We all know that one plus one equals two. In the same way, sun exposure plus unprotected skin equals skin cancer. More than 1 million cases of skin cancer are diagnosed annually.

But by being smart about the sun, and protecting yourself and your family, you can help reduce that number. Test your sun IQ by answering the following questions about sun exposure.

1. Darker skin (either natural or from a tan) is protected from the sun.
         
   False. Darker skin is just as susceptible to skin cancer as lighter skin. And tanning indicates a change in your skin, so no tan is healthy or safe. Everyone should use a broad-spectrum sunscreen that blocks both UVA and UVB rays with an SPF of at least 15 (30 or higher if you have a history of skin cancer). Apply sunscreen about an hour before going out into the sun, and reapply every two hours (more often if you are swimming).
        
2. Wearing white-colored clothing protects you from the sun.
         
   False. It’s actually not the color of the clothing, but the thickness of the material that creates sun protection. So a thin white T-shirt would offer less sun protection than a thick and tightly woven white knit shirt. Other recommended items include sunglasses and a hat (which can actually provide an SPF of more than 30).
           
3. The only time you need to wear sunscreen is when you plan to be outdoors for an extended period of time.
          
   False. It’s actually best to wear sunscreen every day. You should routinely use sunscreen if you will be exposed to the sun for more than 10 to 15 minutes. Believe it or not, your daily drive to work and sitting in your office next to your open window provide enough accumulated sun exposure to damage your skin. Also remember that sunscreen is still important in the winter or during cloudy days because UVA/UVB rays are still being absorbed by your skin.
         
4. Sun exposure ensures I get adequate levels of Vitamin D.
            
   True. But you only need about 5 to 15 minutes of sun exposure two to three times a week on your face and hands for your body to produce a sufficient supply of Vitamin D. In addition, milk and other Vitamin D-rich foods as well as multivitamins are excellent sources of Vitamin D.
         
5. If I wear sunscreen and a hat or protective clothing, then it’s OK for me to stay outdoors all day long.
        
   False. Sunscreen and other items are only protective measures. Staying out of the sun is the best way to prevent skin cancer. The sun’s rays are strongest between 10 a.m. and 3 p.m., so it’s highly recommended that you stay out of the sun during those hours.
          
6. A tanning bed gives you a safe tan.
         
   False. Tanning beds use ultraviolet light, similar to the UVA and UVB rays emitted by the sun. In fact, the effects of UV exposure are intensified in a tanning bed. Spending an hour in a tanning bed is easily equivalent to spending several hours outside in the sun.
        
7. Spots and roughness are a natural part of aging, and there’s nothing I can do to prevent that.
   
   False. Sun exposure accelerates aging. Compare skin on your face and hands with skin on a part of your body that is not regularly exposed to the sun and see the difference. All skin types should also remember to watch for new dark spots or changes in spots on the skin, and especially on palms, soles or around nails. These could be signs of skin cancer and should be checked out by a physician.

If you answered all seven correctly, congratulations! And if you missed some answers, don’t worry. The most important test of your sun smarts actually comes now. By practicing good habits-wearing sunscreen, staying indoors during peak sun hours and wearing protective clothing-you can score big by protecting your skin and helping to prevent skin cancer.