- Mark's Daily Apple - http://www.marksdailyapple.com -

Dear Mark: Sunglasses and Sunlamps

Posted By Mark Sisson On December 29, 2008 @ 7:51 am In Dear Mark,Health,Prevention,Sun Exposure | 26 Comments

Dear Mark,

We’re heading into the winter months (it’s chilly even here in Atlanta!) and the days are getting shorter. As “Lights out: sleep, sugar, survival” [7] taught us, we’re wired to handle seasonal patterns of sunlight exposure. What are your thoughts on maintaining a tan year round? Would you be better off letting your tan wane in the winter and switching from regular fish oil to cod liver oil to compensate for the vitamin D? To maintain a tan in the winter months would probably require a tanning booth, and I’d be curious to hear your thoughts on using those, even very occasionally. I’d love to see an article discussing this topic if you can get around to it. If you’ve already written one, could you point me in the direction of it?

Thanks to Keenan for the timely question. Old Man Winter has spread the chill to just about every corner of the country this past month. (Some of you obviously bear the brunt, I know. My condolences…. Having come from New England, I feel your pain.)

First, let’s take the suntan element out of the equation and focus purely on vitamin D deficiency, which has been associated in population studies with certain cancers, MS, Parkinson’s and rheumatoid arthritis. Although time in the sun offers some added color (particularly to the fair-skinned among us), it’s not really the tan itself that’s healthy.

There are two kinds of ultraviolet rays at play here: UVA and UVB. Essentially, UVA rays penetrate more deeply, allow the skin to tan, and are the main (sun-related) culprits behind skin aging. UVB rays don’t penetrate as deeply, are responsible for sunburns (when we overdo it on those mid-winter beach vacations) but have more to offer health-wise, particularly the triggering of vitamin D production. (UVB rays are considered the guilty party in most skin cancer; however, UVA ray exposure is associated with melanoma, the most deadly form of skin cancer. Note: wise antioxidant supplementation [8] goes a long, long way in reducing or eliminating any damage caused by sun exposure.) While the sun offers a generous dose of both kinds of rays, tanning booths generally favor UVA rays (as much as 95% of the calibration – not even close to the UVA/UVB ratio of sunlight) because, well, they’re “tanning” businesses. Their customers are paying for a tan, and that’s what the salons are going to give them.

I’ve never really been a big fan of tanning beds, but I realize the business has over the years changed somewhat. Some “health-conscious” salons now calibrate their beds to offer less UVA and more UVB rays for their customers during the winter months. If you can find such a salon then it might be worth your money. Still, I’ll admit, there would likely be that nagging question in the back of my mind: am I really getting what’s advertised?

A better bet, I think, is just getting outside whenever possible. I also believe it’s safe to say that Grok would agree. Though our Northern ancestors didn’t spend as much time lounging in the sun as their more Southern counterparts during the winter months, they also weren’t the indoor hermits we moderns often are. They had work to do, wood to gather, animals to hunt, skin or cook. Only so much could be done in the confines of their “indoor” shelters. (With the advent of attached garages, parking ramps, skyways, underground pedestrian tunnels, we on the other hand have the ability to avoid virtually any time outside.)

As unappealing as it may sound some days, I suggest getting out on all but the most blistering cold days for 15-20 minutes. Ideally, go out at mid-day when the sun’s position allows you the most benefit for your efforts. If you make it an active time, of course, you’ll have the advantage of some added exercise and a warmer experience. The warmer you are, the more eager you’ll probably be to bare additional skin for some rays.

I always suggest upping your vitamin D nutritional intake during the winter months, particularly if you live in a colder area of the country. I don’t consider it a substitution for the real deal (sunlight), but it’s a help – a supplement to your other efforts.

“Light boxes” or full-spectrum lights (the authentic ones that truly include UV rays) are another option. The studies I’ve read have shown some moderate gains with the use of these lights in terms of vitamin D production, but it’s clear they aren’t as effective as good, old-fashioned sunshine. In extreme situations (submarine assignments, Arctic living, etc.) or for certain conditions like depression, they seem to be a good option. Obviously, light boxes would also be the main alternative for the few who don’t respond to nutritional D supplementation.

Dear Mark,

I took a road trip a couple of weeks back without sunglasses after my sunglasses broke and I backed off from buying another one thinking that it may be primal to drive around without them. Since then I have been holding off buying one. At one point I was thinking of buying some even for my regular runs during the weekend. What are your thoughts on sunglasses? Didn’t our forefathers go out in the sun and survive without sunglasses?

Thanks to Jayadeep for this question. It’s true that Grok et al didn’t go around in Ray-Bans. Some people talk like you’ll fry your eyes if you so much as step out to get the mail without them. Not so. Bright light exposure is important for regulating circadian rhythm. That said, we generally live longer than Grok did thanks to medical care, safety from animal predators, etc. (The guy had the genetic potential, but the saber tooth tiger down the road had other plans.) The main concern is the healthy aging of the eyes – avoiding retinal damage, advanced macular degeneration, and cataracts, which affects nearly half of people between the ages of 70-80 [9].  With longer life expectancies comes the wise alteration of certain practices. I’d include sunglasses in that category. But let me add that research here again supports the importance of high antioxidant levels for sun exposure and eye health [10].

Additionally, there’s the issue of a waning ozone layer and the resulting increased UV exposure, particularly in certain parts of the world like Australia and Southern Chile. (Another example of balancing what fit in Grok’s day with what has changed in ours.) Those with lighter eyes (blue, gray) are more sensitive to light and should take the most precaution.

As always, thanks for your questions and comments, and keep ‘em coming!

Daniel Greene [11] Flickr Photo (CC)

Further Reading:

Don’t Let “D” Stand for Deficiency [12]

Getting Back to Nature [13]

Grok Didn’t Take Supplements So Why Should I? [8]


Article printed from Mark's Daily Apple: http://www.marksdailyapple.com

URL to article: http://www.marksdailyapple.com/sunglasses-and-sunlamps/

URLs in this post:

[1] Start Here: http://www.marksdailyapple.com/welcome-to-marks-daily-apple/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_start_here

[2] Primal Blueprint 101: http://www.marksdailyapple.com/primal-blueprint-101/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_pb_101

[3] free weekly newsletter: http://www.marksdailyapple.com/subscribe-to-blog/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_newsletter

[4] books: http://primalblueprint.com/categories/Store/Books-and-Media/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_books

[5] support options: http://primalblueprint.com/categories/Store/Services/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_services

[6] supplements: http://primalblueprint.com/categories/Store/Supplements/?utm_source=mda_wwsgd&utm_medium=link&utm_campaign=mda_wwsgd_supplements

[7] Lights out: sleep, sugar, survival”: http://www.amazon.com/Lights-Out-Sleep-Sugar-Survival/dp/0671038680

[8] wise antioxidant supplementation: http://www.marksdailyapple.com/definitive-guide-to-primal-supplementation/

[9] affects nearly half of people between the ages of 70-80: http://www.sciencedaily.com/releases/2008/04/080417155909.htm

[10] the importance of high antioxidant levels for sun exposure and eye health: http://archopht.ama-assn.org/cgi/content/abstract/126/10/1396

[11] Daniel Greene: http://www.flickr.com/photos/danielgreene/344196890/

[12] Don’t Let “D” Stand for Deficiency: http://www.marksdailyapple.com/vitamin-d-deficiency/

[13] Getting Back to Nature: http://www.marksdailyapple.com/getting-back-to-nature/

Copyright © 2009 Mark's Daily Apple. All rights reserved.