Vitamin D and ME

Vitamin D and ME, should pwME have high vitamin D?

I've been told ME/CFS patients should have vitamin D levels >100 nmol/L. Does anyone know where this could originate from? The highest vitamin D levels recommended in any guideline I am familiar with is >75 nmol/L, and I am not aware of research that says there are any reason to go beyond this for anyone.

I found one small study on vitamin D supplementation and vascular health in ME/CFS that found no benefit of vitamin D, and one prevalence study on vitamin D deficiency in patients in North-west England.

 

Yes, below 25 nmol/L we get skeletal deformities; rickets in children and osteomalacia in adults. So most countries have a lower reference range between 30-50 nmol/L to cover any potential extraskeletal effects of vitamin D. Those who most strongly believe in the extraskeletal effects have reference values >75 nmol/L. In Norway the lower reference is 50 nmol/L, I wonder if it'll increase when guidelines are revised soon.

That pwME should have >100 nmol/L have shown up a few times in ME/CFS groups I'm in and I can't get a reference for it besides "It's shared in many ME/CFS groups".

 

I was told this as well by a Dr who is knowledgeable about ME. Vitamin D was literally the only thing my GP followed up after I’d had my consultation with the ME Dr. I’m pretty certain my result was around at 70/75 at that time which the GP said was perfectly ok despite being towards the lower end of the reference range and what the ME dr had said. A couple of years before I had scored about 50. GP Didn’t even suggest supplements.

Since then th NHS has actually said a couple of years ago that people here should supplement vit D in the winter. And supplementing Vit D was quite actively pushed last winter in the context of Covid. All my elderly rellies are now on it.

I was already supplementing Vit D when I scored 70ish so apart from trying to get outside if possible didn’t really know what else I could do about it.

 

Coming from the northern part of Norway, where many are insufficient, that is not my experience. My GP's have often been very mistaken about how easy it is to get adequate vitamin D. I do somewhat enjoy being told that eggs and butter is a good source of the vitamin though, and that the sun in march is able to provide any useful contribution to vitamin D stores (never mind the amount of clothing people wear at that point). Makes me feel that dietitans are indeed needed

 

I know many with MS that have been recommended to have vitamin D levels >75 nmol, and they also recommend that at the university I'm at. I wouldn't really mind if pwME were told the same, but I don't see where the >100 nmol/L value comes from.

 

I wish more doctors knew more about vitamins.

Thanks!

By skimming the names of the references from grassroothealth I'm not so sure about the conclusions made, a comparison of a group with 20 ng/ml to a group with 40 ng/ml cannot say if a level of >30 ng/ml is enough. Will have to read them a bit more carefully

In the guidelines from the endocrine society which the Harvard site seems to quote, it says >75 nmol/L or >30 ng/L as the cutoff for insufficiency, while it is said at the very end that "For clinical care, it appears that all current methodologies are adequate if one targets a 25(OH)D value higher than current cut points; for example, a value of 40 ng/ml is without toxicity and virtually ensures that the individual's “true” value is greater than 30 ng/ml."
So it's an argument to be on the safe side due to different measuring methods (which of course also means that the data used to make these guidelines can have wrong "true" Vitamin D levels). This reminds me that I did have a patient as an intern with vitamin D >100 nmol/L (40 ng/ml), and he said it his GP said his numbers were great.

 

I haven't checked out the study but people interested in insulin resistance and Type 2 diabetes might want to check out this recent NZ study:

 

Are you sure it's recent? I find an article of hers from 2009 with 235 South Asian women from Auckland. Notably, to be included in the study these women had to be insulin resistant, vitamin D deficient (defined as <50 nmol/L) and not take vitamin D supplements of >25 mcg/day. After six months of supplementation median vitamin D had increased from 21 nmol/L to 75 nmol/L in the supplement group, and they had improved insulin markers compared to those who received placebo. Endpoint vitamin D levels >80 nmol/L had the highest effect on insulin resistance.

However, at the end of the study the insulin resistance is similar between the two group, the statistically significant finding was that the change between groups were different (Vit. D group: From 1.5 to 1.7, the placebogroup from 1.7 to 1.5). I'm not sure I would call that clinically relevant, but I'm not familiar with insulin and glucose measurements for this population (it can be different between ethnic groups) so there might be some cutoff values I am not familiar with. That the vitamin D groups at endpoint had the same values as the placebogroup had at baseline makes me think it is not that important (they were after all deemed insulin resistant to be allowed into the study).

I do find it interesting that they would include participants that supplemented with <25 mcg/daily, it is only recently it has been allowed in Norway to sell supplements with daily doses of >20 mcg. Norway has been very restrictive with vitamin D supplementation and worried about toxicity.