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Sun Protection – What you need to know:

Now that summer is here, it is extra important to use sunscreen to protect yourself from the sun. Diligent use of sunscreen can help prevent premature aging of your skin as well as skin cancer. Sunscreen should be used every day if you are going to be in the sun for more than 20 minutes.

Why is the sunlight damaging to my skin?

You may not feel like the sun is harming your skin, but by the time you realize it the damage has likely already been done. Sunlight consists of two types of harmful rays — UVA rays and UVB rays. The UVB rays are the sun´s burning rays (which are usually blocked by window glass) and are the primary cause of sunburn and skin cancer. UVA rays (which pass through window glass) penetrate deeper into the skin and can also contribute to sunburns and skin cancer. Both UVA and UVB rays can cause suppression of the immune system which helps to protect you against the development and spread of skin cancer.

Which SPF sunscreen is best?

SPF stands for Sun Protection Factor. Sunscreens are rated or classified by the strength of their SPF. In general, having a sunscreen with SPF greater than 30 is what is recommended. The SPF numbers on the packaging can range from as low as 2 to greater than 70. These numbers refer to the product’s ability to deflect the sun´s burning rays. The sunscreen SPF rating is calculated by comparing the amount of time needed to produce a sunburn on sunscreen protected skin to the amount of time needed to cause a sunburn on unprotected skin. For example, if a sunscreen is rated SPF 5 and a fair-skinned person who would normally turn red after ten minutes of exposure in the sun uses it, it would take fifty minutes of exposure for the skin to turn red. A sunscreen with an SPF of 15 would allow that person to multiply that initial burning time by 15, which means it would take 15 times longer to burn, or 150 minutes.

SPF protection does not actually increase proportionately with a designated SPF number. In higher SPFs, such as an SPF of 30, 97 percent of sunburning rays are deflected, while an SPF of 15 indicates 93 percent deflection and an SPF of 2 equals 50 percent deflection.

When and how often should I apply sunscreen?

Any time that you are outside and your skin is exposed, you should be wearing sunscreen. Even on a cloudy day, 80 percent of the sun’s ultraviolet rays pass through the clouds. Sunscreens should be applied to dry skin 15-30 minutes before going outdoors. When applying sunscreen, pay particular attention to the face, ears, hands and arms. Be careful to cover exposed areas completely so you don’t get a patchy sunburn in the areas that you missed. Don’t forget that lips get sunburned too, so apply a lip balm that contains sunscreen, preferably with an SPF of 15 or higher. Sunscreen can also be applied underneath makeup if your makeup doesn’t already have it. Sunscreens should be re-applied on average every two hours or sooner depending on your skin type. You should also re-apply after swimming or perspiring heavily (even if the sunscreen says it is water resistant). Sunscreens rub off as well as wash off, so if you’ve towel-dried, reapply sunscreen for continued protection.

Here are some tips about how to keep you safe from the sun’s harmful rays:


Please call our office at 305-27907677 to make your appointment for your annual skin check. Same day appointments are available. We look forward to taking care of you!

David A. Ross, MD Sports Medicine Physician

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As you are all aware, we as a world and a nation are in the midst of a pandemic caused by the COVID-19 coronavirus. This virus, affecting the entire country with more than 3000 cases to date, has now reached our immediate community of Miami-Dade County.