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Human Study Suggests Vitamin K2 (as MK-7) REVERSES Arterial Calcification

This is an exciting post since there is some amazing new data on vitamin K2 in the form of MK-7. I don't believe this has yet been published in a peer-reviewed journal (so there is no reference below as usual), but once it gets published, I'll be sure to cover it again or link back the reference.

[Update: click HERE for the post with this study's published reference.]

At the Vitafoods convention in Geneva, taking place as I write this, Dr. Cees Vermeer, at VitaK laboratory (of Maastricht University), presented new data showing significant benefits for improved bone strength and prevention of cardiovascular aging with daily supplementation of natural MK-7.

In the study, 244 healthy postmenopausal women received 180 µg of MK-7 daily, or placebo, for 3 years. The clinical endpoints included bone mineral density, bone strength, and vascular characteristics measured by ultrasound and pulse-wave velocity (PWV, which evaluates age-related stiffening of blood vessels).

After at least 2 years, the bone-related benefits of MK-7 supplementation included a statistically significant protection of the most vulnerable bone structures (vertebrae and the hip), and a clinically relevant improvement at the site of the femoral neck.

With respect to the cardiovascular benefits, the study showed substantial benefits in preventing age-related stiffening of arteries in the MK-7 group, while the placebo group saw an increase in the PWV.

However, the most amazing finding was that "nutritional doses" of MK-7 not only prevented stiffening, it also resulted in an unprecedented statistically significant improvement of blood vessel elasticity both measured with ultrasound and PWV. Of course, based on the mechanism of vitamin K's activity, this implies that pre-existing calcification in the arteries was reversed (although it would have been icing on the cake, if the study actually measured the calcium content in the blood vessels).

Previously, the benefits of vitamin K on bone and vascular health had been demonstrated with "pharmacological doses" of synthetic forms of vitamin K (as MK-4) of up to 45 mg daily (note 1 mg = 1000 µg). Remarkably, the effects of MK-7 at 180 µg/day were even more pronounced than those in trials using a high dose of one of the synthetic forms of vitamin K.

Now, I'm not sure if you understand the profoundity of this study (...and before you say, "profoundity is not even a word"...it is now...I just made it up), so let me explain. Recent evidence suggests that the loss in elasticity of the arteries caused by calcium deposits in the arterial wall (called arterial calcification) is the #1 predictor of a cardiovascular "event" (like heart attack or stroke). The results of this study show that we can not only prevent this from happening (which we already knew from previous studies), but we can actually REVERSE it (previously only seen in an animal study)!!!

This means we now have human evidence to show that simple daily MK-7 supplementation can reverse the #1 predictor of heart attacks and strokes! So take your vitamin K, now. Go!

BTW--if you haven't already--isn't it about time you subscribe to Know Guff?

Source: Presentation at VitaFoods, Geneva, Switzerland, May 22, 2012.

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  1. How would I get 180 mcg from my diet? What are good sources?

  2. Well, I know the researchers say "nutritional doses" but I think they were just saying that to compare to the pharmacological doses used with the other form of K2 available in supplemental form, MK-4. Personally, I feel that unless you're eating natto (a fermented soy dish from Japan), it'll be rather difficult to get this amount just from diet. Perhaps it was possible in the past when we ate more rich sources of vitamin K, but today's culinary options don't give us many good sources.

    Personally, I take supplemental MK-7 daily as well as my whole family. I don't take a lot of things daily, but K2 is one of them.

  3. Speaking of calcium. A friend has calcium build-up/deposits (not sure what the right term is) in her toes.
    I know she takes a calcium supplement (she's menopausal) that she buys at the compounding pharmacy (made on site).
    Is taking calcium and having calcium build-up related? I fwded her one of your blog about K2 and calcium and she's thinking about taking K2.
    Any thoughts?

    1. For sure A lack of vitamin K will allow calcium to be deposited in many more areas than just the arteries, although this is what's getting most of the attention now. There are, I think, about 16 vitamin K-dependent proteins in the body. For example, in this post, I discuss how vitamin K could help prevent kidney stones.

      If she's taking calcium (or even if she's not), I think the evidence is strong enough now that there shouldn't be any question as to whether you should take vitamin K2...it's a resounding YES! She needs supplemental K2.

  4. Do you need to split this dose into smaller doses throughout the day, or can you take it all at once?

    1. When using the MK-7 form of vitamin K2, you can take the full daily dose all at once (of course, very large doses would probably be best split up, but 180 mcg/day isn't extremely large, IMO).

      This is because MK-7 has a very long biological half-life compared to K1 or MK-4 (other forms of vitamin K you'll find as supplements), which both have a half-life of about 1-2 hours (so you'll want to take the daily dose for these forms in divided doses throughout the day).

  5. The investigators found that Mk4 strongly activates transcription of two specific genes in osteoblast cells. The genes are GDF15 and STC2 and they’re involved in bone and cartilage formation.
    !!!Their results show that Mk7 did not activate these genes.!!!

    Pls see the Journal of Molecular Endocrinology

    1. Great reference! Makes a lot of sense too.

      While I'm not an expert in the biochemistry of menaquinones, with my limited understanding, I'm under the impression that MK-4 is actually the "active" form of K2 humans.

      MK-7 is great and has amazing therapeutic potential, but I believe the body must convert it to MK-4 for it to be used. You should think of MK-7 more as a storage form. (Don't quote me on this--and hopefully, some one more knowledgeable than I can add to this discussion.)

      Drawing parallels to vitamin D, MK-7 would be like 25-hydroxyvitamin D (the inactive storage form), which is then converted as needed to MK-4 (like how 25-hydroxyvitamin D is converted to the active form of 1,25-dihydroxyvitamin D in a tightly regulated process). The goal of vitamin D supplementation is to raise levels of the inactive storage form, not the active form (which in the case of vitamin D, may not be so desirable).

      This is why the in vitro (test tube) study referred to didn't show any effect from MK-7, and why it's always inappropriate (and sometimes dangerous) to extrapolate results from in vitro studies to a living organism, especially one as complex as humans.

      It'd be interesting to see if oral administration of MK-7 in a human would or could activate these same genes in vivo (through conversion to MK-4).

      Very interesting stuff though! ...and more questions than answers for the vitamin K researchers to work on. :)

    2. Quote:
      "It'd be interesting to see if oral administration of MK-7 in a human would or could activate these same genes in vivo (through conversion to MK-4)."

      I think the fact that the VitaK study in humans saw improvements in bone parameters would is proof that MK7 does activate these bone genes being discussed. If you're right about MK4 being the active form, then more proof that MK7 converts to MK4.

  6. what effects if any would come of combining vitamin K2-MK7 with Vitamin D and A?
    from other internet "evidence" - k2 effectively targets where vitamin D will go, rather than letting it float aimlessly through the cardiovascular system.

    ps - profundity is a word. the one you were looking for.

    1. That's agood question, but I don't have a good answer. However, keep in mind that, in nutrition, everything works best when taken together. This is why, from a prevention point-of-view, eating fish is better than taking fish oil supplements; drinking wine is better than resveratrol supplements, etc.

      From a treatment point-of-view, where we use single nutrients as therapy, you just need to know what potential side-effects can arise from unbalanced high-dosees of single nutrients...after all, with this approach, we're using supplements as drugs, so they should be treated as such.

      So while taking A and D would make sense, I'm sure it's far from the full-picture as further research will eventually show.

  7. if vitamin k2 reverses calcification where does the calcification go?

    1. That's a good question, and while I can't say with absolute certainty, logically, it would end up in the bones.

      Why? Because by consuming K2 (and I'm specifically referring to MK-7), you'll be activating numerous vitamin K-dependent proteins in the body. While MGP in the arteries will be activated and may help remove pre-existing calcification--according to the preliminary results discussed in this post--it will also activate osteocalcin, which is found in the bones. Essentially, what you're doing is just ensuring that calcium goes where it's suppose to go, and studies suggest that this is what happens.

      Unfortunately, unless we radioactively label the calcium in the arteries and then trace its path upon use of MK-7, we can't say with 100% certainty that this happens.

  8. Hi, you are writing about calcification of arteries. Then again more general about calcification in blood vessels. What about calcification in veins? Can Vitamin K2 reverse those as well? Is it the same mechanism/effect in the veins that causes calcification in the arteries?
    Do you know what the dosage is to reverse calcification in arteries?
    What happens if you 'overdose' on Vit K2? Is that possible?

    1. Hi Kath,

      Yes, the mechanism is the same. I guess a more appropriate term to use would be "vascular calcification," which seems to becoming more common. This would include both arteries and veins, but when studies look a vascular calcification, they typically measure calcium content in the arteries.

      As for reversal, this study (with these results) has yet to be published in a peer-reviewed journal. It's been almost two years now since these preliminary results were presented at the Geneva conference, so either I missed the publication, or perhaps the final results were not exactly what these preliminary results suggested. However, published human studies do show a slowing of the calcification process with sufficient K2, and at least one animal study did see a reversal. Here is a more recent published study...
      Vitamin K2 slows progression of arterial calcification

      It appears the ideal dose to use is about 180 mcg/day of MK-7. You can go much higher, but you may not be getting much more benefit than the 180 mcg dose. Of course, it's the dose that makes the poison, so I wouldn't go overboard, but similar to vitamin D (previously thought to be toxic at high levels, with new research showing very high doses are relatively safe), newer research is showing that K2 is quite safe even at mega doses.

      What would happen with a toxic K2 dose? That I don't know. I don't think it's ever been reported, and based on MK-4 studies that used 45,000 mcg/day to be safe, I don't expect there to be much in the way of reported adverse effects.

      Hope this answers your questions.

  9. Dr. Know, I'm confused about the dosage of mk-7 vitamin k-2. I was taking vitamin k-2 at 200 mcg's daily and want to take the mk-7 vitamin k-2. What dosage would you recommend? My capsules are 100 mcg each.

    1. I'm so sorry for the (really) late reply! (For future reference, please use your first name or alias, as comments from "anonymous" get deleted or overlooked.)

      100 mcg of Mk-7 should be fine. According to the latest studies, however, it would appear 180 mcg/day is ideal when taking MK-7. Hope this helps.

  10. Hi Dr. Know, I'm taking a regiment of vitamins and supplements for osteoporosis I am taking Vitamin D, strontium, calcium, magnesium, boron and vitamin k-2. I want to take vitamin mk-7 k-2 instead of just k-2. I was taking 200 mcg of the k-2. Can I continue to take 200 mcg of the mk-7 k-2?.

    1. Hi Cyndi,

      Just to be clear, MK-7 is a form of vitamin K2. What I believe you're likely taking, however, is another form of K2 called MK-4 (please correct me if I'm wrong). Most studies, including the ones I've covered throughout this website) show that MK-7 is much better than MK-4. This is especially true in Canada, where our regulatory body has placed limits on how much we can recommend on the label per daily dose (meaning it's near impossible to find a suitable/therapeutic MK-4 product even if sold illegally under-the-counter).

      So to answer your question, yes, you can absolutely take 200 mcg daily of the MK-7. It appears from a couple studies now, that 180 mcg/day is ideal for MK-7. You can go higher (likely 200 mcg/day), but the effects start to level off after this amount (we see a plateauing of the dose-response curve after about this dosage).

      Let me know if you have any other questions. Have a great day!


    2. Thank you so much. I appreciate your feedback and your web cite. Keep up the awesome work. I value your input. You also have a great day and thanks again. Cyndi


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