Sunscreen Basics

Photo by: Wallpaperbase.com

With summer in full swing, it’s important to understand the basics of sunscreen. 

UVA vs. UVB Rays

Sunlight consists of two harmful rays- UVA and UVB rays.  The UVB rays are the sun’s burning rays and are the primary cause of sunburn and skin cancer.  UVA rays are invisible, can penetrate deeper into the skin and can cause premature aging and wrinkling of the skin.  A sunscreen that offers “broad-spectrum” will protect you from the radiation of both UVA and UVB rays.

SPF

The sun protection factor (SPF) refers to the product’s ability to screen or block out the sun’s harmful rays.  For example, if you use a sunscreen with an SPF 15, you can stay in the sun 15 times longer than without sunscreen before you will burn.  As the SPF increases proportionally by the number, the strength of the sunscreen does not.  An SPF 2 will deflect 50% of the ultraviolet radiation.  An SPF 15 will deflect 93% and an SPF 30 will deflect 97%.

When and how much should be applied?

Sunscreen should be applied to dry skin 15-30 minutes before going outdoors.  One ounce, enough to fill a shot glass, is the recommended amount needed to cover the exposed areas of the body properly.  Sunscreen should be reapplied every 2 hours or after swimming or heavy perspiration.  Even water-resistant sunscreen loses its effectiveness after 80 minutes in the water.

Ingredients to look for in sunscreen

Ingredients that provide broad-spectrum protection include benzophenones (oxybenzone), cinnamates (octylmethyl cinnamate and cinoxate), sulisobenzone, titanium dioxide, zinc oxide and avobenzone (parsol 1789).

Sources: www.vashonorganics.com, and the American Melanoma Foundation