Is Vitamin D Toxic?

For more by Dr. Jonny Bowden, we recommend The Truth About Gluten.

Q: Can vitamin D be toxic?

While it’s possible, vitamin D toxicity is about as common as a three-legged cow.

The issue got a lot of press recently when alternative health guru Gary Null, PhD, became deathly sick, apparently from taking “too much” vitamin D. (The case was especially strange because the offending product was one of his own supplements, “Ultimate Power Meal.”)

The product was labeled as containing 2,000 IUs (international units) of vitamin D per serving (the supplement was a powder form). The actual amount per serving was – wait for it – two million IUs per powdered serving. Null consumed this amount for three straight months. He recovered within a few months of stopping the supplement and has since sued the manufacturer.

According to the very conservative Institute of Medicine of the National Academies, the “tolerable upper limit” for vitamin D intake is 2,000 IUs a day.

While I can tell you that I personally take 10,000 IUs of vitamin D each day, I can’t recommend more than 2,000 IUs because that’s the amount that has been vetted in research, even for children who are over the age of one.

Let’s keep in mind that Null was taking two million IUs a day – exactly 1,000 times the recommended dose.

So can excess vitamin D be toxic? Sure,just as too much water or oxygen can be toxic, but realistically, you’re much more likely to be getting too little than too much.

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