How smart are you when it comes to SPF and skin protection?  Take this quiz to find out!

1.  I can use sunscreen I bought last year.                                                            TRUE  or  FALSE

2.  Only the sun’s UVA rays are harmful.                                                               TRUE  or  FALSE

3.  A sunscreen with an SPF of 30 has twice as much sun protection as one with SPF of 15..      

                                                                                                                                   TRUE  or  FALSE

4.  Using sunscreen will limit the amount of Vitamin D I get.                               TRUE  or  FALSE

5.  The SPF tells me how well a sunscreen protects against UVA and UVB rays.  

                                                                                                                                   TRUE   or  FALSE

ANSWERS

1. TRUE.  The Food and Drug Administration (FDA) requires that all sunscreens be stable and at their original strength for at least three years, unless there is an expiration date on the container.  However, if you are using the appropriate amount, a bottle of sunscreen should not last very long.  You should use one ounce of sunscreen, enough to fill a shot glass, to cover the exposed areas of the body properly.

2. FALSE.  Sunlight has two types of harmful rays — ultraviolet A (UVA) rays and ultraviolet B (UVB) rays. UVA rays can cause suppression of the immune system, which interferes with the immune system's ability to protect you against the development and spread of skin cancer. The UVB rays are the sun's burning rays and are the primary cause of sunburn. Excessive exposure to both forms of UV rays can lead to the development of skin cancer.  The United States Department of Health & Human Services has declared ultraviolet (UV) radiation from the sun and artificial sources, such as tanning beds and sun lamps, as a known carcinogen (cancer-causing substance).

3. FALSE.  UVB protection does not increase proportionately with a designated SPF number. For example, an SPF of 30 screens 97 percent of UVB rays, while an SPF of 15 screens 93 percent of UVB rays and an SPF of 2 screens 50 percent of UVB rays. However, inadequate application of sunscreen may result in a lower SPF than the product contains.

4. TRUE.  Since sun exposure is responsible for vitamin D production in the skin, wearing sunscreen will decrease your skin's production of vitamin D. If you wear sunscreen and are concerned that are not getting enough vitamin D, discuss your options for obtaining sufficient vitamin D from foods and/or vitamin supplements with your doctor.

5. FALSE.  A sunscreen’s SPF number only reflects the product's screening ability for UVB rays. At present, there is no FDA-approved rating system that identifies UVA protection. Scientists are working to create a standardized testing system to measure UVA protection.

Information adapted from the American Academy of Dermatology website.

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