Sunscreens 101

You know sunscreen is your best defense when it comes to protecting your skin, but with the hundreds of varieties of sunscreens, including cream, liquid, powder, sprays and even towels – where do you even begin? Sunscreens now have new FDA mandated labels, making it clearer how long they are designed to protect your skin, whether they block against UVA and UVB rays and ingredient compositions.  Below is a simple introduction (or refresher) for what you will see on sunscreen labels and what should catch your eye.
Broad-Spectrum – This protects your skin from UVA and UVB rays.
  • UVA – Long-wave Rays – The dominant tanning ray, UVA rays penetrate the skin on a deeper level and cause cumulative damage over time leading to skin cancer and signs of aging. These rays also remove the ability of your white blood cells to attack malignant melanoma cells.
  •  UVB – Shortwave Rays – These rays are to blame for reddening and sunburn.  UVB rays contribute to photo damage and tanning, but they are a key player when it comes to skin cancer.
  •  UVC – Yes, there is a third form of rays the sun gives off! – This form of ray is absorbed by the Earth’s ozone layer and does not reach Earth.

Minimum SPF 30 – The FDA’s minimum recommendation is SPF 15, however the American Academy of Dermatology recommends at least an SPF 30 for optimal coverage. Studies show most of us are under-applying our sunscreen, leading to less protection. To get the SPF protection listed on the bottle, you need to use at least ONE OUNCE of sunscreen.  (Think one full shot glass of sunscreen to get your coverage.)

Now the real question you may be thinking: What is SPF and what’s with all the different numbers? SPF stands for Sun Protection Factor.  And the numbers that follow it indicate how long your skin is protected, when applied correctly.  If it takes about 20 minutes of sun exposure for your skin to start turning red, a sunscreen with an SPF 15 will protect your skin 15 times 20 (5 hours).  SPF 30 protects for 30 times 20, equaling 10 hours and so on.  REGARDLESS of your SPF, however, you still need to reapply your sunscreen at least every 40-80 minutes and when you get out of water. 

Inorganic / Organic Sunscreens –  Sunscreens can be broken into two categories, inorganic and organic.  Your inorganic sunscreens are those that have either Zinc Oxide or Titanium Dioxide, both mineral ingredients that sit on top of the skin and physically block the absorption of the sun’s rays. Organic sunscreens are absorbed by the skin and absorb damaging UV rays. There has been no real truth or evidence to support claims that certain organic sunscreens have unsafe ingredients and are harmful to the body. While there are debates over whether organic sunscreens, due to their absorption, may be more water and sweat resistant, there are many types of inorganic sunscreens which can be water resistant as well.  The important thing to remember is to find a sunscreen that satisfies the FDA requirements for being water / sweat resistant and use them according to the directions listed on the bottle.

One more note before we go:  Have you seen Skin Cancer / Skin Aging Alert listed in the Drug Facts section on your sunscreen bottle?  If so, this means the sunscreen will ONLY prevent sunburn and will NOT reduce the risk of skin cancer and early skin aging.  Stick with Broad-Spectrum and you’re covered for UVA and UVB rays.

Not sure you’ll be able to keep track of all of this?  Grab this great infographic guide to sunscreen from the American Academy of Dermatology! We have it readily available in our office and pass it out at community events as well.

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