Right now your hands are teeming with bacteria. Countless trillions of organisms call your skin home, and that’s a good thing. Skin infections do not arise because you have bacteria on your skin. Rather, they arise because the type of bacteria on infected skin is not healthy bacteria but aggressive pathogenic bacteria.
Determining which bacteria are good and which are dangerous is difficult, but our immune systems have managed to get it right most of the time. When our immune systems are wrong, either an infection develops, or excess inflammation develops, as is the case in eczema or psoriasis.
Telling good from bad is hard. There are hundreds of types of bacteria on your hands right now. A recent study of college students (perhaps not the cleanest group of individuals) discovered that the average student has 140 different types of bacteria on his or her skin. There were over 4,000 different types of bacteria identified across all the students. Not surprisingly, the most common types were familiar household names: Propionobacterium (the bacteria responsible for acne), strep, and staph (of which the infamous methicillin resistant staph aureus, MRSA is a subtype).
There were also differences in the bacteria on the dominate hand versus the non-dominant hand — namely bacteria normally found in the gastrointestinal track was found more often on the dominant hand. This will no doubt lead to a follow up study of: “Do college students wash their hands before leaving the bathroom?” (Research so far does not look promising).
Photo: Pink Sherbert Photography (flickr)
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)
You might be getting some UV exposure long after the sun goes down — some new fluorescent light bulbs give off UV light.
Fluorescent light bulbs are everywhere now that people are trying to be more green. Most popular are the ice-cream-twist compact fluorescent bulbs called CFBs. CFBs create light by energizing a gas and exciting a phosphorous coating on their glass. The coating prevents most of the ultraviolet light from reaching you, but not entirely; some UV radiation leaks out of any fluorescent bulb. In some CFBs, the emission of UV light is so high that it exceeds the safety limits of the International Commission of Non-Iodizing Radiation.
So, should you be applying sunscreen before turning on your CFB reading light at night? No. Nor should you switch your CFBs back to energy wasting incandescent bulbs. The amount of UV exposure that you get from the light bulb is small compared to the UV exposure you get from just being outside; for most people it is not significant.
However, some people are exquisitely sensitive to ultraviolet light. Auto immune diseases such as lupus, inflammatory disease such as rosacea, and certain drugs such as HCTZ can be triggered by even small amounts of UV light from CFBs.
If you are particularly sensitive to UV, then select CFBs that have a double envelope instead of single, as it will block most of the UV light. And always stay at least one foot away when using fluorescent bulbs of any sort.
Also, remember to sit back from your TV (which my mother taught me to do when I was a kid). Of course, now with HDTVs, you get the best picture when you’re sitting a distance of 3 times the diameter of your TV. If you just bought a 60 inch HDTV, you might need to be in your neighbor’s living room to watch it. This, fortunately, should be safely away from any radiation.
Photo: Steven Fernandez (flickr)
Cold, dry air and indoor heating make winter the season for dry skin. It’s more important now than any other time of year to protect your skin from dryness. The first way to do this is to limit the damage you do to your skin everyday. Some things, like the weather, you cannot control. But, some of the things you do everyday to your skin might be making already dry skin much worse. One area where you can make a big difference is in the shower. Read more…
Seems like everything is linked to cancer these days.
Well you can add flip-flops to the list — I’m sure my mother is throwing hers away right now. Read more…
