Does SPF do any Good?

Posted on July 16, 2009 in Consumer Goods, Health & Medicine, The Environment

Sunscreens are rated on an SPF scale, meaning Sun Protection Factor. The higher the SPF, the longer you can stay in the sun without burning, theoretically. The number following SPF is commonly believed to mean the amount of time you can spend in the sun longer than you could without sunscreen.

For example, SPF 30 implies that you can remain outdoors in direct sun 30 times longer without burning than you could without it. This rule is very ambiguous and should not be taken for gospel, as everyone’s skin sensitivity is different. With the depletion of the ozone layer, dermatologists are recommending that everyone wear a minimum of SPF 15 every day, whether you are going to be in direct sun or not.

You should definitely increase the amount of SPF you are using if you plan on being on a plane, where the sun’s rays are even stronger. Persons visiting or residing in Australia should wear at least an SPF 30 daily, on all exposed body parts.

SPF works by reflecting, scattering, or absorbing excess UVA rays so that your skin does not take the full force of the sun. There are many compounds that are used to do this, the most popular being zinc oxide. SPF should be applied at least 10 minutes prior to sun exposure to be effective.