Are you Sunscreen Savvy?

Understanding Sunshine

When you go out into the sun you are being exposed to two types of rays:

UVA: penetrates deep into our skin but doesn’t cause sunburn. UVA rays are the same strength year round and it’s difficult to get full protection from these rays. It’s also much harder to measure since there are no visible effects from UVA rays.  

UVB: are the rays that turn our skin red. They don’t penetrate as deeply but affect the top layers of skin. These are effectively blocked with sunscreen.

Both UVA and UVB rays cause damage to the skin’s collagen as well as change the DNA, which can result in skin cancer. UVB damages skin at a much slower rate than UVA.

Know your sunscreen

Sun protection from a bottle comes in two forms:

Sunscreens: are chemicals that absorb the radiation as it hits our skin. Broad spectrum sunscreens offer protection about both UVA and UVB although UVA protection is limited.

Sunblock: physically block both kinds of UV rays by reflecting them away from the skin. The most popular are zinc oxide (ZO) or titanium dioxide (TiO2.

Both types are called sunscreen so you have to read the labels carefully.

Understand SPF

Sun Protection Factor (SPF) focuses on the UVB rays and never UVA – since this is impossible to accurately measure. Most of us have been using the SPF factor incorrectly.

The classic formula of taking the SPF and multiplying by ten to give you how many minutes of protection doesn’t work. That’s because according to the FDA, SPF actually measures the amount to sun exposure and not the protection time. It’s impossible to accurately measure how many minutes of protection is being offered since there are so many variables including the strength of the sun, time of day and a person’s skin.

Use SPF to determine how much UVB is blocked:

• 2 SPF blocks 50 percent
• 10 SPF blocks 90 percent
• 15 SPF blocks 93 percent
• 30 SPF blocks 96.67 percent
• 50 SPF blocks 98 percent

Buyer Beware

Sunscreens make a lot of claims that are not exactly accurate. According to testing done by the EWG (Environmental Working Group) no sunscreen offers full UVA protection despite claims of being “broad spectrum.”  Since there are no official ratings for UVA protections, most are listed vaguely as low, medium or high. 

EWG  also cautions that no sunscreen is chemical-free, water-proof and or can offer “all-day protection.” Whatever the brand, most sunscreens give between 60 to 90 minutes of protection so they need to be re-applied at regular intervals. All sunscreens have to use some kind of chemical in order to work.

Find out how effective your sunscreen is and what ingredients it contains at the EWG sunscreen database.

Don't Be Cheap

The single biggest mistake people make when applying sunscreen is not putting on enough. You need at least a capful (about a teaspoon) for each limb. That means a 100ml tube should last you for three full applications.

The best advice? “Get it right first off and put the right amount on. Apply the product, then apply it all over again. In two hours, reapply,” says Gavin Greenoak of the Australian Photobiology Testing Facility.

The most common areas forgotten or missed: neck, ears, nose, chest,hands,feet, back of legs.

Past Due Date

Your sunscreen will last two years only if it was stored below 25˚C. If you left it in the glove box all summer or let it bake in the sun then it’s probably a good idea to replace it with a fresher batch. Heat does strange things to the chemical compounds, rendering them ineffective.

The Best Protection 

Prevention is the best sunscreen of all. If you are fair-skinned, head for shade between 11 am and 3 pm when the sun is the most intense. Cover up with a hat or shirt to prevent burning. Use common sense—no sunscreen is going to protect you from burning if you are lying outside for hours under the scorching sun.

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