One of the most confusing things about sunscreen is “UVA-versus-UVB.” Sunlight consists of two types of harmful rays that reach the earth: ultraviolet A (UVA) rays and ultraviolet B (UVB) rays. Overexposure to either can lead to skin cancer, which is why you need to wear “broad-spectrum” sunscreen, which protects you from both, and reapply it often. The two types of rays are responsible for different, yet equally sinister skin-damaging things.
UVA Rays: Cause Aging
These can prematurely age your skin (think A equals aging), leading to wrinkles and age spots. These are also the sneaky ones that can pass through window glass.
UVB Rays: Cause Burns
These are the primary cause of sunburn and are blocked by window glass, which is why you don’t get burned while driving. UVB rays also stimulate melanocyte cells to produce more melanin, which shows up as a burn, tan, freckle, brown or age spot, or hyperpigmentation.
Looking at the SPF number is important, but keep in mind that SPF is mainly a measure of UVB rays and does not measure UVA absorption in to the skin. Make sure the sunscreen you choose displays the “broad-spectrum” label on it to ensure full protection. Here are a few of our favorite picks:
Neutrogena Ultra Sheer Dry-Touch Sunblock SPF 70, drugstore.com, $10
La Roche-Posay Anthelios Ultra Light Sunscreen SPF 45, dermstore.com, $24
Shiseido Urban Environment Oil-Free UV Protector SPF 42, nordstrom.com, $29
