Understanding Ultraviolet Radiation (UVR)

Skin that has seen some sun

People are always asking me what they can do to keep their skin from aging. The simplest answer to that question is to avoid overexposing your skin (your face, in particular) to ultraviolet radiation (sun). I know this is not an easy task, especially when so many activities are enjoyed outdoors in the sun, but if your goal is “anti-aging” you will have to adopt behaviors that support that goal.

When some clients hear me talk about sun exposure and how to protect their skin, I think they hear me saying, “Never go out in the sun.” And that, obviously, is simply not possible—or desirable. It is not about avoiding all exposure, it is about understanding the short- and long-term effects of exposure and how to avoid damaging your skin while enjoying a life spend out of doors. As we all know, too much of a good thing can turn bad. And so is true with sun exposure. Any time you receive ultraviolet radiation (UVR), you are exposed to the negative effects of the sun: waves of radiation coming down from millions of miles away, adversely affecting your skin.

Protection, reapplication, and wisdom are at least three of the components to keeping your skin from getting too much sun.

• Protection comes through the use of sunscreen, staying in shaded areas when possible, and keeping a hat on and/or protective clothing—especially when you know you’ll be exposed over a long period of time.

• Reapplication of sunscreen is so important, but I believe this step is usually avoided or ignored. If you are going to have extended time in the sun, taking along your sunscreen is a must. This way you can reapply frequently (and liberally). You can find travel-sized sunscreens at Target and other retail outlets that sell sun protection products. 

• Wisdom comes into play because without it, UVR will get the best of you. How many summers have you seen people who either fell asleep in the sun or otherwise ignored the fact they were getting over-exposed? Soon after they are walking around in pain and hosting a deep red sunburn. (Aloe vera would really save their skin!) Be smart. Don’t get overexposed. Don’t get caught without protection (whether clothing or products) and keep your UVR exposure to a minimum.

Remember: Sun damage is cumulative. Each year (each day) you rack up more sun damage points, which down the road could equal skin cancer. The following was adapted and used with permission from the American Academy of Dermatology. This information is important to keep in mind in your day to day life, even if you aren’t “sun bathing.”

• Shade only lessens UVR exposure. Sunburn from scattered or reflected UVR can still occur in shaded areas.
• Certain surfaces reflect UVR. Water reflects up to 30% of UVR; dry sand up to 18%; concrete 12%; and grass 5%.
• UVR increases with altitude.
• 70-80% of the total UVR from the sun on a midsummer day is received between 9am and 4pm.

• UVR damages the eyes. A wide brim hat reduces the amount of
• UVR reaching the cornea of the eye by 50%. Sunglasses, if UV protective, can filter out as much as 95% of UV rays.
• SPF 15 sunscreen protects against 93% of UVR. SPF 30 protects against 98%. As you can see, the difference between the two are not great. Therefore don’t be as concerned about the SPF number on your bottle of sunscreen; do concentrate on applying enough sunscreen and, if exposure is prolonged, you must reapply frequently.
• Medication can make your skin more sensitive to UVR.

You can prevent (or at least curtail) UVR damage through limited or protected exposure. Please take this information to heart, and always wear sunscreen!

For more information, see:

• Sun Protection: UV spelled out
• My Sunburn Preparedness Kit for some useful tips to help keep your skin safe and sunburn-free all year round
• Hats, Hats, Hats! Protect your skin in the sun

I like it!