SUMMER IS HERE! We, at the Julian Institute of Plastic Surgery, get asked frequently about sun protection. We also unfortunately see and treat the negative effects of sun exposure. These include skin cancer (Basal cell carcinoma, Squamous cell carcinoma and Melanoma), but also wrinkles and sagging of the skin due to collagen degradation. Sun light exposes us to ultraviolet (UV) radiation in the form of UVA and UVB rays. UVB is what causes a sunburn and leads to many skin cancers. UVA actually penetrates deeper into the skin and is also responsible for skin cancer but also wrinkles and saggy skin.
Many sunscreens only provide protection to UVB and the SPF (sun protection factor) rating mainly refers to the amount of UVB protection alone. The SPF rating can also be somewhat misleading. For example, SPF of 15 blocks 93% of the UVB radiation, SPF of 30 blocks 97% and SPF of 50 blocks 98%. So a higher SPF does block more UVB rays but once you get above 30-50 the benefits are negligible. Well, what about the UVA rays? A good sunscreen should also provide protection against UVA radiation. This should be clearly stated on the label.
The active ingredients of the sunscreen are also very important. Sunscreens can be categorized as either chemical or physical blockers. Chemical sunscreens absorb, filter or breakdown UV rays whereas the physical blockers literally block the rays from entering the skin. The chemical blockers typically need to be re-applied more often but go on smoother, do not feel as thick and do not leave a whitish appearance. The physical blockers can be pasty but do provide longer protection to both UVA and UVB rays. The most common physical blockers are zinc oxide and titanium dioxide. Of the two, zinc oxide blocks the entire spectrum of UVA and UVB whereas titanium dioxide is not quite as good at blocking the full spectrum of UVA rays.
What about the spray on sunscreens? These can be convenient because they are quick and don’t require getting your hands slimy. But therein lies the problem. Many people do not spray on enough to get uniform coverage. And for the best coverage and skin penetration, rubbing the spray on sunscreen should be done but that defeats their purpose. There is also concern about inhaling the sunscreens while applying them and the health issues that may result.
Choose a good quality sunscreen in the 30-50 SPF range that covers both UVA and UVB rays. I prefer the physical blocking agents, specifically zinc oxide or titanium dioxide combined with another UVA protector as the main ingredient. The chosen sunscreen should be reapplied every 2 hours and after sweating or swimming. Apply the sunscreen in an even and complete layer before going outside rather than after walking to the beach or golf course. Many make this mistake and sun damage now has already occurred! And don’t forget to apply sunscreen to your ears, lips and scalp if you have thinning hair!
Have a great and sun-safe summer!
-Dr. Marc Polecritti