Too much vitamin D is not good for you

ProfG has been urging people to ensure that you are vitamin sufficient.

He recommends the dose advised by the Vitamin D Council

This will maintain bone health and maybe, just maybe it will impact on your MS.

However some people have gone overboard and have found that to much of a good thing is bad.

Here is the case of an individual who was taking 10 times the vitamin D council dose.

Feige J, Salmhofer H, Hecker C, Kunz AB, Franzen M, Moré E, Sellner J Life-threatening vitamin D intoxication due to intake of ultra-high doses in multiple sclerosis: A note of caution. Mult Scler. 2018 Oct 25:1352458518807059

Knowledge about complications of chronic ultra-high dose vitamin D supplementation is limited. We report a patient with primary progressive multiple sclerosis (MS) who presented with generalized weakness caused by hypercalcemia after uncontrolled intake of more than 50,000 IU of cholecalciferol per day over several months. Various treatment strategies were required to achieve normocalcemia. However, renal function improved only partly and further progression of MS was observed. We conclude that patients need to be informed about the risks of uncontrolled vitamin D intake and neurologists need to be alert of biochemical alterations and symptoms of vitamin D toxicity.

We know that Vitamin D (Cholecalciferol = Vitamin D3) and too much calcium don,t mix and this person had problems associated with too much calcification.

Dr Ruth has given words of wisdom on this but until is is visible I can’t say what, so take these in moderation there is no solid evidence that it will impact your MS to any large extent and I would suspect that it will not based on the view that the immune response that deals with infection is not irradicated by Vitamin D supplementation

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  • 50k/day is a lot, is it too much? I don't know, perhaps 10k/day is enough. However, we should take a similar approach to side effects on drugs. No drug comes without side effects, I would say side effects are the norm, such as PML with Natalizumab, Infections with the other antibodies, or even cancer. The fact that there are only few reports on Vit-D toxicity tells me that it is on the save side of things…

    • With Vitamin D3 you have to look at the blood levels: calcium and PTH. The calcium level must be within the reference range. It is not an expensive test.

  • It is possible to take more than vitamin D3 10 000 IU/day in combination with a calcium free diet. It is called the Coimbra protocol. Hundreds of People with MS are following this protocol world wide. Speciallized doctors all over the world are prescribing this protocol. The vitamin D3 dose is individually adjusted on the basis of the PTH.

    It is a shame that the above mentioned paper is not free of charge for PwMS.

    • It would be good if there were proper trials of the Coimbra protocol for pwMS. Many wonder why this has not been done so far and results published.

    • What does this calcium-free diet do to bone and teeth health? MS or no – ending up with osteoporosis resulting in e.g. spinal or pelvic fractures and a poor set of teeth isn't going to do a person any good.

  • The toxic dose is known to occur at about 40,000IU for about 6 months. Below this level vitamin d is a food and above this it is a drug. Life guards who spend their time in the midday sun appear to make about 10,000IU a day of vitamin d, so the body seems to have spare functional capacity. The vitamin d as taken is converted into 25(OH)D and bound to vitamin d binding protein. This then travels round the body in the blood until required. When required cells convert the 25(OH)D to the active hormone 1,25(OH)D as needed. So long as the intake does not overload this storage and transport system the control system works correctly, and there are no side effects. Thus it is food, as the vitamin d is being used under the control of the body using the system evolved for it to work.

    If you exceed the storage capacity the 25(OH)D is no longer bound and now is free to have effects on the body via different mechanisms. It is not being converted to 1,25(OH)D as 1,25(OH)D is suppressed by high 25(OH)D. It is now acting directly as a drug. If you are going to use it as a drug then calcium intake will need to be restricted.

    That said you do get hypercalcemia in people with normal or low vitamin d (25(OH)D levels.

  • Conclusion: These findings highlight excessive vitamin D supplementation and resulting hypercalcemia as novel risk factors promoting worsening of CNS demyelinating disease. Our data caution that in light of the currently limited information on a direct beneficial effect of vitamin D in MS, MS patients may be at danger of experiencing untoward immunological and/or clinical effects when vitamin D is supplemented excessively.


    • Vitamin d is used as a rat poison because rats are very sensitive to high vitamin d levels. So what the papers say is that rat poison is bad for rats. The only know toxic effect of excess 25(OH)D is high blood and urine calcium levels and it is the high blood calcium that is the problem not the vitamin d. If the vitamin d level is not high enough to disrupt blood calcium levels there is no problem. You will know if your blood calcium levels are wrong because you will be quite ill.

    • Sorry about the tone of my previous comment but I find this type of presentation of work irritating. They have a throwaway comment that higher levels of vitamin d without hypercalcemia appear to have a positive effect, before concentrating on the negative effects of overdose. They quote a 25(OH)D blood level that is known to be toxic in rats but not people, but do not explain that the toxic levels are different. They concentrate on the vitamin d as the cause rather than that they have induced hypercalcemia, which is the actual problem. I guess 'Vitamin d in Moderation is Good for You' would not attract many citations.

  • I'm sure I read that body size and weight should be considered with Vitamin D dosage. If you're larger the more you need and smaller the less you need.

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