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Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 12:21 pm
by Gilgamesh
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 1:21 pm
by Harrison
Thank you posting this Gilgamesh. I know there have been some threads about this before, but the JAMA Neurology study mentioned in the article (
http://archneur.jamanetwork.com/article ... id=2436596) is yet another thing to consider. Here is the most telling table from the article:
Code: Select all
Normal (n=189) MCI (n=125) Dementia (n=67)
Serum25-OH D level,
mean(SD),ng/mL 19.7(13.1) 20.0(10.3) 16.2(9.4)
Vitamin D status, No.(%)
Deficient<12ng/mL 46 (24.3) 30 (24.0) 24 (35.8)
Insufficient,12to<20ng/mL 66 (34.9) 41 (32.8) 27 (40.3)
Adequate,20to<50ng/mL 74 (39.2) 53 (42.4) 15 (22.4)
High,≥50ng/mL 3(1.6) 1(0.8) 1(1.5)
Basically 75% of Dementia patients are deficient / insufficient for Vitamin D, with less than 20 ng/ml. Still, 59% of cognitively normal are deficient / insufficient. Bredeson calls for trying to hit 50-80 ng/ml, but targeting <50 ng/ml seems to be more prudent to me now. My last measure was 44 ng/ml and I added 1000 IUs to my existing 2000 IU to get into the Bredesen range. Now I'm thinking 44 ng/ml is probably good enough.
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 2:24 pm
by Julie G
I'm curious. Has anyone ever done a good long term prospective RCT on Vitamin D checking for various endpoints (mentioned in the article): bone density, muscle strength, inflammation, arterial function, triglycerides, heart disease, cancer, cognition, mortality- actually checking serum levels?
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 2:27 pm
by circular
Rhonda Patrick has concluded 40-60. I see such conflicting info on this I'm not sure what to think. I was 44 in July, started 2000 IU/day and just tested 44 again. I've read it takes months to build up, but I would have expected a bump. Not sure if it's me or the formula. Doubling to 4000 IU until next bloodwork. I'd at least like to be at 50. I'm holding out to see some massive review on this issue for guidance. Does anyone have time to look?
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 3:50 pm
by RichardS
For a long time I have had this persisting concern that all sorts of chronic conditions for which vitamin D has been flagged as low and a risk factor suffer from a spurious correlation. I have strong suspicions that many of those conditions likely find sufferers more bound to the indoors where personal production of vitamin D is shut off. More than for most supplements, long-term controlled trials of vitamin D supplementation really need to happen. I've seen all sorts of recommendation for vitamin D levels so high that few if any groups studied ever get that high. Nomadic equatorial populations, Mediterranean lifeguards and so on typically are in the 40's, maybe 50's. Even if they were higher, that does not mean 50+ levels are optimal. I can't recall any clinical trials pushing past 50 for a long period. Has anybody else seen such data?
Personally, I've dropped vit D supplementation. Based on Dr. Davis' recommendations, I had gotten it up to low 60's when his recommendations were 60-80. As a previously pasty white Eastern European living in the sunbelt doing near daily midday sun exposure for much of the year, I see my levels in the mid 40's in early summer. I'm having a hard time getting my head around higher levels being necessary for optimal health.
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 3:57 pm
by Gilgamesh
J, no, not that I'm aware of.
All we can be pretty sure of is that below 20 ng/mL is not good. Whether 25 is better than 21, or 30 is better than 25, etc., is really unknown, from what I've read.
Like I've said before, my review of the literature makes me want to aim for high 20s/low 30s.
GB
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 4:04 pm
by Stavia
I'm running at just between 90 and 100 mmol/ml. Divide by 2.5 to get mg/ml. I take 4000IU a day. Its winter here currently. I intend to drop to 2000IU in summer.
I believe its impossible to get a predictable stable level as its impossible to get exactly the same sun exposure every week. And unnecessary IMO.
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 4:14 pm
by apod
I liked Paul Jaminet's book on Diet / Nutrition (from a paleo / ancestral position, fairly high in fat / SFA.) He recommends a fairly conservative 40ng/ml 25ohd3 level, which might add up to around 4,000 IU --
http://perfecthealthdiet.com/recommended-supplements/ Interestingly, he makes some distinction between serum levels for those with European / Asian ancestry (35-50 ng/ml) vs African ancestry (30-40 ng/ml.)
If I recall, D3 balances out against other fat soluble vitamins, namely retinol and k2 (plus other cofactors, like calcium and magnesium, as well as boron an zinc.) Perhaps higher dosages of D3 is less likely to be "overdoing it" when regularly consuming an adequate intake of organ meats, eggs, and dairy fat rich in retinol and k2, with an adequate intake of calcium and magnesium. It seems fairly easy to under supply calcium, magnesium, boron, zinc, retinol, k1, and k2 in the diet, then supplement a ton of d3 leading to issues down the line.
http://www.westonaprice.org/blogs/cmast ... man-study/
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Thu Sep 24, 2015 7:49 pm
by GenePoole0304
do you know about the active and inactive form balance and it's importance related to auto immune response debate??
I will post later..as have something new to post
http://forums.phoenixrising.me/index.ph ... col.26916/
cheers...zzzzzzzzzz....need my beauty sleep....xxxxx
Re: Vitamin D: Don't Overdo a Good Thing
Posted: Sun Sep 27, 2015 2:31 pm
by Gilgamesh
Oh, and then there's the finding that vit. D supplementation might suppress melatonin secretion:
https://www.consumerlab.com/reviews/vit ... #melatonin
(If that's a paywall for you it should be pubmedable.)
GB