Q. My father was told he had low levels of vitamin D and that he should take a supplement. He read about vitamin D helping lots of problems, including diabetes, arthritis and the muscle pain from statin cholesterol-lowering drugs.
He began taking mega-doses of vitamin D and ended up almost in a coma with severe muscle damage. His calcium level when they evaluated him in the ER was 17.5 (normal is 8.6 to 10).
The doctors ruled out other reasons for elevated calcium and concluded he had vitamin D toxicity. It took five days of treatment in the hospital before he could walk well enough to go home. He is now almost back to normal.

A. Your father’s story really demonstrates the “Goldilocks” nature of this vitamin. Both too little and too much can be dangerous. The trick is to get the dose just right.
We recently discussed vitamin D with two of the country’s leading experts. They debated appropriate dosing, toxicity and the pros and cons of this vitamin. We are sending you a CD of our hour-long interview plus a copy of our 8-page Guide to Vitamin D Deficiency. In it, we discuss the many problems, such as joint pain, muscle strength, susceptibility to respiratory tract infections, high blood pressure, diabetes, osteoporosis, depression and asthma. We also describe the test to determine if vitamin D levels are too low, too high, or just right, as well appropriate supplementation.

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  1. mr

    I agree with previous comments that this Q&A was not helpful at all, and leaves one with a sense of frustration about how to get some worthwhile information.

  2. sbg

    I was recently prescribed vitamin D2 (50,000IU) even though I have been taking D3 for years. My D3 levels were fine, but the D2 was very low. I verified with another doctor that there is a difference in how these two forms of vitamin D work. 50,000 IU’s of D will be D2. I have yet to see D2 available without a prescription. There appears to be some disagreement as to which form one needs. However, I feel much better the day after my weekly maintenance dose of D2 so I would not call this a “junk” form of vitamin D in my case.

  3. Gigi

    When my moher was in her 80’s her bones in her ribs kept breaking. This caused it to pinch her lungs and was very painful. She had to have calcium shots daily. I’ve been taking Tums (walmarts brand) to keep my bones from breaking. My mother drank A LOT of milk and dairy products. She loved to garden and spent a lot of time in the sun.

  4. shell

    A friend of mine went to see an endocrinologist who specializes in bone health last year when she found out that she had very low bone density. They went over her diet and the amount of calcium that she got from food. She gets a lot, mostly from collards and bok choy and other vegetables, and she does not eat dairy. He approved, and told her to not take any supplemental calcium as it would likely end up as kidney stones since she’s getting so much from her diet as it is. He did tell her to take 3000 IU of vitamin d per day.
    She checked her bone density again a year later, and it had improved.
    So you don’t need dairy or calcium supplements. Just consume a lot of leafy greens!
    And vit d !

  5. s.h.

    I wanted to add some more about vit D-3 and blood calcium levels.
    A family friend has beginning osteo. For years, way before D became news worthy, she has been on at least 4,000 IU daily, as per her specialist. The day she told me about her larger doses of D-3, I asked her about how much calcium she took. She said, none, except an occasional very small dose like over the counter tablets have.
    Now, before I jumped to conclusions that her doc was a quack, she reminded me that he was a highly trained doctor and treated team players on a professional ball team in Tennessee. He is highly trained in orthopaedics and the medical school there lauds him.
    It seems that higher doses of D-3 is supposed (I heard and read), is supposed to scavenge calcium from organs and places it is NOT supposed to be and place it through the blood BACK into bone where it belongs.
    Perhaps folk have assumed that a body still needs huge doses of calcium while taking the higher doses of vitamin D!
    Also, I, along with many folks have a condition called hyper-parathyroid disease. For me, it was discovered during tsh thyroid tests, and because I had high calcium. I was on 5000Iu daily of D. When my family doc saw the high levels of para-thyroid hormone in my blood, he stopped my calcium and allowed me to continue the vitamin D-3. After a few months, levels became more normal. With out the osteo drugs out there. If I am not normal completely at my next blood test I might have my para-thyroids checked for benign tumors.

  6. LP

    I was told by my DR. to take 5000IU in the morning, then 5000 in the evening, I still do not know if this dosage is ok?

  7. Karen

    +1 to other posters who identified that lack of real data in this post makes the content close to useless.
    D2 can easily be overdosed, D3 less so. “Almost” in a coma? What’s that? There’s a clear 15-point coma scale; if there’s no number, there’s no meaning to the phrase.

  8. Marsha

    I was diagnosed as deficient with a score of about 30 so I was put on 50,000 IU for once a week for a few months and rechecked. There was no change so they increased the dose to twice a week for awhile and retested. No change so at the end of December I was put on 50,000 IU three times weekly. I was a compliant patient and took my medications as instructed. I just got checked and my blood level is 137+. They left a message for me to quit taking the D2 and then I got a prescription in the mail to have my blood checked in one month. I am very worried and can not find out just where toxicity begins. I am 5’1 at 120bls. Does this make a difference?

  9. DS

    I would like to know more about drug interactions with Vitamin D. I take 5K a day and sometimes double that, and have not experienced my usual February illness for two years now.

  10. KH

    I thank you for the information; however, I was not able to give it the full five points because your response did not identify which Vitamin D this information referenced. Was the information only about Vitamin D, or was it for all of the Vitamin D’s, i.e., Vitamin D2 and/or Vitamin 3, or does it make a difference which one it is? Does the information you provided cover all of the categories of the Vitamin D family? I only take Vitamin D3, so I would like your take on the safe dosages of Vitamin D3 if it is not the same as Vitamin D alone. Thank you.

  11. ECC

    I agree with the other comments here – without knowing what the writer describes as a “mega-dose” it’s hard to effectively blame just “Vitamin D” as there’s no mention of whether it was Vitamin D2, Vitamin D3 or whatever.

  12. Katherine

    I’ve been on thyroid replacement for thirty years (level checked annually) but in the last ten I had less and less energy. My Vitamin D level was checked four years ago and was extremely low despite that I am out in the sun a good part of the day. Vitamin D (now taking 1200 units per day) has given me sufficient energy for my age as well as taken away 50% or more of the aches and pain (osteoarthritis) I previously experienced.

  13. s h

    I was found to have high blood calcium. I took 1000 mg of calciums a day and 5000 IU of D 3 not junky D2. I have worked in an office without windows since the early 1990’s and got little sun. When my Dr did blood tests for calcium levels he also did one for my thyroid and especially ParaThyroid levels. They were 86. My ParaThyroid level was way outta kilter. -he is keeping a watch on those levels because I could not afford ParaThyroid surgery, anyway, right now.- I was taken off ALL calcium supplements, dairy and food with calcium. I continues my 5000 IU daily of D-3.
    I still work in a room without windows and no sunlight and get my D from supplements. My dr is pleased that my Parathyroid and calcium levels are almost to normal. NOW my muscles work pretty well but they still seem a little stiff. Sometimes, but they are almost normal, now!I would check for parathyroid problems before blaming D-3 or worse:D-2.

  14. LP

    I was told to start using Vitamin D. I was told to use 5000 mg, twice a day, is this too much?

  15. michaeldarianjensvold

    Without any mention of the Vitamin D dose or duration, neither by the letter writer nor in your response, this Q & A is little more than anti-vitamin D fear-mongering. It stands in stark contrast to the detailed information (source, footnoted) about dosage and effects provided by groups like the Vitamin D Council.

  16. Scott

    So, what dose was he taking? My understanding is for most men 2000-4000 IU’s daily is safe. Some say much higher doses. Women less, but still around that 2000 number. As a rule, at what level of intake would one maybe stretching it?

  17. Chris

    I think this piece underlines what has become clear from your programme for some time.
    It seems as if research is performed, or new drugs or procedures introduced, and suddenly a particular treatment is seen as a panacea and we should be trying to get as much of it as possible.
    In addition to Vitamin D – which I read elsewhere about a year ago had “no upper limit” for intake (!) – there are many examples of this, some being:
    # statins (you mentioned them in the last programme)
    # screenings (prostate and breast)
    # stents
    The truth is probably that we should all (patients and clinicians) wait some time while all the implications of a treatment are worked out before embarking on recommendations for the general population.
    Of course how long that period of time should be is the moot point.

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