Formula Sun – Not Too Much, Not Too Little

Have you ever had a friend tell you that they just want to “Melt on the Beach“?

I have!  And guess what happened on that sunny, Costa Rician beach just north of the equator… The Sun did Sun things! He tempted the almighty with minimum lotion, maximum surface area and a direct line of sight, sorta like..

And right around mid-afternoon he realized the terrible mistake he had made, running to the cover of the trees , but it was simply too late. His skin swelled, puffy red, to a point that no amount of aloe could ease his foolish wounds. The days after brought blisters, pealing, and once back to New York, the dermatologist delivered the recommendation that he should probably not expose himself to the sun for more than 20 minutes at a time….For The Rest Of His Life! If only we could have somehow tracked his Vitamin D production to see if that one epic burn could provide a sufficient supply for the year.

But the Sun’s not all that bad, it’s actually the reason we’re all even here, its the energy source which first established life, and has certainly been pretty damn important as cellular organisms have made the transition from single-celled to the complex lifeforms we see today.    For the 200,000 years of known human existence, the sun has been the focal point of many decisions we’ve made along the way, even to this day we still turn our clocks forward and back to honor its greatness (or something to do with farming, either way).   But as we’ve advanced through recent history (the past 200 years), we’ve slowly evolved into living more sheltered lives, being exposed to less and less Sunlight, prompting experts to ask:  Could Sun Exposure (or lack thereof) be an influencing factor in this wave of 21st century disease?

Why the Sun is our Friend…

Like I said before, the Sun is pretty much the facilitator of life, even though at this point we may be able to find ways (with today’s technology) to survive without it, the world would fall into a state of chaos, like right out of Book of Eli.  So good thing we have the Sun, because we wouldn’t have gotten all this way without it. We’re finding out that many of our innate biological functions have evolved to be truly optimized when in-sync with that big ol’ ball of of fire.

First off, the Sun is the natural regulator of our sleep/wake cycles or circadian rhythms. When natural light hits the retina,  gene expression throughout our body begin to adjust, optimizing for day-time functioning. Serotonin (a feel good neurotransmitter) increases and melatonin (our sleep hormone) decreases, explaining why simply getting some sun first thing in the morning can help jump-start your day!   Several studies have shown that an insufficient dose of daily/weekly sun can be a driver to depression (1). Seasonal Affective Disorder (SAD), is the relation between depression and the change in season, the theory suggests that the change in available sun (daylight hours) as well as the decrease in direct skin exposure (due to more of the body covered-up in cold months) is the reason we may feel the “winter blues” (4).

For humans, sunlight is also critical for the in-house production of Vitamin D, an essential vitamin that’s associated with aiding bone health, elevating mood, decreasing metabolic syndrome (obesity, diabetes, heart disease, stroke), lowering hypertension and immune suppression (which can be good or bad) (2,3).  Observational studies have also pointed out association between low sun exposure and higher risk of all-cause mortality(4). So We Need Sun!….But just make sure you don’t go overboard.

But the Type of Friend that can get on our Nerves…

Ultraviolet Radiation (UVR) is the one main blemish on the suns otherwise impressive resume. It’s broken out into three spectrum’s, two that can traverse the earths atmosphere and reach us – UVA  and UVB. Both of these can (and will) wreak havoc on our body if exposed, unprotected for too long.  The main dangers from over-exposure of UVR is skin cancer, skin burning, ocular disease, and an increase in DNA damage(2,5).  I think we’ve all fallen victim to getting a little to much sun at some point in time, shaking (or pealing) it off after a few days of uncomfort, adding some halfhearted self talk to remind ourselves to wear sun screen next time. But right on cue, we end up in the exact same position next summer. The scary part is, the more burns we experience early in life, the higher the risk of developing  cancers like melanoma down the road (6). Excuse me while I go grab some sun screen….

Lather Up…

The recommendations from the World Health Organization (WHO) advise that  5 to 15 minutes of sunlight on your arms, hands, and face 2-3 times a week is sufficient for getting your Vitamin D fix.  As for the rest of the time, get your SPF On!  A “Physical”,  water resistant SPF 30, which blocks 97% of the sun’s rays is a good place to start. The exact dose varies based on skin type and geographical location but it’s recommended to lather up either way, the damage adds up.

If your not a sun person, there are other ways to obtain your dose of vitamin D. You can turn to fortified foods (milk, cereals, etc..), fish, meats, mushrooms (dried in the sun) and of course supplements to get the job done. So some form of supplementation is probably a good idea (only if they’re healthy of course) if you find yourself associating with Howie from benchwarmers.

Sun exposure truly fits into the “In Moderation” category. If you’re too far on either side of the curve you could very well be putting yourself in harms way.  As always, it comes down to the fact that everybody’s different, what’s optimal for one, very-well may not be optimal for their neighbor.  It’s about have the the knowledge to make educated, good, healthy choices day-in and day-out. There are no guarantees, but there are odds, manipulable odds, so don’t count out the power of the “little things“,  they can very-well be the reason your still boogieing  on the dance floor in 40 years…