Does vitamin D treat pain? Unknown! Maybe? ∞

We know that vitamin D deficiency and pain are probably related — see above — but that doesn’t necessarily mean that taking vitamin D is going to actually help the pain. There’s almost certainly not a benefit for any kind of pain patient, which is hardly surprising — there are many different kinds of pain, and it would be shocking if vitamin D was good for all or even most of them — and a pair of recent reviews both show this clearly (see Straube 2015, Wu 2016). (Although one of them did actually detect a slight benefit. Just sayin’!) Both reviews mainly just expose the sad state of the evidence regarding the specific kinds of chronic pain that might be more likely to benefit, such as fibromyalgia. The only studies of treating that condition with vitamin D are actually quite clearly positive (see Schreuder 2012, Wepner 2014).

But “more study needed” in a big way! Beyond these scraps of evidence, for now there is only educated guessing and clinical experience.

Nothing’s ever simple and chronic pain least of all: it’s usually caused by a sinister stew of factors that eat away at people for many years. Trying to solve the problem by fixing one thing — if indeed vitamin D is even a problem — may be about as feasible as trying to fix a broken engine with just one tool. Vitamin D deficiency may contribute to a chronic pain disaster over time, but by the time you’re actually in trouble the problem may be much more complicated than just vitamin D deficiency.

That’s a bleak warning not to put too much hope into vitamin D. But there are still reasons for optimism! And the only thing worse than chronic pain with six causes is … seven causes. Obviously. Anything you can do to simplify the pain equation is a good idea, and you can certainly take vitamin D. (Just consult with a doctor first, please.) It’s cheap, safe, and effective, so it’s an ideal candidate for presumptive treatment: going ahead and treating based on the presumption of vitamin D deficiency even if it has not been established with blood tests. By all means do that too, of course! But if a lot of healthy people take this stuff “just in case,” it’s hardly radical for pain patients to give it a shot.

This is an excerpt from a recent major update to my vitamin D article. For more information see: