By Daniel I. Wasserman, M.D.
May is Skin Cancer Awareness Month which is an excellent opportunity to not only raise awareness for the types, frequency, and treatment of skin cancer, but also the first line of defense: sunscreen. Nearly all patients visit dentists despite flossing and brushing their teeth, but as we have all been informed by our dental hygienists: we can do a better job. Sunscreen suffers from the same circumstances of inadequacy. Many people in Florida believe that putting on a sunscreen in the morning is adequate, but that is only the beginning. To start the conversation, we will discuss the three Q’s of sunscreen: Quality, Quantity, and freQuency.
Quality refers to several specifications regarding the specific sunscreen you are using. The most common question patients will have is regarding SPF. SPF refers to Sun Protection Factor. An easy cheat code to understand what SPF stands for is to simply inverse the number. This will represent how much is getting through the sunscreen and causing damage to your skin. For instance, an SPF of 30 can be thought of 1/30th of the sun is getting through. 1/50th is equal to about 2% and 1/100th is equal to about 1%, so one can see that increasing the SPF beyond 40 or 50 provides very little additional protection. Another important consideration is the labelling of the sunscreen as Broad-Spectrum. This refers to the sunscreen’s ability to protect against both UVA and UVB. SPF refers only to a product’s ability to protect against UVB. Most broad-spectrum sunscreens contain either zinc oxide or titanium dioxide or both. Everyone should be looking for sunscreens that contain one or both of these ingredients to provide them with the most comprehensive protection against UV radiation.
Quantity refers to the amount of product one applies to their own skin. Studies have demonstrated that the average amount of sunscreen a manufacturer applies per square inch when testing for a SPF score is about 4 times more than the average person applies per square inch. This suggests that the public is horribly underapplying enough sunscreen for reliable protection. I inform patients not to apply four times more sunscreen, but if one could simply double the amount then that should provide a substantial improvement in protection.
FreQuency refers to how often one applies sunscreen. It is important to understand that as sunscreen is absorbing or chemically interacting with UV radiation, it is in fact losing its potency. It is therefore imperative that individuals reapply sunscreen throughout their activity in the sun. An easy thought that I provide patients with is: Front 9/Back 9. Apply before the front 9 on the golf course and then again for the back 9. This can equate to about every 1.5-2 hours. If one is at the beach, playing tennis or golf, or on the boat, a good rule of thumb is to reapply every 1.5-2 hours.
In summary, it is important to remember that if you are still developing a tan, then your sun protection is inadequate. A tan is representative of sick skin, analogous to a smoker’s cough. If you are applying sunscreen and still have a tan, then think of some of the methods described above to hopefully help your skin improve its overall health.
Daniel I. Wasserman, MD
Fellowship-trained Laser and Cosmetic Dermatologist Fellowship-trained Mohs Surgeon Board Certified Dermatologist
Dr. Wasserman is a board certified dermatologist with fellowship training at Harvard Medical School in laser and cosmetic surgery, as well as fellowship training in Mohs skin cancer surgery. He has contributed as a dermatology expert for online and print magazines. In addition, he frequently lectures to professional societies and organizations on his diverse research. For more information about skin care visit the Skin Wellness Physicians website at www.skinwellnessflorida.com
Skin Wellness Physicians