skip to Main Content

The One Mistake That is Aging You and Could Lead to Skin Cancer

Dr._Forney_Small2_350_300_c1_c__1“I read that there is no reason to use more than a SPF 30.”  “I heard that spf 15 and spf 30 are virtually the same.”  Variations of these comments come my way daily especially now as I preach sun protection for the summer. Yes, there is a study, which shows that WHEN APPLIED IN A CONTROLLED SETTING, there is very little difference between a SPF 15 and a SPF 30. What is a controlled setting?  Paid attendants apply 2 milligrams of sunscreen to every square centimeter of exposed skin every 80 minutes.  For the average adult, that is over an ounce of sunscreen every hour and a half.  Most sunscreen bottle holds 8 ounces. So, if you are at the beach from 10 to 4, you alone should use a half bottle of sunscreen per day!  A family of 4 would use almost 2 bottles in a day.  That is 12 bottles for a week’s vacation. Studies show that most people apply between ¼ and ½ the recommended amount of sunscreen, which means a SPF 15 is really somewhere between a SPF 4 and SPF 8, a SPF 30 between an 8 and a 15.  Few remember to reapply every 80 minutes and the longer between applications, the more the protection decreases, so that SPF 30 applied at 25% coverage is about a 4 after 3 hours. SPF 70-100 doesn’t cost much more than a 15 or a 30, but if you apply it as most do, it does quadruple your protection. So, do your skin a favor. Grab the highest number, apply a lot, and reapply every hour and a half. Even better, wear a SPF 50 swim shirt or rash guard and just use sunscreen on your hand, neck, face, ears and legs/feet.  It is very cost effective.  Enjoy.