On June 14th of 2011, I wrote this post and referred to another I had written in 2009 - both were about the changes in how sunscreen products in the United States could be labeled. Alas, the day has arrived (or will next month) - and most of what I told you in those past posts is now law.  There is one great exception - one great, unfortunate exception which speaks to the power of industry and the discretion of the FDA.  [this is of special concern to me because the same thing is happening with the law that mandates nutrition disclosures at restaurants... the law was passed years ago, and the FDA has the responsibility and the authority for the final rule but industry is pushing back hard... yet, so are scientists, so maybe this time the changes will be in our favor - she said in a major side bar]

The unfortunate label change no go for sunscreen is the ban on claiming SPF - sun factor protection - greater than 50.

First let me tell you what did survive from the original law:
No company can advertise its sunscreen as waterproof (sweat proof, or call itself a sun block).
I thought that all sunscreens would have to provide UV A (the kind most associated with cancer) and UV B (associated with burning) protection, but I just double checked the FDA website and now I am as confused as ever by their final rule (I am also losing faith in this government agency).

Anyway, instead of everyone having to provide both forms of protection, only those that do can call themselves Broad Spectrum.  Bottom line:if the product says Broad Spectrum and is SPF 15 or higher - that is the one you want to buy.

Broad Spectrum sunscreen protects against both types of UV Rays.

Mass confusion continues over what SPF actually means.  I will do my best to explain it in a moment, but science tells us that for a product to offer adequate protection the values should be between 15 and 50, but 30 is likely sufficient.  There is no evidence to support that SPF over 50 makes a difference, makes a clinically important difference, but the industry of sunscreen makers is still fighting to use the higher numbers.

As I understand it, the amount of time that a person can be in the sunlight, unprotected without beginning to burn is quite individualized.  It depends on the time of year, where you are physically located and your skin's pigment (fair or olive, e.g.).  It does not have anything to do with whether or not you have a 'base tan!'

SPF is related to the time it takes you to burn.  So whatever that time is, say I start to burn after 30 minutes because of my olive skin - if I use SPF 15, 15 x 30 = 450 or just over 7 hours.  I could be in the sun for over 7 hours wearing SPF 15 with reasonable assurance of not being burned (UVB protection) and as long as I have on Broad Spectrum SPF 15 - I should also be protected from the UVA rays during that time.

If I chose a 30 SPF, then I could stay in the sun longer (30 x 30) without beginning to burn.  
If I were a fairer skinned person, I might begin to burn in 15 minutes, and the math would be different.  SPF 15, 15 x 15 = 225 minutes so almost 4 hours;  SPF 30, 30 x 15 = as above.

Key to this protection is that the lotion be applied thoroughly and in a sufficient amount.  Any time one sweats, goes in the water and/or towels off, the lotion needs to be reapplied. Therefore, the labels advise that you reapply every two hours.

Sunscreens that are sprayed on may not be as effective.  The research is still pending (due to the body coverage issue) and there may be concern about breathing the fumes from the spray.

It is also important to limit your time in the sun, regardless of protection - 7 hours in full sun would be dangerous.  The best protection comes form hats, glasses, clothes and shade. 

 Of course, some time in the sun is necessary for Vitamin D production  - YAY!

Once again I link you to the Skin Cancer Foundation for more information.  I am sending you to the page with a sun safety quiz!  You better get a 100!