Sam turned pink right away, then the next day a light brown. His brother, Zach, was covered in fine pink pinpoint bumps that itched. Both my nephews left the cold Iowa winter weather last week to play some golf with my parents in sunny Arizona. After 3 days and 90 holes of golf, they both got more than a little sun, but thankfully no burns. Why the different reactions, and how does the sun brown, burn, and age the skin?
Ultraviolet (UV) rays from the sun cause direct damage to the DNA in the skin cells, leading to cell death and inflammation. This can occur in the superficial layer of skin, or epidermis, as a first-degree burn. If the damage goes deeper, into the dermis, it becomes a second-degree burn.
Sun damage triggers the body to go into repair and prevention mode, cleaning up the inflammation and oxidative damage, repairing breaks in the DNA, and turning on the dark melanin cells that replace the dead burned skin cells. The darker skin forms more of a protective barrier to UV damage in the future.
At the least, the UV rays cause a mild burn, which typically turns pink within a few hours. Then it may take a few days to a week for the skin to start to darken from increased melanin cells. With more damage, however, the burn causes pain and swelling that presents later the same day and continues for several days. The damaged outer layer of skin sloughs off as peeling skin 3 to 7 days later.
Some people have an allergic reaction to the sun, called photosensitivity or sun induced urticaria. My nephew, Zach, had a little of that. It usually goes away, and suntan ensues, but for some people it’s a chronic issue that plagues them with even slight sun exposure.
If the sun damage is severe it can cause systemic illness, with nausea, fever, chills, and light-headedness. In extreme cases it is life threatening.
UVA and UVB Damage
There are two types of UV rays of concern with skin, UVA and UVB. The UVB rays cause the notable sunburn, while UVA especially leads to deeper damage, skin cancer and aging. UVB is mostly a concern during summer months and peak daylight hours, while UVA is harmful year-round, all day long, even penetrating through glass. Most people have more sun damage on the left side of the face from years of driving.
Chronic UVA exposure causes “photo aging”, a process that thickens the outer layer of skin, destroying the elastic properties and causing cell death that leads to dark or light spots.
If the UV damage is severe, and/or chronic, then the body’s repair mechanisms can’t keep up and skin cancer occurs. Cumulative sun exposure leads to basal cell and squamous cell cancers. I surgically remove them almost every day from the face and arms of patients. Mostly I see these in outdoor enthusiasts and those whose occupation is outdoors, such as ranchers.
Melanoma is the most worrisome skin cancer, as it will more likely spread. Intense, intermittent sunburns are more of a risk for melanoma, and even one blistering sunburn doubles the chance for melanoma.
Protect That Precious Skin
Be sure to keep all of your skin protected with a sunblock. The only ingredients that truly block both UV rays are the physical sun blocks, zinc oxide or titanium dioxide. The numerous chemical sunscreens not only don’t block both UV rays but are also linked to hormone disruption, cancer and other health issues.
UV rays also promote damage to the eyes in the form of cataracts and macular degeneration. Wearing sunglasses that block UVA and UVB rays is a must. Beware of sunglasses that don’t block both rays, as the pupil of the eye will dilate behind dark glasses and let even more harmful rays into the eye.
A diet rich in anti-inflammatory and anti-oxidant foods helps the skin’s defense mechanisms. That means more fruits and veggies. Anti-oxidant supplements such as Vitamin C and E have some evidence for skin protection from UV rays.
Stay out of the mid-day sun from about 10am to 4pm. My favorite sun protection is called shade! Wear a broad brimmed hat, long sleeve shirt and pants. The new SPF clothing is awesome and actually keeps you cooler by keeping the UV rays from heating the skin.
Apply sunblock on areas that can’t be shaded. It is best to apply lotions quite liberally, 15-30 minutes before exposure and reapply 30 minutes later. Swimming, sweating, etc. will wash off the lotion so reapply frequently.
We love the Colorado sunshine, and we love being outdoors, but avoid the burn, prevent photo aging, and have some fun in the sun.
Author
Scott Rollins, MD, is Board Certified with the American Board of Family Practice and the American Board of Anti-Aging and Regenerative Medicine. He specializes in bioidentical hormone replacement for men and women, thyroid and adrenal disorders, fibromyalgia and other complex medical conditions. He is founder and medical director of the Integrative Medicine Center of Western Colorado (www.imcwc.com) and Bellezza Laser Aesthetics (www.bellezzalaser.com). Call (970) 245-6911 for an appointment or more information.
