Heart palpitations as a result of vitamin K2 supplementation and whether increasing calcium intake could help | Masterjohn Q&A Files #13

Question: “Vitamin K2, MK-4 and MK-7, might have caused prolonged heart palpitations. Upon stopping it, symptoms mostly resolved after a week or so. Does that mean that the body is better off without it? Might increasing calcium intake mitigate this?” 

I would say, the calcium is really interesting. I genuinely hadn't thought of that until you mentioned it. Even though I've heard other people ask this question, I haven't had time to look into it, but you raise a good point.

So, it is conceivable, for example, that your bone density has been very low because you have not had the K2 you needed to get the minerals into the bone. So when you get the K2, you start loading the calcium into the bone, but maybe because your whole body is programmed to assume things were the way they were before you started taking the K2, then it doesn't adapt fast enough to normalize your blood calcium, which, by the way, how do you normalize your blood calcium? You take calcium out of the bone.

MK-4 has been studied in high-milligram doses as an osteoporosis drug because it inhibits bone resorption. If you inhibit bone resorption, you will definitely interfere with your ability to maintain normal serum calcium levels because bone resorption is how you do that.

So, either you're giving the nutrients needed to get the calcium into the bone and the body is just prioritizing that because it's been missing them for so long, and your serum calcium drops — or you're actually creating signaling stopping bone resorption, and so your blood calcium drops because of that.

Either way; taking calcium might impact that, and I would love to have some anecdotal data on that because there's no studies on K2and heart palpitations. So, I would love it if we have some anecdotes of people saying whether the calcium helps, especially since so much of the K2 stuff is so skeptical of calcium. 

Kate Rheaume-Bleue's book Vitamin K2 and the Calcium Paradox, I think it's a great book. Basically, what that book is, is an enormous elaboration of my 2007 article on Activator X and Weston Price. 

If I had written that book, I would have done things a little bit differently. The whole idea of the calcium paradox that's in the title, I think it has merit. There is some data indicating that calcium supplements might worsen the risk of heart disease, but I think that the conclusions are way too anti-calcium, and I think there's too many people out there taking K2 who have it in their heads that calcium supplements are bad. 

Calcium supplements are bad compared to getting enough calcium from food. A huge portion of those people are not getting enough calcium from food, and getting calcium is more important than where it comes from.

This Q&A can also be found as part of a much longer episode, here:https://chrismasterjohnphd.com/podcast/2019/02/09/ask-anything-nutrition-feb-1-2019/ 

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  1. I’ve struggled with lowish bone density most of my life, which as a child manifested as mild rickets (I have bowed legs) and frequent respiratory/ear/throat infections. In adulthood it showed up as occasional bouts of painful fairly disabling osteomalacia. There were also other symptoms which I now know were typical of Vitamin D deficiency. I now manage things fairly well with regular large doses of Vitamin D3, some Vitamin A (retinol) plus supplements of calcium, magnesium and others. I have tried using vitamin K2, as MK-4, MK-7 MK-9, in various doses either singly or in different combinations, but with little success. Unless I use an almost insignificant K2 dose I start to suffer with low serum/soft tissue calcium after a few days. The symptoms are always the same and manifest as general weakness, muscle pain, insomnia, loose stools, palpitations, back pain, toe & hand parathesias and tetany type leg cramps, particularly in the upper calf muscles. 3 gm (600 mg calcium) doses of calcium citrate, several times a day, will get rid of the worst symptoms over a day or so. I no longer risk using Vitamin K2. I now suspect I have some type of hypoparathyroidism and/or Vitamin D genetic polymorphism and need regular high doses of Vitamin D3 and calcium. When measured my serum calcium is always in the normal range and the Vitamin D is high usually over 100 ng/ml. Over the years doctors have never picked up this Vitamin D problem and I was usually told I had arthritis or similar. As the affliction is now quite well managed, I suspect further investigation is likely not worthwhile.

  2. I’ve seen several K2 supplements with calcium (specifically
    calcium phosphate or dicalcium phosphate) as the delivery

    With the calcium component being 99% of the product and K2
    the 1%. example (99mg dicalcium phosphate to 1mg K2 (Mk-4))

    If trying to remove calcium from the body (for arterial health purposes, not bone) isn’t this a counter-intuitive supplementation?

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