Where Are You More Likely To Sunburn: Beach Or Mountains?

While vacationing in Idaho and Montana last week (blissfully off the grid), I experienced something beautiful: altitude. At 6,260 feet Stanley, Idaho is a mile higher than my home in San Diego. The skies there were a brilliant blue. There was daylight well after 10 PM. The mornings were a chilly 35 degrees. And I got sunburned.

How can this be? Montana is over 1,000 miles north of San Diego. Shouldn’t the sun be stronger down here?

Several things determine the sun’s intensity. The closer to the equator you are, the more intense the sun’s rays. But also, the higher up you are, the more intense the sun’s rays. Your UV exposure increases by 10% for every 3,280 feet in altitude; at 6,000 to 8,000 feet in elevation, you’re exposed to 25% more ultraviolet radiation than at sea level.

Also, snow (which fell during our mid-June trip) is an efficient reflector of sunlight. When skiing or hiking in snow, 80-90% of UV light is reflected at you, dramatically increasing your sun exposure. Grass in comparison reflects only about 3% of sunlight.

Water, especially when still, also reflects sunlight. Still lakes, including the beautiful Yellowstone Lake pictured above, can reflect up to 100% of UV light (hence the term mirrored lake), doubling your UV exposure.

So although you might feel hot lying on the beach in June in Southern California, you might be more vulnerable to sunburn on a chilly hike in Yellowstone after a June snowstorm, which is exactly what happened to me. (Hence the Stetson later in the trip…)

Photos: Madsit, Stanley, ID (top) Purticortico Yellowstone Lake, WY (middle) Dermdoc White Bird, ID (bottom).

Caffeine Protects Against Skin Cancer


So how does a dermatologist like me protect against skin cancer? I go to Peet’s Coffee.

There are plenty of reasons to enjoy a cappuccino in the morning (if you can still afford it), and preventing skin cancer might be one of them.

Studies of mice have shown that feeding them caffeine protects them against ultraviolet radiation, which is similar to sun exposure for humans. The protection is most effective when the mice exercise. (So the researchers basically make them drink espresso then hit the exercise wheel.)

While epidemiologic studies and animal studies are helpful, it is nice to have a scientific explanation to support the claim. New studies show how it works.

Researchers exposed skin cells that were growing in culture to caffeine (possibly when one of the graduate students spilled his Red Bull on the petri dish). They then exposed the cells to damaging UVB light. They found that the caffeine-treated, UV-damaged cells underwent programmed cell death. When cells are damaged, but don’t die, they grow into cancerous tumors. When damaged cells die, they are no longer a threat to the body and are safely eliminated.

As sunscreens become more sophisticated, ingredients like caffeine will be added to soak up the damaging oxidants or to protect the skin from developing cancer. Botanicals like ferulic acid, derived from ferns, have proven themselves as powerful additives to sunscreens and are the future of sun protection.

Although there is not enough evidence to advise patients to drink more coffee as a means of sun protection, do you really need another reason to have a nice macchiato in the afternoon?

Photo: Burnt Phrases (flickr)

UV Light for Acrylic Nails Might Cause Skin Cancer


“It’s like a mini tanning bed for your fingers. ”

Artifical nails are a $6.3 billion dollar industry. There are nearly 60,000 nail salons in the US — 5 times as many Starbucks! Many of these nail salons use UV light, which might increase the risk of skin cancer on your fingers.

Researchers from the M.D. Anderson Cancer Center at the University of Texas noticed that some of their patients with skin cancer on their fingers (an uncommon place to get skin cancer) reported having had UV light for artificial nails. Such UV light has been shown to damage cells’ DNA (the genetic code in all cells) and to cause mutations that lead to skin cancer.

There are several types of nails. The most popular is acrylic, a two part process where a liquid monomer is combined with a powder polymer. It hardens in seconds, but takes an hour for the final hardness to set. Ultraviolet light is used to speed up the hardening.

A second type of artificial nail is the UV-gel. These are more flexible and have a high-gloss finish than acrylics. As their name suggests, ultraviolet light is used to harden the nails.

UV light is also used for a topcoat sealant. Because artificial nails yellow from UV light (especially tanning booths), a top coat can be used to protect the nail. This topcoat is cured (or set) using UV light.

The amount of radiation that your fingers get from the nail treatment is comparable to what you would get in a tanning booth. Because nails are done every 2-4 weeks (one would hope), that can add up to a significant amount of UV exposure over years.

No large scale studies have been done to examine the danger of using UV light for nails, but these patients suggest that there is likely a risk, especially if you have fair skin or have a history of skin cancer.

Photo: Monibela (flickr)