Let me be the first to say: I am pro-sunlight. I’m not talking about weather patterns, either. I’m talking about exposing yourself to some rays. I spend a fair amount of time outside soaking up the sun’s energy (of course, being careful not to burn). Although evidently most dermatologists believe we would be better off spelunking in caves 24/7 and covering ourselves in head-to-toe black garb whenever we venture out, my own evolutionary perspective leads me to believe we were designed to get sunlight almost every day and that our health suffers if we don’t get enough.
In fact, recent studies show that, as a result of our shunning the sun, many of us suffer from Vitamin D deficiency and a resulting loss of bone density and immune function (to name just a few effects). Some researchers opine that more people die from lack of sun than from too much sun! But, I digress.
I came across an article  the other day that piqued my curiosity since it dealt with the combination of running and sunning. It basically showed that marathoners (e.g. formerly yours truly) tend to get skin cancer at higher rates than other people. The more they run, the higher the incidence of skin cancer.
My take on what’s happening is that not only are runners exposed to more sun (which can cause DNA damage in skin cells – ergo, cancer), but they are also bathed in more free-radicals overall from the excessive oxidation of glucose and fats.
We know that sun exposure does deplete the skin of the antioxidant Vitamin C. Stick with me on this: the act of running tends to divert blood flow away from the skin, starving it of additional important antioxidants that could neutralize the free-radical damage in the skin tissues. Add to that the enormous amounts of stressful cortisol marathoners pump out doing this unnaturally high steady-state oxidative work and we not only get the DNA damage, we get the immune-bashing effects of the high-stress activity. The effect: more DNA damage and a reduced ability to recognize that damage and take steps to eliminate those cells and/or repair the damage.
That’s one reason (among many) that I have doused myself with antioxidants inside and out for over 20 years now. That’s also why one of my mantras is: a little running is OK – a lot is bad.
The above article also brings up other points of discussion, such as whether the reliance on inferior sunscreens might be another cause. This is vitally important to discuss and it’s not getting much attention in the mainstream media. It appears that for the past 30 years so-called sunscreens have been good at blocking UVB rays (the ones that burn) but not UVA (the ones primarily responsible for DNA damage and skin cancer). Thank you, FDA. The terrible effect is a generation of gung-ho health fanatics slathering on sunscreen and running 40, 50 or 100 miles a week. The fact that we didn’t burn only lead us to believe we could stay out even longer. Little did we know that the burning of skin might have been a great first warning to get the hell out of the sun! How’s that for nature’s way of saying “Yo! Enough!”? Unfortunately, the sunscreen gave us the false notion we were invulnerable. Oops. Guess big Pharma was wrong again. More on that later….
[tags] sunscreen, vitamin D, free radicals, marathon, antioxidants, DNA damage, skin cancer, UVA, UVB, cortisol, sun block, SPF, immunity, bone density, osteoporosis, dermatology [/tags]