Sunscreen Protection Demistified


photo credit: wishymom (Stephanie Wallace Photography) via photopin cc
I have a teen that has skin as white as snow. Her goal for several summers is to get a ‘good tan’…. but knowing what I know, I can’t agree that there is such a thing. I have ran behind her, her whole life with creams and sprays trying to keep her from getting burned. But it seems every summer she gets one anyway. This year, in the spring, I told her that she would not be playing beach volleyball if she got any kind of burn….. so, she hid it from me. Turns out she couldn’t play anyway for other reasons so it sort of worked out.

She is spending time in Greece this summer…. without me. I’m not there to run after her and spray. It’s a big trip and I’m nervous about it. But I sent her off with lotions and sprays ranging from 30 to 60 SPF. I hope they are all empty by the time she gets back but somehow I bet that she will come back darker.

I had always been a little confused about sun screen (‘sun tan lotion’ in the ‘olden days’) and decided to visit a dermatologist to clear some things up and check on some moles. With sunscreen ranging from 15 to 110 SPF, how much protection are they really offering with those numbers? According to The New York Times, SPF 100 blocks out 99% of UVB rays, only 1% more than SPF 50. (SPF 30 is 96.7% effective) By the way, ‘SPF’ only indicates the protection against UVB rays, not UVA rays. So, read the label to look for ‘broad spectrum’ protection or ingredients like avobenzone or Mexoryl SX. They block out UVA rays.

Another thing to consider is the UV index from your weather channel. A UV Index of 5 and up requires your attention. Protection is necessary. Whether its the shade of a tree, an umbrella, a hat and clothes or sunscreen. There are 3 types of UV rays. A, B, and C. UVC is filtered by the ozone layer and does not reach the earth (for now). So, we’re good, considering its the most harmful. But UVB and UVA are nasty in their own right. Both contribute to skin damage, premature aging and skin cancer. UVB rays penetrate the outer layers of the skin and are the primary cause of sunburn. UVA rays penetrate more deeply into the skin, accelerate premature aging and wrinkles the most. They are prevalent in tanning salons where the devices can expose you to 5 times more UVA rays than natural sunlight. Depending on your surroundings, the UV rays can be increased by reflecting off of water, sand, snow and grass. The worst being fresh snow with almost 3 times the reflection ability of water for UVB rays.

One thing that surprised me was the frequency of reapplication necessary. Every 2-3 hours or more frequently if swimming. An adult will need about 2 tablespoons for proper coverage, applied 20 minutes before exposure. Using the proper amount is actually more important than choosing the SPF. If you use half of what you are supposed to, you will get the square root of the advertised SPF. So a 70 SPF will only give you 8.4 times protection. If you are in the sun for most of the day and using the right amount, you should finish an 88mL tube without a problem per adult. That’s going to cost more than parking…..!

Here is a rather shocking but fun video by Thomas Leveritt that shows sun damage to skin that you can’t see otherwise.