Health Media Today
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Sun Safety: Understanding Sunscreen and SPF
Author : Carolyn Eagle, Senior Editor, Health Media Today Category : Health and Wellness
With the staggering choice of sunscreens available today, choosing which one is good for yourself and your family can be a daunting task. Each brand has its own special formulation that makes different claims for what it can do for your skin but when it comes right down to it, there is only one important factor to any sunscreen and that’s its SPF number.
With some sunscreens boasting an SPF as high at 70, it’s easy to have a false sense of security. After all, a 70 SPF must mean you can slather it on and stay out in the sun worry-free all day, right? Not quite. And here’s why.
WHAT IS SUNSCREEN PROTECTING YOU FROM?
The sun emits UVA and UVB rays. UVA rays are the ones that cause the long-term skin damage and penetrate more deeply. UVB rays are the ones that cause you to burn and redden. You need to make sure a sunscreen provides protection against both, which is usually indicated by the term “Broad Spectrum” on the label.
WHAT DOES SPF MEAN?
Simply, SPF stands for Sun Protection Factor. It is, in theory, the amount of time you can stay in the sun without getting sunburned with sunscreen as opposed to without. The simple formula is this: SPF x Minutes to burn without sunscreen = Maximum amount of time you are protected with that sunscreen
So, if think you will burn after 10 minutes and you have a sunscreen with a 15 SPF you would calculate 10 x 15 = 150 minutes of protection
SO A REALLY HIGH SPF MUST MEAN I’M COVERED ALL DAY?
Absolutely not. This is the important thing to know about how to manage how much sunscreen SPF you need and when you need to reapply
• Most people only apply about half of the amount that was used in laboratory testing
• Certain medications can increase your sensitivity to sun so make sure you know if anything you are taking has these side effects and adjust your SPF accordingly
• For maximum effectiveness, sunscreen should be applied 15 to 30 minutes before sun exposure to allow it to absorb into skin
• Even waterproof and sweat proof sunscreens decrease in effectiveness when we swim or sweat
• Sand wears off sunscreen. As you frolic in the waves, remember the sandy bottom is wearing off your sunscreen
• Sunscreen sprays have come under scrutiny because it is difficult to get enough coverage of the product onto the skin to be properly effective. There is also investigation into the harm of inhaling spray sunscreens.
• The ability of sunscreen to absorb harmful UVB rays does not increase exponentially as SPF numbers go up. Simply put, an SPF of 15 absorbs 93.3% of UVB rays but an SPF of 50 absorbs 98%. Not much difference even though the SPF number has jumped from 15 to 50. The American FDA actually recommended that sunscreen SPF claims be capped at a level of 30 in order to avoid confusion or a false sense of security, but companies have ignored these recommendations.