Dear OncoLink "Ask The Experts,"
Is there a specific ingredient to look for in sunscreen that makes it better?
Christopher J. Miller, MD, Assistant Professor of Dermatology at the Abramson Cancer Center of the University of Pennsylvania, responds:
There are currently 17 FDA approved ingredients for sunscreen in the United States. Some ingredients block more ultraviolet rays than others. As a rule, you should look for sunscreens with a bottle that says "UVA and UVB protection." The SPF on the bottle refers to your protection from UVB rays, the ones that cause skin cancer. Currently, there is no standard to tell you how well the sunscreen protects you from UVA rays, which are known to cause skin cancer and accelerate the aging of your skin. Since there is no standard for you to judge UVA protection, you should look for ingredients that specifically protect you. Since only a few of the 17 FDA approved sunscreen ingredients provide good UVA protection, there aren't too many to remember. Look for sunscreens with zinc oxide, titanium dioxide, or mexoryl. Avobenzone also provides UVA protection, but sun exposure destabilizes avobenzone, so its protective effects don't last long after exposure to the sun.
This question and answer was part of the OncoLink Brown Bag Chat Series: Sun Safety and Skin Cancer Prevention Webchat. View the entire transcript here.