Another way to look at this question is: how dangerous is reflected UV light?
It’s tempting to believe that shade totally protects your skin, but think about it for a minute. We know that light rays bounce off things just like balls do. When UV rays hit pavement they bounce upwards. When UV rays hit a sunny wall they bounce off too – yes – potentially into the shade. If that shade is created by your hat, then the rays hit your skin.
So … the bottom line is that if the sun is up and you are outdoors, your skin will get some UV ray exposure. This reflected exposure will be greater if you are at the edge of the shade, near the sunny area. Also, if you are on the water or near a highly reflective surface, you will get more UV exposure.
To give you a real life example of how reflection intensifies UV exposure, the worst sunburn I ever had as a kid came from skiing at Squaw Valley in the spring on a sunny day. The rays were bouncing off the snow, so I was getting them from both above and below. I burnt so badly that the whites of my eyes burnt too. Another example, to clarify the risk of exposure even when you wear a hat, is the time I got a lovely sunburn wearing a broad brim hat on a spring day while sailing on a white sailboat in the San Francisco Bay. UV rays were bouncing off of the water and the boat. Those were the days when mineral sunscreens were not widely available and I was wearing a chemical avobenzone product. I reapplied it, but the exposure was too great for the chemicals (which breakdown when light is blocked) and my fair skin burnt badly. I’m sad about both of those mistakes. Most of us have stories like that. What are yours?
I like to recommend a logical multi-level strategy to protect your skin from the sun. Expect that UV rays bouncing off reflective surfaces will be worse in the direct sun; they will still be pretty intense when you are on the edge of the shade and they will be less intense when you are deeper into the shade. That’s because, as you can probably imagine, the bouncing UV rays are more likely to have hit something (or someone) on the periphery of the shade and never reach you when you are in the deep shade. It’s why, when you select a table at an outdoor cafe (a lovely fantasy in the dead of winter, isn’t it!) be sure to ask for one well under the shade, not right on the edge. Likewise, when you pick a sun hat, the broader the brim the better.
Do you think that the softer morning and evening sun is gentle and safe?
Tempted to skip the hat in early morning or late afternoon? Can you skip the sunscreen then?
No, on both. I’m sorry but those rays do harm your skin too. They are UVA which is very damaging. UVA burns less but still is very potent at causing wrinkles, pigment problems, and skin cancer. Also, the sun hits your skin tangentially when it is low in the sky and sneaks under your perfect wide brim sun hat. So double up with hat and sunscreen to keep your skin healthy. Click here to see the facial sunscreens I trust – a lifetime of trial and error and a lot of education has made me very particular.
So, the bottom line is – yes, you need sunscreen on your face and ears even when you wear a hat. And, I encourage you to wear a hat. Spring is around the corner (thank goodness) and it’s the perfect time to go hat shopping since stores stock hats for Easter.
What about ball caps?
My patients have heard me call ball caps my job security. I see it all day in my practice, more sun damage on the sides of the face and ears in people who have relied on ball caps when they are outside. Don’t! Please don’t think you are creating enough facial shade when you wear a ball cap. Those hats keep the glare out of your eyes and protect your forehead skin, but that’s it. Wrinkles, uneven pigment, and skin cancers will be abundant and problematic on your cheeks, crows feet, nose, and ears – keeping your dermatologist very busy.