What Happens if You Take Too Much Vitamin D?
The main consequence of vitamin D toxicity is hypercalcemia, which means that there is too much calcium in your blood. The symptoms of this are:
- Nausea and/or vomiting
- Irritability and/or confusion
- Constipation
- Fatigue
- Decreased appetite
- Weakness
- Kidney stones
The Bottom Line
Vitamin D supplementation might be a good idea for some of us – maybe our levels are too low and some research indicates that people with MS metabolize vitamin D differently, so have a hard time keeping levels up. I actually got my vitamin D levels checked after reading some of these comments and was surprised when it came back within the normal range, as I was convinced that I was deficient (and hoping for some of the fabulous reported benefits from fixing this deficiency with supplementation). It's worth looking into, I think, as the solution is pretty easy.
However, I'll repeat it -- if you are interested in vitamin D supplementation at anything above a level of 1000 to 2000 IU/day, you need to mention this to your doc (neuro or general practicioner) and work with him or her. Different doctors have different approaches to supplementation. I have heard of some who "frontload" huge doses, then maintain with more conventional dosages. Others build up levels gradually. Having a health professional monitor blood levels and dosages will allow you to adjust your supplementation strategy.
Sources:
Hathcock JN, Shao A, Vieth R and Heaney R. Risk assessment for vitamin D. American Journal of Clinical Nutrition, Vol. 85, No. 1, 6-18, January 2007.
Heaney RP. Vitamin D: criteria for safety and efficacy. Nutr Rev. 2008 Oct;66(10 Suppl 2):S178-81.
UpToDate. Vitamin D: Natural drug information. Accessed November 2010.
MedlinePlus. Vitamin D.
