Tired of the battle of the experts? Imagine how the experts feel! In this article, I not only report on the science of vitamin D and pain, but describe my own struggle to decide what to recommend to my readers, before and after the impact of some official vitamin D recommendations from the Institute of Medicine in late 2010. (You can also skip to the punchline.) Readers genuinely concerned about the safety and accuracy of Vitamin D supplementation may find the thought process to be quite helpful.
I am getting ready to dive into a pile of Vitamin D science. I can’t begin to master it myself, and so I will rely heavily on two mentors — opinions that will almost certainly conflict. One is Dr. Tim Taylor, who authored a critical chapter of my own muscle pain book. The other is Dr. Harriet Hall, retired Air Force surgeon and weekly Science-Based Medicine contributor.
Dr. Hall’s article on Vitamin D is sitting in my inbox right now, waiting for editorial attention. So are a stack of citations from Dr. Taylor. What am I going to think about Vitamin D at this time on Monday?
My position to date is that D deficiency is:
I haven’t held this position with any passion, and if challenged on the science I would admit I have been on scientific terra not-so-firma. I was taking Dr. Taylor’s word for it, basically. In the chapter he contributed to my triggers points book, Dr. Taylor recommended high doses of Vitamin D for deficient patients, and also set the threshold for deficiency lower than most official sources. Dr. Taylor defended those recommendations with some citations that seemed good enough to me at the time — good enough to publish, anyway. I cautiously took a pro-D position myself.
And then on November 30 the Institute of Medicine published a report strongly criticizing over-prescription of Vitamin D and generally sneering at the idea that deficiency is common.
“Uh oh,” I thought, when these headlines arrived in my inbox.
A flurry of emails with Dr. Taylor resulted in some immediate corrections to the book. (Dr. Taylor had already revised his own recommendations for Vitamin D — still high, but a lot less high.) We then continued the discussion, agreeing that we needed more substantiating evidence to support even the reduced recommendations in the book.
Meanwhile, Harriet Hall agreed to take on this topic for her her Dec 7 post at ScienceBasedMedicine.org — which is waiting for my editorial attention as I write this. And I’m quite concerned that my recommendations will be slammed too.
It’s 7:45am, the cat wants me to stop typing so she can sit on my lap. I have a new Kindle I want to try out, and three good books on the go. My wife will be awake soon, and we’ll probably go out for our favourite eggs benedict. I have chores, errands, and social events throughout the weekend. But instead I’m going to sit here and try to figure out what to say about Vitamin D by Monday!
I enjoy confessions and corrections of wrongness (they are cleansing for the soul, not to mention popular). Alas, I just don’t seem to have any wrongness about vitamin D to confess or correct — not today, not yet. Examining the evidence this weekend caused no earthquakes. This was a false alarm — it did give me an opportunity to really firm up my own opinion.
Same as before. The new guidelines simply have almost nothing to do with the recommendations for D supplementation that I make.
The Walmart shopper looking at a sale on 5000IU vitamin D capsules is a completely different critter than the chronic pain patient wondering if, perhaps, their vitamin D deficiency could be a factor in their horrible problem. Is the average person deficient? Do they need 5000 IU per day? Probably not. That is what the IoM guidelines are concerned with.
But the pain patient might. The geometry of risk and benefit is completely different for pain patients. If you are a “hurtin’ unit” — as a colleague of mine puts it — vitamin D is worth thinking about.
I know some readers are reading this my perspective on the value of vitamin D in general, but I’m not going there. Read Dr. Hall’s post for that. My job here is much simpler and more focussed on the D-for-pain question.
Answer: probably, yes. There is a fair bit of evidence showing a correlation between low D and musculoskeletal pain. The correlation might not mean anything — but there’s a good chance that it does. And while there is absolutely no evidence that supplementing with D will help pain, it is plausible. And the new IoM guidelines basically had absolutely nothing to at all to say about the pain connection. Ships passing in the night.
What if you are deficient, or borderline? Is it safe and sensible to take higher dosages of vitamin D temporarily to correct to the deficiency? Answer: yes, it’s definitely safe, and probably worthwhile.
The only thing I really scrambled to check carefully this weekend was the safety of higher dosages. Ethically, the idea of erroneously recommending a useless treatment just makes my head explode. If I found that my name is on an unsafe recommendation … well, it doesn’t bear thinking about it …
Again: probably, yes.
The IoM set an upper limit of 4000 IU as a safe average maximum that anyone should be taking — a little less than the popular 5000 IU pills now available.
However, there is a wide margin of error here. There is no question that excessive vitamin D can be dangerous, nor any question it takes a lot. Indeed, megadoses of 50,000 IU/day have failed to produce any sign of toxicity, and when supplement baron Gary Null overdosed on vitamin D in his own contaminated product — talk about poetic justice — he was taking upwards of two million IU per day. That nearly killed him, but it didn’t, and we’re talking about a dose five hundred times larger than the IoM’s upper limit — such a ridiculous number that I’m really only bringing it up as a fun example. Here’s a summary of the recent evidence from Heaney:
Both the intoxication literature and the recent controlled dosing studies have been reanalyzed by Hathcock et al. These authors show that essentially no cases of confirmed intoxication have been reported at serum 25(OH)D levels below 500 nmol/L. Correspondingly, the oral intakes needed to produce such levels are in excess of 20,000 IU/day in otherwise healthy adults and, more usually, above 50,000 IU/day. These findings led Hathcock et al to select 10,000 IU/day as the tolerable upper intake level (TUIL, or UL), with considerable confidence.
I also discussed the toxicity issue briefly with Dr. Hall. She agreed that anything under 50,000 IU is unlikely to be toxic (and again that would be especially true for temporary supplementation for deficient patients).
Mission accomplished: my job was to make sure that it still makes some sense for pain patients to consider D deficiency and that it’s safe to supplement fairly generously, and it does.
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.
Dr. Stewart Leavitt of pain-topics.org has watched the topic of vitamin D for pain closely, and written about it extensively, and he responded to the new IoM guidelines just as I did: by re-examining his position in this clear, readable article, New IOM Report Snubs Vitamin D Research. His report is much more authoritative than mine, and comes to similar conclusions. The IoM report actually “neither confirms nor refutes our prior research and advocacy for vitamin D supplementation as benefitting pain relief, particularly relating to musculoskeletal disorders” and “we do not believe it is necessary or appropriate at this time to recant our prior positions regarding vitamin D for pain.”