Vitamin D and Sun Bathing

[Frank Hagan]

One of the more controversial points in PPLP is where the Drs. Eades makes the recommendation to get more vitamin D by sun bathing (without burning, of course). Reading the shock of some reviewers on this point has always amused me.

The Wall Street Journal Health Blog has an interesting piece on a couple of new studies showing that kid's are not getting enough vitamin D (http://blogs.wsj.com/health/2009/08/03/study-kids-arent-getting-enough-vitamin-d/). Video games are blamed, of course, but I'd also point to the fact that we slather up kids with sunblock before sending them out for 10 minutes in the yard.

They reference several other studies, including one that they report:

A second study (http://pediatrics.aappublications.org/cgi/content/abstract/peds.2009-0213v1) found that low levels of vitamin D in adolescents are associated with high blood pressure and elevated blood sugar. That study, also published in Pediatrics, looked at data from more than 3,500 adolescents collected as part of the same federal survey.

[mcsblues]

I must admit I have never seen any criticism of the Eades on sensible sun exposure, - their critics seem much more obsessed with the dietary side, but perhaps I just don't bother to look these days.

There is a whole raft of more convincing research now if you check out the Vit D Council (http://www.vitamindcouncil.org/) site and John Cannell's newsletter (http://www.vitamindcouncil.org/releases.shtml) is always an entertaining and thought provoking read (he certainly dissuaded me from regarding cod liver oils as a reasonable source - and in so doing shed some light on the nature of Weston Price disciples ...). The 'doubling' of a recommendation to 400IU is still woefully inadequate, and for anyone living in higher latitudes (35+) any sort of winter sun exposure is insufficient without supplementation.

If you want an eye opener on Vit D and disease prevention (still associative but the numbers involved are shocking) check out this graphic (http://www.imminst.org/forum/index.php?act=attach&type=post&id=6065).

[James L]

Malcolm,

Thanks for the links. Am I correct in thinking that the 400 IU level is way far to the left of the so-called reference level of 25? TIA.

[James L]

Check the WebMD article on this. I think it states that kids should get at least 10 minutes of full-sun exposure every day, before any sunblock is applied.

[mcsblues]

Malcolm,

Thanks for the links. Am I correct in thinking that the 400 IU level is way far to the left of the so-called reference level of 25? TIA.

Well there is no answer to that question - well apart from "it depends" - there are far to many variables - but read this (http://www.vitamindcouncil.org/newsletter/2008-july.shtml) and you will have some guidance - and as John says getting yourself tested before and (at least) after supplementing for a while is the only way to tell. And note 25 is not the goal - the goal is at least 50 - 55 (see the graph) more than 70 if you suffer from, or have a family history of any of the multitude of conditions now linked to lower Vit D levels. He does refer to appropriate doses for children there, but if you can stomach reading about the almost unimaginable experiences some parents endure as a result of undiagnosed deficiency, this post (http://www.vitamindcouncil.org/newsletter/child-abuse-or-vitamin-d-deficiency-rickets.shtml) is very sobering indeed.

Check the WebMD article on this. I think it states that kids should get at least 10 minutes of full-sun exposure every day, before any sunblock is applied.This is meaningless unless the time of year and latitude is mentioned - and as I said before a latitude over 35 in winter, no amount of time would suffice. There is a rough rule of thumb, 'if your shadow is longer than you are, you are not making Vit D'.

[James L]

Well there is no answer to that question - well apart from "it depends" - there are far to many variables - but read this (http://www.vitamindcouncil.org/newsletter/2008-july.shtml) and you will have some guidance - ...Thanks for the link and its info on the major reference labs; good to know.
This is meaningless unless the time of year and latitude is mentioned - and as I said before a latitude over 35 in winter, no amount of time would suffice. There is a rough rule of thumb, 'if your shadow is longer than you are, you are not making Vit D'.What's your basis for this claim? Phoenix is at 33.5 degrees N. You mean that you're only getting marginally adequate sun in the winter there?

As you probably already know, "The skin produces approximately 10,000 IU vitamin D in response to 20–30 minutes of summer sun exposure ...." [Vitamin D Council] I'd rather sunbathe and make my own Vitamin D. :)

[Mitra]

I'm at 53º North. Can't make vit D for a lot of months in the winter :(. And given it's done nothing but rain for the last month of this summer, it's a good thing to have the option of supplements!

I'm trying to remember where I saw a chart of how long the "vit D winter" lasts at different lattitudes. If I come across it I'll post it here.

[mcsblues]

What's your basis for this claim? Phoenix is at 33.5 degrees N. You mean that you're only getting marginally adequate sun in the winter there?
Probably. Again there are a lot of factors. How dark your skin is, whether you are truly sun bathing or just getting incidental exposure on things like face amd arms - which make less Vit D because they are likely to be more tanned ... because they get exposed more often. Not sure where I saw the 35 degree number - might have been John Cannell - I looked, Holick (http://www.uvadvantage.org/Home/tabid/36/Default.aspx) says 40 - but like I said, it doesn't matter - it is what you and your body can do where you are.

As you probably already know, "The skin produces approximately 10,000 IU vitamin D in response to 20–30 minutes of summer sun exposure ...."[Vitamin D Council]Right ... summer ... and again it varies between people and where they are!:p
I'd rather sunbathe and make my own Vitamin D. :)Me too - well sort of - I get bored just lying in the sun, but certainly in summer I take advantage of what is available, but try not to get burnt. But in winter (now!) at nearly 43 degrees south, I take 5000IU a day - more if I have been in contact with the great (flu ridden) unwashed! It's cheap, easy and given the mass of supporting research ... why not?;)