As a dermatologist, I often get asked about the “best moisturizer” or “number one facial product” that I recommend for women.  It’s pretty simple – sunscreen. Protecting your skin often and early is one the best things you can do to maintain your skin health in the long term.

Did you know that the way most people apply them, many sunscreens degrade in the sun within a few hours? It’s true! That’s why you will often hear that you should reapply often, especially if you are swimming, exercising, just sweating a lot.

There are two main types of solar radiation that reach the earth: UVA and UVB.  UVA is present at all times when the sun is out, from dawn ‘til dusk. It is responsible for causing wrinkles and sun-spots. It is also the main kind of radiation produced by tanning beds. UVB emission is highest from 10am – 2pm, and causes the majority of sunburns. It also contributes more to the mutations that lead to skin cancer.

“SPF” is the sun protection factor, which is a measurement of the amount of time you can spend in the sun with sunscreen on compared to without sunscreen. An SPF of 50, for example, means that you could theoretically stay outside 50 times longer with sunscreen on before you got burned. In practice this isn’t true, however, since most sunscreen ingredients degrade over time, and we often don’t apply enough. The SPF measures only a sunscreen’s protections against UVB rays, although most sunscreens contain ingredients to protect against UVA as well.

Use a sunscreen-containing product on your face every day, rain or shine. A lot of moisturizers and make up contain sunscreen now. When you know you are going to be out in the sun, use a waterproof sunscreen that is SPF 50 or greater, and try to re-apply after 2-3 hours if you are swimming or sweating a lot. Wear a wide-brimmed hat to further protect your face on really sunny days. And don’t visit tanning booths!

If you have noticed a new or changing spot on your skin, or you have a first degree relative (brother, sister, or parent) with melanoma, make an appointment with a dermatologist for a skin check. Melanoma affects young women as well as older people, and isn’t always in areas that have been exposed to the sun. Your dermatologist can examine and biopsy any suspicious moles. Early detection is life-saving! Check out http://www.skincancer.org/ for more information.