Vitamin K2

I recently bought a multi supplement online for bone strength that contains 500 mcg of both Vitamin K2, M-4 and M-7 in a daily dose of 3 capsules. Does that sound like too much Vitamin K? I remember reading someone posting that they had a mini stroke and the Dr. suspected it may have been because the person was taking Vitamin K. Can it cause your blood to thicken? I liked all the other ingredients in the product but was a little alarmed when I saw the amount of vitamin K. Thanks to whoever may know anything about it.

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You can buy the book Vitamin K2 and the Calcium Paradox again on Amazon for a reasonable cost and or watch the video:
I guess I would read all of the literature before purchasing or using any supplement. I think what you say here sounds way over the top too much per day. You need to understand what vitamin K2 is and what it does. I am taking only a 100mcg of K2 M7 daily because I am trying not only to deposit the calcium into my bones, but to heal fractures. This is a higher dose of the vitamin. More than that is not necessarily better.

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IN an observational study recently published in the Journal of Bone and Mineral Research in people with chronic kidney disease (CKD) where the incidence of vascular calcification and vertebral fractures are both quite high, it was observed that those with the highest blood levels of K1 had the lowest risk of vertebral fractures independent of the K2 levels, and those with the highest levels of K2 had lower degrees of vascular calcification independent of their K1 levels. While this study looked only at those with CKD, it suggests that K2 may indeed prevent coronary artery calcification, but it doesn't help with osteoporosis, while K1 is good for bone, but doesn't help with preventing or causing calcium deposits elsewhere in normal people as well.

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Hi Zeke, I don't know that much about it, but it sounds too high to me- or should I say "for" me. I only take 50 mcg MK7 about 4-5 days a week. I started on 180 mcg and ended up with thrombosis in my leg veins. I too remember the lady who had a stroke, but we of course do not know the cause of that- but I believe that was the discussion where I learned that MK7 stays in your system up to 3 days, so it builds up. The MK4 does not do this.
Take care,

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I have just started taking a combo of vitamin k1 and k2 with, of course, calcium and D3 for my diagnosis of osteoporosis. My doctor wanted me to get injection of Prolia, but is have some real concerns about the drug. I wanted to try this natural route for about a year and then have another scan. If there is no improvement, or God forbid, it's gotten worse, then I will reassess my position. I have not had any fractures. I still hate what I am reading about Prolia and the other drugs out there. I tried Boniva and that made me sick with flu like symptoms so that's why the doctor wants me to take Prolia. Any thoughts on this approach would be appreciated. Thanks.

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There are two types of Vitamin K2, MK4 and MK7. The recommended dosage (used in the studies) for the MK4 version (which passes out of the body in 4-8 hours) is 15 milligrams (4500 micrograms) a day! The recommended dosage for MK7 (which remains in the body for 3 days or more) is 120 micrograms a day. So just saying what is the dosage of your K2 supplement total does not give the necessary information.

Vitamin K1 is an issue for strokes because it enables blood clotting(a necessary function) so can interfere with blood thinners. This discussion excerpts a National Osteporosis Society article on K2 and bone loss: 2-mk-7-does-decrease-bone-loss/

Another discussion thread on K2, on this site. itamin-k2-and-the-calcium-paradox/

Highly recommend the book cited above, Vitamin K2 and the Calcium Paradox. However last I checked it was awaiting a reprint and very expensive on Amazon.

K2 has helped me in many ways but need to get on with my day, now.

Report post /ref=sr_1_1?ie=UTF8&qid=1378584486&sr=8-1&keywords=vitamin+k2+and+the+calci um+paradox

Above is the link to Amazon with the book for $13.39 and the Kindle $8.89. While waiting for the reprint, the scalpers had some of the first issues on Amazon for as much as $2,000. So tell me this book is NOT full of valuable information!!

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Hi Zeke37-4n5,

I am taking the OsteoStim which contains 500 mcg of K2. It has 450 mcg of Mk4 and 50 mcg of Mk7, from 3 capsules. I am happy with the amounts. My goal is to take 50 mcg of Mk7 only, since I am rather sensitive to medication and supplements. Mk7 can build up as it stays in our blood stream for over 3 days.

As for Mk4, many studies were done with 45 mg, by taking 15 mg, 3 times per day. I only take 1 to 5 mg per day. I would add a couple of drops of the Thorne liquid onto food (a cookie or pastry will do), twice daily. I am conservative and I also believe that a few mg should be sufficient. The study, published in 2009 “Effect of Low Dose Vitamin K2 (Mk-4) supplementation on Bio-Indices …” by Koitaya et al. ( provided good news: We do not need to take 45 mg of Mk4 per day to get results. The bottom line is that they found 1.5 mg daily to be effective in carboxylating osteocalcin. For correcting osteopenia, I go for a little more. . . .

Hope this helps,

<3 Sylvia <<<<><> > > > > ps. Most days, I only take 2 capsules of the Stim (at lunch and at dinner). I seldom take 3. I also take many "pill holidays" ;-)

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Hi everyone!

As many in this forum, I started with mk7. I took 90 mcg and got some weird heart palpitations almost immediately. I felt bad, anxious, sleepless etc, all the time and had a gut feeling that this vitamin wasn't that good for me so I switched to K2 mk4 to try..

I did some heavy reading on this vitamin and never found anything indicating that it would cause blood clots, stroke or venous thrombosis.
The most trustable source for this I found by reading the indications for the Japanese medicine "Glakay", which is used in Japan for osteoporosis. It has 15 mg (not micrograms!) per capsule and the indication is to take 3 capsules/day= 45 mg/day.
If you read the side effects and contraindications you find NOTHING on blood clotting (that is, if you are not on Warafin).

There are other studies online showing no alteration in blood clotting with 45 mg vitamin K2 if you google around, but for me, the fact that this is a medicine approved since 1995 by the Ministry of health in a civilized country, and that it doesn't rapport anything about increased stroke risk or thrombosis, is the proof that we can take vitamin K mk4 in high doses.
Then it's up to each person to decide whether they think they need 1mg or 45 mg or whatever, but I think it's quite safe.

Here is the patient information leaflet on Glakay for those interested:

I've been taking 45 mg/day for a year and have tested blood clotting and blood velocity and it came back normal.
I take this amount as I messed up a lot with my lifestyle and I want to build as much bone as possible.
Maybe I need less but as I don't know, I prefer to take as indicated for osteoporosis in Japan for some time.
Then I can say I tried this 100%.
Time will show if it helps:-)!

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Others on Inspire have also said that K2 Mk-7 would give them a rapid heart beat, shaky. and they could not sleep at night.

When I first started taking K2 Mk4, I took too many drops of Thorne K2 Mk-4, and had flu symptoms for a about 3 hours..
I can only take about 5 drops.
Every-body is different.

How much D3 are you taking ? That is one of the vitamins that is important for Bone Health.
I have not really heard that K1 does much for your bones, or I could be wrong!...K1 gives me leg cramps!!

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oh, wow, I wish there was some conclusive evidence;( Very confusing.

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Yes it is quite complex, but then so is the body!

Blueberry, my understanding is that about 1/3 of the population has the sleepless and palpitation issue with MK7 and mostly no issues with MK4. We are all different. My daughter in law has a severe allergy to dairy - anaphylactic shock, potentially fatal. This does not mean that others should not drink milk, or that milk is inherently dangerous to humans.

This is a complex subject and it would be good if our doctors were taking it on so they could advise us, but they are mostly not. My (generally mainstream) MD was delighted when I told her I was taking K2. She works for Kaiser, however, so she just gave me a thumbs up and a huge smile, and said it was a good idea. She is not free to prescribe it. Our medical system has some serious flaws, which is why this forum is important. It is not simple, though.

I take K2 primarily for calcium removal in my circulatory system. I have had many indications that it is working, as well as other beneficial effects; skin, hair, memory (I think this is probably due to better circulation in the brain), less reactive to stress. I strongly recommend it. My bones were already in good shape so cannot judge there. I wound up on this forum because a friend recommended that I read the posts here about K2 a year ago.

If you can take the time to read and absorb the recommended book, Vitamin K2 and the Calcium Paradox, I think it is really quite clear and it is extensively footnoted with medical studies.

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Oh, on dosages. I agree with you, Sylvia6789, that the higher dosages of MK4 may not be necessary. I took the high level for quite a while as I had had two TIA's- small strokes with no after effects.
I am now taking 15 mg in am with a breakfast with some fat, and Thorne liquid, 2-3 drops @1 mg a drop with other two meals. Or, if I am traveling, one cap of 120 mcg of MK7 in AM, so that I only have to take once a day. That is just what I have worked out for myself. I think the Thorne is very high quality and the visible effects remained when I lowered the dose so perhaps do not need the 15 mg in AM, and may switch off that and try just the lower dose. But as strokes are so serious and results have been good, do not want to take chances.

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thank you so much for sharing. Can you address the subject of amount? I have read Vitamin K2 and the calcium paradox, but there are people here who seem to think that a much smaller amount would do the job. I've always been one to take the smallest amount necessary to do the job, but this is hard to quantify.

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I take the mk4 5 mg but causes peeling and cracking skin on my nose... so now I only take it every 2 or 3 day.

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Alli, do you also take D and A? There needs to be a balance among them, but I have not seen how you find what amounts, except by trial and error.
Did you read my comment about individuals being different?

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Thank you everyone who took the time to reply and share your thoughts. I will be reading all the referred articles thoroughly and decide what to do. Wish it could be easier for us all.

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Mowglil ... yes I take vit D but not A.. Yes all our bodies react differently but I am wondering if I have to space it is is going to benefit me but I guess I won't know that until next dexa ... or no fractures eh!

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Has anyone taken Osteo Build Rainbow Light vitamins? It seems to have the correct balances of calcium and Vitamins D and K. Plus it has other essential vitamins.

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Alli, there have been reports on this forum that K2 has benefits that do not appear on scans, strengthening the bones with collagen. First person reports from more that one person, newly fracture free. Seeing what it has done with my skin I can credit this. So, I would think it worth continuing to take, even if the scans do not show a change, provided you are fracture free.

Seeyamate, looked up the Osteo Rainbow and it has no vitamin A and a low dose of K2 MK7 (56% RDA by their measure), so I don't think it has either the correct proportions or enough of the K2. Still might be better than no K2, but would not be my choice.

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MowgliLea. How much vitamin A should be taken? I know the dose is low for K2 but I thought you should take high doses of K2? Where would get Vitamin A? I don't think I've ever seen it at the pharmacy

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