Vit K2-7 Heart Arrhythmias and Palpitations

Dear Friends,

I have already posted a discussion on which is better Vitamin K2-7 or Vitamin K2-4 and the overall consensus there seems to be that K2-4 has much less side effects. Please see this discussion if you wish to get a fuller picture: ontroversy-on-vitamin-k-either-k2-4-or-k2-7/

Now I would like to request you to please help out in this second discussion with your personal experiences!

Has anyone taking Vitamin K2-7 had heart palpitations and heart arrhythmiaa?

If so, has he or she been absolutely certain that these were due to the K2-7?

Did they stop taking K2-7 and did the heart palpitations and arrhythmias stop right then?

I am asking this question - because it is this side effect of Vitamin K2-7 which is making many people scared of taking the vitamin.

Also, it is said that these ill effects come about if you take Vitamin K2-7 greater than 45 mcg, and if you stay within this limit then nothing bad happens.

The other side effects of Vitamin K2-7 are said to be a state of excitement and exhilaration and also its accompanying sleeplessness, which are not that serious.


I know that the majority of folk have decided on taking Vitamin K2-4 which is said to not to have these bad side effects. But has anyone taking Vit K2-4 also experienced these ill effects on the heart?

Whatever may be the benefits of Vitamin K2 on the calcification of arteries and the bones -- no one would like to take this Vitamin at the cost of one's heart.

Best wishes and thanks in advance,

Edited July 23, 2011 at 1:37 pm

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169 replies. Join the discussion

What happened to this thread?
It was SO Informative...
This thread was 3 pages.
Please bring it back..


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Are you talking about this thread ? ontroversy-on-vitamin-k-either-k2-4-or-k2-7/

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Dear April1995!

It is so nice to be in touch with you again! I had been thinking of you. I hope you have been all right and well and happy. Thanks for coming to this discussion. I think you are right - this discussion is very much like the earlier one I had started, except that the earlier one asked which of the two was better -- MK-4 or MK-7, and the general consensus in that discussion came out that MK-4 was better.

I really should not have started this second discussion as it may be redundant, repetitive! But I thought it would be better to get the final picture on MK-7 rather than give it up altogether. It was basically these two dreaded side effects of MK-7 which were making it scary - the heart palpitations and the heart arrhythmia which some people were reporting. but it was not certain, whether MK-7 was causing them or they were just incidental.

I thought maybe if people could post simply about their heart side effects from Vit MK-7 we would come out with a clearer picture.

Thank you and it is so nice to hear from you like old times in all the discussions when you were so helpful.

With every good wish and warm regards,


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Dear Lela52!

Thank you for bringing the link of my old discussion to fore! Yes, you are right that is the discussion! I hope this discussion will not become redundant -- but I merely wished to have people post their heart experiences for Vit MK-7 so that we would finally know whether it can be dangerous for the heart and give it up altogether!

Thanks again for joining in!
Warm regards,

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Hi Priya

It's always good to hear from you.

I haven't been able to find Vitamin K capsules or tablets (MK-4 or MK-7) in decent amounts in Sydney, Australia.
They can't be bought on their own - all I have seen are tiny, useless amounts thrown in with multi vitamin tablets.

I tried to consume Natto (fermented Soybeans) a few times but the taste was so strong I had to stop.

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Thank you. Your right that is the posts I was talking about ..duh lol..
Those post are very good..

Hello Priya,

I agree with you about K2 MK4 and why.

This is the discription on on, Thorne K2 Mk4:
Vitamin K2 exerts a more powerful influence on bone than does vitamin K1. Vitamin K2 is a series of molecules known as menaquinones, some of which are found naturally in fermented soybeans. The most common and well studied of the menaquinones is MK-4. Thorne's vitamin K2 is MK-4. Vitamin K2 appears to offer significant benefit for supporting bone health. Although much of the vitamin K2 research has been conducted on postmenopausal support for bones, because vitamin K2 does not have any estrogenic effects, vitamin K2 also offers bone support for other populations, including anorexics, dialysis patients, individuals with Parkinson's disease, those who have cirrhosis of the liver, individuals who have had a bone marrow transplant, those immobilized after a stroke, and individuals on chronic steroid therapy.

$59.45 & this item ships for FREE with Super Saver Shipping.
Vitamin k2 liquid 1 fl oz
by Thorne Research

This is what one reviewer had to say about K2 MK-4:
This review is from: Vitamin k2 liquid.
I can't say enough good things about Thorne's Liquid K2. It is the MK-4 type of K2, which is the MOST DIFFICULT to find, mainly because it's the most expensive to make (which is why you find ALL the manufacturers seriously "PUSHING" MK-7, which is easier and cheaper to produce), but MK-7 converts to K1 and K2, which is very, very BAAAAAD for someone on blood thinners (anti-coagulants)!!!!! MK-4 does not convert to K1, so it is MUCH safer.

If you are looking at this product, then you've either done your research on K2's (specifically from MK-4) beneficial impact on bone and cardiovascular health, or the American Diet's common deficiency in K2, or someone else has told you about it, so I'm not going to go into everything it has helped us with, but I will say it has made a big difference in our lives, and it's great to be able to find it in liquid form which makes it easy to take! I'm so happy to have found a source for it.

I ordered the K2 MK-4 today..I'm hopeing I did the right thing, as I want this to work, and I think its expensive, but it seems
to be the best one out there.
When I have taken K2 before, I would get leg cramps.
From what I have learned from Priya's other thread, I was taking the wrong K2, or what ever it was!
That said, I called The Thorne Co. yesterday. Then I called a Homeopathic Health food store in New York, they did not have
it in stock, but she told me I should not get leg cramps. The K2 MK-4 by Thorne is a very high grade, and it is the right K2 to take
if you have Osteoporosis. She also mention how bad the Drugs are for Osteo, and they really do not do any good.
She knew I was not going to buy it from her. I was going to buy it from Amazon.

Take Care,

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A SIMPLE answer:

Was taking 100mcg of K2 and experienced a Ka-Thumping feeling in my heart ......reduced my dosage to 50mcg and it went away..........all there is to it .....knowing what I know about K2, I will take it for the rest of my life....

Additionally, has had a profound positive effect on my prostate.....which is just 1 more reason.....50% reduction in cases of prostate cancer......

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If you have access to Amazon on the internet and put in vit K2 you will find several sites available. I live in the UK and buy Carlson K2 (Mk4) and Dr's Best K2 (MK7). The Carlson was sent from the USA and arrived OK. I am not saying that these are better than other makes, only that a range is available via the internet.

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i have been taking k2 -mk4 for the last couple years. 120( micrograms or) mcg's. haven't experienced any issues i could directly relate to that particular vitamin. i take AOR and the cost is if i remember correctly about 25.00 for 60 tiny vegi caps.

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I daresay most of you have read this in the previous thread, but just in case here it is again. (I was suffering horrendous symptoms, my heart was all over the place and hearing my heart beating in my ear all the time was very disconcerting. My docotr was very concerned and told me to stop jogging and referred me to a vascular consultant. This consultant could find nothing wrong. At first I did not associate my vitamin K intake as being connected. I put a message on this site and someone replied and told me that she had had heart arrhythmias which stopped about a week after she stopped taking vitamin K.

I had taken vitamin k because,) 'Reading that natto was so beneficial in promoting bone and cardiovascular strength, I began taking Jarrow Formula's vitamin K2 as MK-7 (derived from natto). I was taking one a day (90 mcg), but began to suffer severe arrhythmias and pulsatile tinnitus.' I stopped taking all vitamin K and sure enough within a week my symptoms stopped. 'The only vitamin K2 MK-4 I could find was Life Extension's SuperK with advanced K2 complex. Each gel capsule contains 1000 mcg K1, 1000 mcg K2 as MK-4 and 100 mcg K2 as MK-7'. I started taking these expecting my symptoms to return BUT, 'Surprisingly, although these contain slightly more MK-7, since I have been taking these I have had no occurrence of arrhythmias and the tinnitus has vanished!

It doesn't really make any sense! I wonder if anyone else has had a similar experience.

I live in the UK and had to get the vit K shipped from America'. Will follow LynH's advice and try Amazon in the future.

I think this site is wonderful as I have received such knowledgeable help. Most of you are so much more informed than most doctors! Thank you so much to everyone.

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Hi Blanky,
I too am on K2-Meliquinone, 45mcg. daily. My heart does jump around at least once a day and when I'm lying down, I hear my pulse in my right ear. At first, it was just occasionally, but now it is everyday. I was taking double that amount, but have cut back to just one pill a day. My K2 is in combination with D3. I purchase these from Swanson vitamins online or the Vitamin Shoppe.

Not sure what to do about the K2....guess I'll keep taking it. I wonder if I should switch to the M-7 K2?

This is a great thread.


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Dear Phil!

Thanks for the encouraging news. BUT Which K2 was it? K2-7 or K2-4? Please do let us know! If you are right that it was K2-7 then I may think in terms of reviving it. I stopped taking my stock of the medicine a while ago when I read of the heart effects! I was taking only 45 mcg of K2-7-- so I suppose that would not do anything to the heart would it?
Thanks again, you are a pillar of knowledge here!
Warm Regards,

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OK....I just looked at my vitamin bottle and the vitamin K is listed as Phytonadione. Anyone heard of this? I'm going to go online and study us on it. It is the vitamin Alive by Natures Way. Would this K give you palpatations or skipped beats?


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Thanks, LynH, I will do this as I do have access to Amazon.

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I always have heart palpitations. I stopped the Life extension which has both forms for at least a week and it did not make a difference. Now I still have some of it , plus I have the Carlsons 5mg. mk-4. I alternate them and when I am out of the Life extension I won't order that again, just the Carlsons. It is so expensive. Last year I was taking Complementary Prescriptions from the naturopath which is just MK-4 menatrenone and each capsule is 15mg. and the dosage was up to 3 times a day but I never did that. I can hear my heart in my ear. I wore a heart monitor for 24 hours and had an echocardiagram (ultrasound) and I have lots of PVCs but not so many come in triples so supposedly this is benign. Well I read an article that said this type of heart turbulence is actually not so healthy, but I don't want to take beta-blockers, yet another drug. I take magnesium for bones sometimes, but it is supposedly good for the heart. Also coq10 and fish oil. I'll keep this thread in mind when I completely have stopped any mk-7 for a long time.

P.S. a Life extension article reported on osteoporosis appearing in less healthy individuals. Not surprising.

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Since I was about 19 yrs old, I would get irregular heart beats (IHB). As I got older, they became stronger. I Wore halter monitors 3 different times, and nobody (cardiologists(SP?) could figure out what was going on!
About 17 yrs ago, I met a women that was into health..She told me to take Hawthorn Berry,its a herb..After a couple of months of taking it the irregular heart beats have stopped.
I still take one a day..
Btw, my IHB where so bad the only thing that would stop them, is when I would press in on my chest!
Hawthorn berry is a heart muscle strenthener.
I find it hard to believe what a vitamin co. says about what they sell!.
A Homeopath told me to take 15mcg of the K2 MK4 3 times a day..It leaves the body fast, this way its working to carry
the calcium to the bones not the heart..

Does anyone know why there are certain K's that cause irregular heart beat. Or does it have something to do
with the Blood cloting effect? !!

Is the K2 your taking, The K2 MK4??
Never heard of Phytonadione!

I'm thinking your heart symtoms stopped even though you were still taking the MK7, because you are also taking the
K2 MK4 with it time you might want to try just the K2 MK4!

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HI priya, I have been taking 45mg. of Glakay which is mk4 for five months and 100mc of mk7 for three months. The only side effects I have had is sleeplesness if I take them in the evening. I have not had any negitive side effects at all. I believe this vitamin is the best thing to come along in a long time. I hope you can sort out your problems concerning it. Cheers, Ricardo - -

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Dear verginia!

Its so good to be in touch again! Thanks for joining in the discussion! I hope you get the answer you want from someone visiting this discussion. I have heard and read that Natto is unbearable! You are so right!

Best wishes,

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Thank you shiner1. It is yet another feather in the cap for Mk-4!
Warm regards,

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