamin D.

FALSE. To get your Vitamin D from sun exposure, you'd probably need only 10 minutes in the sun, three times a week, says Dr. Cook. Sunscreens don't block 100% of UV radiation, "so if you're going outside at all, data suggests you're getting enough UV to produce Vitamin D in the summer." 

In fact, an Australian study measured Vitamin D levels in people who used sunscreen all summer and people who didn't, and the levels were the same.

For Canadians in the winter, though, there isn't enough UVB to spark the production of Vitamin D, so we need a daily supplement anyway. "Also, people with darker skin, and elderly people just don't make Vitamin D as efficiently from UVB," adds Dr. Cook. "It's better to get Vitamin D from your diet."

20) If you work for a sunscreen company, walking in to work with a sunburn is Bad News.

TRUE. "Very rarely does anyone here get sunburn, because if they do, seriously it's a walk of shame," says Coppertone's Stephen Baldwin. "Every person they see, every meeting they're in, someone will crack, 'you know they make a product for that,' or 'you know how you can keep that from happening...' 

If you're out on the weekend and get a sunburn, rather than come in to work that way, it's better to call in sick."

coppertone clearly sheer giveaway  (closed)

coppertone clearly sheer SPf 30 sunscreen giveaway

New Coppertone Clearly Sheer SPF 30 Lotion, Clearly Sheer Face SPF 30 and Clearly Sheer SPF 30 Spray

SPONSORED GIVEAWAY (NOW CLOSED) • According to a 2013 Canadian Sun Care Protection Usage & Attitudes study, texture is the reason 51% of us skip sunscreen. No-one wants to cover his or her skin in a thick, sticky coating that also leaves white residue on clothing. Recent seasons have seen the release of more pleasing creams and lotions, and this year Canadians are meeting a brand new Coppertone formula.

The Coppertone Clearly Sheer broad-spectrum sunscreen collection has a lightweight texture that has been tested to ensure it won't clog pores or cause breakouts. Skin-conditioning ingredients include dimethicone, butyl maleate and Vitamin E. In addition, Coppertone Clearly Sheer Face SPF 30 and Clearly Sheer SPF 30 lotion for body both contain aluminum starch, octenylsuccinale, silica and styrene to give skin a smooth, matte finish.

As for the convenient Coppertone Clearly Sheer SPF 30 spray, it's a clean and light mist that leaves a matte finish on the skin too. 

Coppertone Clearly Sheer SPF 30 giveaway

Coppertone Clearly Sheer SPF 30 Face

Each Coppertone Clearly Sheer sunscreen format is waterproof up to 80 minutes, and has a light and fresh clean scent that can be used on sensitive skin. (When I used the spray on my 10-year-old niece, her immediate comment was "that smells nice, Auntie J!")

Wanna try them?

If you live in Canada (including Québec! Yay!) and have reached or passed your 18th birthday, enter below to win one of two sets of Coppertone Clearly Sheer sunscreen (value: approximately $30 CAd). 

Enter as many times as you like, and please do let us know in the comments which of these 20 true-or-false sunscreen factoids you already knew, which surprised you, and what you'd like to add!

Good luck, lovelies!

*A note from Coppertone: To be sure this product is right for you, always read and follow the label.