STUDY: Vitamin D Lessens the Severity of Restless Legs

[CalmLegsJL]

The name of this 2014 study lead by Doctor Siraj Wali is called

"THE EFFECT OF VITAMIN D SUPPLEMENTS ON THE SEVERITY OF RESTLESS LEGS SYNDROME"

Results: "The median RLS severity score improved significantly."

Conclusion: "This study indicates that vitamin D supplementation lessens the severity of RLS symptoms."

https://pubmed.ncbi.nlm.nih.gov/25148866

[Polar Bear]

I note that the 12 subjects in the study were all Vitamin D deficient prior to the treatment.

i.e. ""Vitamin D supplementation lessens the severity of RLS symptoms where Vitamin D is deficient""

[Rustsmith]

Vitamin D deficiency can cause a wide range of neurological problems. My neurologist regularly checks my Vitamin D and B12 levels even though she knows that I take them daily.

[CalmLegsJL]

There are two other similar studies. The first is by the same researcher.

Both studies connect RLS with Vitamin D deficiency. It doesn't mean that everyone with RLS is going to have Vitamin D deficiency, but it's clearly more prevalent in RLS sufferers.

THE ASSOCIATION BETWEEN VITAMIN D LEVEL AND RESTLESS LEGS SYNDROME: A POPULATION-BASED CASE-CONTROL STUDY
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5886433

CONCLUSION
Our study identified an association between vitamin D deficiency and RLS. Consequently, vitamin D deficiency should be considered in the management of RLS.

ANALYSIS OF SERUM VITAMIN D LEVEL AND RELATED FACTORS IN PATIENTS WITH RESTLESS LEGS SYNDROME
https://www.frontiersin.org/journals/ne ... 82565/full

CONCLUSION
The serum VitD level is generally lower in patients with RLS than in healthy people, and lower serum VitD level is associated with more severe symptoms of RLS, worse quality of sleep, and worse depression.

[Frunobulax]

Our study identified an association between vitamin D deficiency and RLS. Consequently, vitamin D deficiency should be considered in the management of RLS.
[...]

The serum VitD level is generally lower in patients with RLS than in healthy people, and lower serum VitD level is associated with more severe symptoms of RLS, worse quality of sleep, and worse depression.

Association and correlations do not mean causation, even if a LOT of studies imply this (wrongly). Belt size is strongly associated with obesity. Doesn't mean that the large belts are causative for the obesity.

Vitamin D is an antioxidant that will be consumed in a large number of inflammatory conditions. As chronic inflammation is suspected as a cause of RLS, it is not at all surprising that vitD is be lower in RLS patients. But does RLS improve, significantly, long term, under vitamin D supplementation? For which subgroup of RLS patients?

[RestlessNan]

Was deficient in Vit D for many years. This became a concern when I became osteopenic in menapausal years, so calcium and Vit D. were increased and I was even mega-dosed with Vit D for several doses. Now I maintain with taking 5,000 units/day of cholecalciferol. There was no thought of restless legs while I corrected this deficiency, nor has it seemed to help to have a more than adequate level for these years that the RLS worsened. Another aspect, and I don't know how to relate it except coincidence. There is a higher incidence of RLS in northern European countries, as there is a high incidence of Vitamin D deficiency in the same countries probably due to the lack of sunlight for such a long period of time each year. It may impact a study if participants were of this background. I don't know if it was mentioned but the Vitamin in Vitamin D is a misnomer, as it is actually a hormone. If one is taking large amounts without knowing their numbers, they may be taking in too much as it is fat soluable and can be stored instead of excreted like water soluable supplements. I don't have references for these statements, they're in my head.

[Rustsmith]

Nan, thanks for bringing up the risk associated with taking too much Vitamin D. There was recently a new item about a man in the UK who died after taking mega doses of Vitamin D for many months. Apparently he fell into the trap of thinking that if a little bit is good, more is better.

Just like iron, too much can be harmful. The same is true of some other fat soluble vitamins. Therefore, if you think that you have a vitamin D deficiency, ask your doctor to include that in your next blood test. If you are in the normal range, don't take more than the FDA recommended daily dose.

[Frunobulax]

True, too high doses are dangerous. Unfortunately we don't really know where the cutoff is. There are only case reports, to my knowledge there isn't a single study linking high vitamin D intake with negative effects. And a lot of these cases are, um, a bit of a stretch. I remember researching cases of vitamin D overdosing, and found wild stories. There was a man who had t2 diabetes, high blood pressure and whatnot, took 5 different drugs. He went on a 3-week vacation on Thailand and was hospitalized something (I think hypercalcemia) when he came back. Docters were 100% sure that the vitamin D and only the vitamin D was to blame because he was in the sun too much. Jesus wept.

There are arguments that both the "normal range" is too low. The reasoning is that the normal values are what are observed in healthy people, but they too come from a background of not going out in the sun and using high level sunscreen. Some agencies recommend doses of 400IE per day, which is just enough to prevent rickets -- but there is no evidence that this leads to an optimal vitamin D status (however we might define that).

Our body makes about 20.000 IE of vitamin D if we're out in a sunny day, if we don't get sunburnt. So I'd argue that 400IE is way too low, probably. And just recently there was a mid-term study using up to 50.000 IE per day (https://www.sciencedirect.com/science/a ... 6018306228) which appeared to be safe and have positve effects.

My strategy is to achieve a vitD level around or slightly over the normal range, which I achieve by sunbathing as often as possible (living in a cold-climate area, I can do this only 4 months a year or so) and taking 10.000IE per day. But it's all based on conjecture, and I can't be sure that I'm doing the right thing.