Summer may be over, but sunscreen needs to be worn all year long on key areas like your face, neck, and backs of your hands. What is the best sunscreen? Catchwords like "dry," "sheer," "broadband," and inflated SPF ratings can make shopping for sunscreen dizzying. This post gets down to the knitty gritty essentials of sunscreen to help you sift through all the marketing and find a sunscreen that work's best for you. Read more for the pros and cons.
The Skinny Science:
Sunscreen addresses two bands of ultra-violet light: UVA (400-315 nm) and UVB (315-280 nm). The sun produces a third band of ultra-violet light, UVC (280-100 nm), but this is largely blocked by ozone. The SPF rating on sunscreen bottles measure protection against UVB (the kind responsible for sunburns). Unfortunately, it's UVA that is the primary cause for the ugly stuff like skin cancer and premature skin aging. Currently, the FDA has no rating system to measure UVA protection.
There are two types of sunscreens: (1) physical sunscreens and (2) chemical sunscreens. Physical sunscreens, also called mineral sunscreens, form an opaque layer that sits on your skins surface, reflecting or scattering UVA/UVB before it penetrates your skin. There are two types of physical sunscreens available: zinc oxide and titanium dioxide. In contrast, chemical sunscreens absorb into your skin, where it absorbs UVA/UVB. Chemical sunscreens available in the U.S. include: avobenzone (a.k.a. Parsol 1789), oxybenzone, and ecamsule (a.k.a. mexoryl).
Word to the Wise:
How do you know if you want a physical sunscreen or a chemical one? Among all the choices, one thing is clear: you want protection against both UVA and UVB rays. Here's a quick list of pros and cons to help you decide.
Physical/Mineral Sunscreen: (zinc oxide, titanium dioxide)
• Extremely stable and long-lasting protection.
• Remains on the surface. Doesn't penetrate skin.
• New formulations blend better, but may have subtly whitish appearance without
• Bad when minerals are micronized or nano-sized. Solved by avoiding
ingredients listed as "micronized" or less than 100nm (nm =nanometers).
Chemical Sunscreen: (avobenzone a.k.a. Parsol 1789, oxybenzone, ecamsule a.k.a. mexoryl)
• Has sheer apearance.
• Mexoryl SX (ecamsule) is argued as the best in stability but is sold in the U.S. in
very limited products.
• Oxybenzone is a suspected hormone disruptor. Best to avoid it altogether,
especially for children.
• Has inferior stability. Degrades rapidly without adequate stabilizing chemicals,
leaving you unprotected.
• Absorbs into skin.
Green Your Routine — the Verdict:
After reviewing the data, the Environmental Working Group's verdict is that physical/mineral sunscreens are the better choice over chemical ones because they are safer and perform better. In other words, they don't penetrate your skin, and they provide stable longer-lasting protection. For EWG's picks, go to Best Sunscreens of 2010.
The Bottom Line on Sunscreen:
Despite this verdict, there is currently no ideal sunscreen, and as the Mayo Clinic advises, the best strategy on sun protection is a combination of shade, clothing, sunscreen and common sense.
As always, stay informed, be conscious of cumulative exposure, and green your routine to what fits you best.
• Alternative names quicklist: Physical sunscreens (zinc oxide, titanium dioxide).
Chemical sunscreens (avobenzone a.k.a. Parsol 1789, ecamsule a.k.a.
• Best to avoid oxybenzone.
• Vitamin D deficiency is quickly gaining speed as a serious matter. Sunscreen blocks
UVB which the body needs for vitamin D production. Doctors are recommending 15
minutes of unprotected sun exposure daily.
• For more information, check out these sources: Mayo Clinic, Environmental Working
Group's Sunscreen Guide.
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• Flame Retardants Under Fire: What Are PBDEs and BFRs?
• Breast Defense: Chemicals and the Environment
• What is BPA, a.k.a. Bisphenol A?
• The Secret Chemicals in Fragrances
• Hygiene Products for Dummies: Cosmetic Safety Database
• What is Dioxin? How to Avoid Toxin Dioxin
• The Dirt on Bleach: What makes Chlorine Bleach Bad News?
• What is Triclosan? A Shady Chemical You should Unfriend
10 Ingredients To Avoid In Your Face Products
(Image: Flickr member Luca Castellazzi licensed for use under Creative Commons)