On a cold, cloudy, or rainy day we long for the feel of the sunshine on our faces. There is a comforting feeling imparted by that warmth we feel. We look with envy at the tanned models on the covers of the magazines in the check-out lines of the grocery store. There is something intriguing about the sun. Historically, people have worshipped it, and it seems no different even now. OMG! We pay money to get artificial sun exposure by being closed in a tanning bed.
BEWARE! Overexposure to sun is harmful. Sure, most people recognize that staying out in the sun too long results in a painful sunburn. Simply stated though, any change in skin color (sunburn or tan) caused by the sun or a tanning bed is an indication of damaged skin. Let’s learn why…
Radiation from the sun can be divided into three wavelength types – ultraviolet, visible light, and infrared. Visible light is obviously what we see, and infrared is the invisible radiation we feel as heat. It is ultraviolet radiation (UV) that causes skin damage. UV is divided into three types – UVA, UVB, and UVC. UVA penetrates the atmosphere; whereas, most of UVB and all of UVC are absorbed by the ozone layer. The amount of UV radiation reaching a person depends of several factors. The most intense UV occurs at solar noon which is when the sun is at its highest point of the day. 75% of all UV received during a day occurs 3 hours before and 3 hours after this time. The amount of UV radiation also varies during different seasons of the year and according to geographic latitude. The amount of UV radiation increases in the summer and the closer one gets to the equator. Since the atmosphere is thinner at higher altitudes and less able to absorb UVB, there is more UV radiation at higher altitudes. Although weather conditions also have an effect, clouds do not reduce the amount of UV as much as visible or infrared light.
There is also risk from reflected UV rays off surfaces and the terrain. Smooth surfaces whether dark or light in color typically reflect more that irregular surfaces. The UV radiation reflection is greatest off water, dry sand, and fresh snow. Now you know why a person skiing at a high altitude during lunch on a cloudy day in fresh powder is at great risk for sunburn.
There are acute and chronic health effects of exposure to UV radiation. The only good effect of UV exposure is the photosynthesis of Vitamin D. Since only a brief daily exposure to sunlight is required for this positive effect and since Vitamin D needs can be adequately addressed with oral supplements, the risk of sun exposure far outweighs this one benefit. UV exposure stimulates the skin to produce more melanin which results in a tan. Although melanin has a protective effect, any increase indicates some acute skin damage has occurred. However, it does explain why light skinned individuals are most susceptible for sunburn which is the most important acute injury to the skin caused by UV radiation.
Chronic health effects of sun exposure include photo-aging. Exposure to all UVA and UVB results in the breakdown of elastic fibers in the skin resulting in a wrinkled, leathery skin appearance with aging. Solar radiation also damages the eye over time and places a person at risk for developing cataracts or macular degeneration. The most common risk of overexposure is the development of skin cancers including basal cell and squamous cell carcinomas and melanoma which is the most dangerous and lethal type. The incidence of skin cancer is currently growing faster than any other form of cancer. In 1937 the chance of getting melanoma was 1 in 1500. In 2007 that chance has increased to 1 in 63, and it is occurring in younger individuals. This increasing incidence is thought to be due to the decrease in the ozone layer, the change in dress patterns that favor more skin exposure, the greater opportunity for leisure activity, and the increase of artificial sources of UV radiation for tanning purposes. Since the development of these skin cancers is directly correlated to over-exposure to UV radiation, it can be prevented. It is estimated that 25% of all UV radiation exposure occurs before the age of 18. Therefore, protection from the sun needs to begin in infancy and continue through one’s life. Although sun screen is the most commonly used method of protection, one should not rely on sunscreen alone.
Basic recommendations for sun protection are:
- Avoid play outdoors at midday from 10 AM to 4 PM when sun rays are strongest.
- Play in the shade as much as possible especially infants less than 6 months. Pay attention to the surface of the play area realizing that playing in grass or on mulch is less of a problem that in sand or around water. Beware of reflective exposure as well.
- Dress children in light colored, loose fitting clothes that cover as much skin as possible. Light colored and loose fitting clothes will lessen the chance of getting too hot. Cotton fabrics are the best. Get a fabric that is tightly woven. Hold the cloth up to the light. A tightly woven fabric will not let much light through.
- Wear a hat with a brim to shade the face. A hat that has flaps to protect the neck and ears is the best. The popular baseball caps provide no protection to these areas.
- Wear sunglasses to protect the eyes.
- Use sunscreen on all children over the age of 6 months. The best protection for an infant less than 6 months is to stay out of the direct sun and wear protective clothing including a hat and sunglasses. If adequate clothing and shade is not available, apply sun screen only to small areas exposed the sun.
- Use a SPF (Sun Protective Factor) of 15 or greater. The American Academy of Pediatrics recommends at least an SPF of 30.
- Select a broad spectrum sunscreen that contains inorganic filters. Zinc oxide and titanium dioxide are inorganic and protect against both UVA and UVB.
- Especially in infants, test a small area on the back to see if a rash develops before using applying the selected sunscreen generally.
- Apply 20-30 minutes before going outside to all exposed areas to get maximum protection.
- Reapply after swimming and every 2 hours. Even water proof forms must be re-applied in this way.
- Sunscreen is not meant to allow kids to spend more time in the sun than they should otherwise.
Research studies have estimated that sun avoidance could reduce the risk of skin cancer by as much as 80%. Since much of the exposure occurs under the age of 18, it is our responsibility as parents to instill in our children good practices to avoid over-exposure to the sun. Best practices and habits are developed in us as children. Enjoy the summer months and remember to avoid being out in midday if possible, wear protective clothing including hats and sunglasses, and apply sunscreen repeatedly.
As I always tell my children……”Have fun but be safe!”
Photo credit: Photo by crazydog12 & used with permission from www.sxc.hu