Ultraviolet Rays - What's The Difference Between UVA and UVB

© Michelle Howard Smith - All Rights Reserved

Many people do not know much about ultraviolet rays or the true difference between UVA and UVB rays. Most people know they are ultraviolet rays that come from the sun and that you should use sunblock but that's about the extent of their knowledge.  It's important to know the difference between UVA and UVB rays because of their potentially damaging effects.

First off, UV stands for ultraviolet radiation.  UVA and UVB rays have different wavelengths and damage the skin in different ways.

UVA rays penetrate the skin deeper than UVB rays and cause premature wrinkles and skin cancer.  UVA rays are also responsible for sun tanning which is really the result of your pigment darkening to protect your skin from damage.  Repeated tanning can cause skin cancer. (Who wants a suntan now?)

UVB rays can also damage your skin and are responsible for causing sunburn.

Use a Broad Spectrum Sunblock for Ultraviolet Rays

The US Food and Drug Administration has given us a list of the ingredients that make a sunblock effective for both types of ultraviolet rays:

Protection from UVA Rays:

    * Avobenzone
    * Ecamsule (Mexoryl SX)
    * Mexoryl XL
    * Oxybenzone and Dyoxybenzone (both also protect against UVB Rays)
    * Titanium dioxide and Micronized zinc oxide (both also protect against UVB Rays)

Protection from UVB Rays:

    * P-aminobenzoic acid (PABA)
   * Octinoxate
    * Ensulizole acid
    * Padimate O
    * Trolamine Salycilate

For full protection, the sunblock ingredients need to protect in wavelengths (UVA and UVB) from 290 to 400 nm (wavelength protection).  However, just because you get a sunblock or sunscreen that has the recommended wave length coverage doesn't me you can sit out in the sun baking for hours.  Nothing is 100% effective so use wisdom and protect your skin.