vitamin K2 side affects

listen to your body ,it is the best indicator of whats working for you & what isnt
vitamin K2 came highly recommended for osteoporosis, even so before taking it I researched it thoroughly and everywhere they said vitamin K2 is beneficial for osteoporosis and the heart
I had been taking vitamin K2 complex for 3 months and slowly developed a heart arrhythmia it became so bad I seriously considered seeing a heart specialist
I never had arrhythmias before , only the odd palpitation so sought a reason for it & vit K2 was the only new addition to my list of supplements
I stopped taking it to see if it would make any difference and within a week more arrhythmias

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What was the dosage of K2 in the pill u were taking. There are some irresponsible manufacturers touting K2 as high as 1000mcg. Most responsible vendors are only putting in 50 or 100mcg. Too much of a good thing can be bad!



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I know there are going to be those who highly disagree with me, but I have come to the conclusion that just as meds are over-prescribed by doctors, so are vitamins and supplements. When I looked at the dosage of calcium I was taking and compared it to normal amounts, I didn't like what I read. I eat a lot of dairy and thought I must surely be taking too much calcium. First of all, the calcium was seriously upsetting my stomach--even the calcium citrate, which isn't supposed to be as bad. Then I started reading about calcification of the arteries...well, I get calcium deposits in my nails and skin WITHOUT taking supplements, so guess what, I take calcium just a couple times a week now, and with it I take a low-dose K2 tablet. I cut my Calcium in half and take half at one time and ther other half later in the day. I just can't tolerate that high level of calcium. The same thing with D. My Vitamin D blood levels are normal now, but they still want me taking that high level of D--800 mg I think it is...but I only take what's in my multi--400.

Just remember this: all those fat soluble vitamins (A, D, E, K) stay in your body and can build up into toxic levels. So can minerals. There is no real guideline for vitamins--everyone seems to be taking different amounts and different combinations. That's got to be a bit of a worry for some--it is for me. Everyone seems to have their own idea of what is good and what combination of drugs to take, when to take it, etc. I have decided to listen to my body. If I listen to my doctor and take that high dose of calcium, I'll be sick to my stomach every day. The fact that I have existing calcium deposits doesn't seem to concern anyone--but those who are unconcerned aren't living in my body.

Too much of a good thing is NOT a good thing. While supplements might be good for us, they are meant to supplement our food. Everyone is different--I eat a high calcium diet so I doubt I need as much calcium as some. That's just my opinion...we all have them.

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Potassium should never be taken without your doctor monitoring your blood level. It is a critical element and either too much or too little will impact your heart function, and in some cases your level of consciousness. It can even lead to cardiac arrest. So if you are thinking of adding potassium to your regimen, please do discuss it with your physician.


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hi milandel, I was taking a vitamin k complex ingredients as follows
k2 as menaquinone-7 100 mcg
k2 as menaquinone-4 1,300 mcg
k1 as phytonadione 1,000mcg
and Im not on any medication for it to have clashed with

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The type of K2 that helps to put calcium into yr bones is the menaquinone 7 type (all research seems to indicate that). So 100mcg of that is all u need as a supplement. For K1 u can take a multi and eat lots of greens. I am taking 50mcg K2-7 twice a day just after meals. This is important coz like many other vits, K2 is fat soluble. U need to get enough K2-7 for yr bones! Unfortunately the docs who prescribe dangerous meds are not well informed about vits! Hope u work out a way around yr arrythmia!


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if you do a search you will find that vitamin k2 supplementation has been discussed at length
latest research indicates that you should be supplementing with mk-4 and mk-7

quote "there is a difference between MK-4 and MK-7. latest research indicates that MK-4 strongly activates transcription of two specific genes in osteoblast cells. Osteoblasts are cells that create bone tissue. The genes are GDF15 and STC2 and they're involved in bone and cartilage formation. They tested K1 and MK-7, and in contrast to MK-4, they did not activate transcription of the genes in the slightest. This shows that MK-4 has effects on gene expression in bone tissue that MK-7 doesn't have."
I dont have arrythmias since I stopped taking vitamin k2

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SWF, You bring up a good point.
When I take K2, I get painful leg cramps..Allot of the calciums seem to have a small amount of K2 in them, but I still get leg cramps!
If I eat too much of the Greens I grow in my garden, I get leg cramps.
I think I have to much K2 in my body, or its just telling me, stay way, its not for you. or I have sometype of chemical inbalance!

We are all different, and what works for one, does not work for someone else.

I have cut down on my calcium intake, or do not take any at all. Just in my food. I'm still trying to figure
out which is the best calcium, that goes to our bones, not to our arteries.

From what I have been reading and told by some friends, is to try "Stardard Process".
There all Organic, they grow it. and there not high in vitamins. I also think maybe all these vitamins are hard on
our Kidney's!


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Hi Shawnmarie, I agree with you so much! Doctors don't know themselves (I'll bet the little they do taken from the same source we take it - internet! They aren't going to take the hours necessary to properly research for us...). It's good to read and to listen, then as you say, only finally listen to YOUR body!

"I cut my Calcium in half and take half at one time and ther other half later in the day. I just can't tolerate that high level of calcium. "

I don't know how much calcium you take per day, the standard dose, I believe, is around 1200 mgs or 1500 mgs per day, but, they warn to take no more than 500 mgs 3 times a day. So, whatever total amount you take per day, perhaps you should divide it in 3 per day instead of 2?

What you say also can be applied to the fact that I just wonder whether some of these vitamins have any effect at all??? lol! Leidi

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Shawnmarie AGREE!!
I just had a surprise the other day even though I run 3-5 miles 3 times a week, take 4,000 IU of Vitamin D3 and eat nothing but fat free or low fat main artery to my heart was 95% blocked. Then came the calcium report, then came the the NIH report that said that the majority of plaque is made up of calcium.

Vit K to put calcium were it is supposed to go and Vit D3 2,000-4,000 IU will get you more than you need.......I clogged up my arteries in just 8 years because I just took the D3 and so the calcium stayed in my blood and went into my artery walls instead of my bones.......

Discussion: In this pooled analysis of around 12 000 participants from 11 randomized controlled trials, calcium supplements were associated with about a 30% increase in the incidence of myocardial infarction and smaller, non-significant, increases in the risk of stroke and mortality.

(Scroll Down to Discussion)
Note: Logic says it is not just the supplements that you must consider but your total intake from all sources especially milk

From the National Institute of Health:

Increased Blood Calcium and Vitamin D in-d.html - inbox/12d6879d14506649

Our nutritionist showed us what she believed to be the best calcium on the market, derived from Algae or plant derived. See link for Bone Strength below, if you scroll down you will find the contents…… Remember it is the balance of the nutrients contained in this product that is important since they work without the other can be bad news. onus-20-More-FREE

Who Will Tell the People? It Isn't Cholesterol

Vitamin K
By FAR THE MOST INFORMATIVE INTERVIEW I HAVE EVER LISTENED TO ….A MUST LISTEN (Set aside about an hour to listen to this interview):
Go here to listen to an interview of Dr. Vermeer: memberid=5263319

IP6 Info. age=1

Resveratrol Info. ?source=nextag&utm_source=nextag&utm_medium=ppc&utm_campaign=RESV#pricegrid

CBS News presentation

Plaque Removal in-d.html

Hope this info helps and pls pass on to help other...Phil

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To SWF - Got to talk to you about this, First I took vit. Ultra k2 (menatetrenone) by Complementary Prescriptions recommended by naturopath - 15 mgs. maybe 3 or 4 times a week. ( I didn't always remember to take it and it was expensive ) In studies it was up to 45 mgs. day. I think this is the mk4 version which is taken in much higher doses than the mk7 - according to Mercola youtube that is with Dr. Mercola and this Vit K expert. Then I switched to Life extension advanced k2 complex that maybe I take 5 times a week so guess what

My occasional PALPITATIONS WAY INCREASED.....I had to have a 24 hour halter test and an ultrasound - they check out as benign but I don't like the way I feel. I got to stop the K and see if that is it.

I stopped a medication I was taking, but that did not make a difference. I take so many supplements. I would really doubt K, but I am going to stop for at least a week as you did and see what happens.

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dogbone, I was taking nutraceutical ultra vitamin k with advanced k2 complex and never suspected it to be the cause of my arrthymias until I realised it started shortly after I started taking k2 and there was nothing else new to my regime
my arrthymias slowly went away within a week
it could be the cause of your increased palpitations only way to find out is to stop the k2
keep us posted as to your progress

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Your observation that the noticeable lumpy heart beats started months after taking the K2 with MK-4 and MK-7 suggests that the lumpy heart beat may be a result of the MK-7 faction which is known to build up over a longer term. The MK-4 faction is natural to the body and clears out in several hours, this being the reason for patients being given 15 mg of MK-4 three times a day in research and treatment. MK-7 tends to stay around which is why blood levels of MK-7 build up.

You could try stopping the current pills with the MK-7, wait for the heart beats to stay regular, and then try a Vitamin K2, MK-4 faction only pill to see if it avoids having the same effects without the MK-7 faction. Its possible to get 200 mcg of MK-4 from natural sources such as goose liver pate. Smaller pills are available and even eating cultured cheeses give significant decreases in heart disease in Dutch studies and probably in bone health as well.

I had noticeable heart beats too as a result of a stressful situation years ago. This was very annoying to say the least and might be contributing to the heart situation here. If you find too much stress in your life, it may be that the solution needed is really some stress relief or a prescription for Xanax.

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Hi Dogbone,

Are you saying that you took 15 mg of Vitamin K2 daily for a while, then switched to the Advanced K with Vitamin K2 Complex? Did your heart palpitations start after switching to the Advanced K brand? This would be most interesting if true because the Ultra K2 didn't sound like it was giving you palpitations while you were taking it.

If true, that would suggest that the MK-7 faction is the cause of heart palpitations. The MK-4 faction has been listed as having very few side effects in research. Keep us posted.

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I am eating natto instead of taking a pill for Vitamin K2. Natto is the highest food source for Vitamin K2.. You only need to eat about 1 TB per day. It is fermented soybeans and I find it frozen in little serving size packets at an asian market. It does not taste good, but I have gotten used to it and eat it like a medicine. It is more palatable with a little soysauce on it. I do not have any side effects. I think it is generally safer to get minerals/nutrients/vitamins from food than from pills

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Hi Seacoral,

Is the natto you eat organic? I have cut out soy products that are not labeled "USDA Organic" as 90% of the soy grown in this country is GMO. I would rather eat natto than take the K2 suppplement, but have yet to find a certified organic source. Thanks!

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No, I wish I could find organic, but never have. But mine is from Japan or Korea..

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I tried life extension K2, also had problems. Can't remember about palpitations but I do remember feeling tired, sore bones and nauseous (this was after only 2 weeks). Tried it several times and always the same, so I threw out the rest of the bottle. I would like to try the K2 MK4 only and see if this is better (supposed to be good for teeth and skin too).

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personally I think about 1/2 of all items in health food stores are a total waste of money or even bad for you.

We should not only choose our meds with great care but also our alternative treatments and supplements. There are dangers in both

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I used to take (several years ago) the equivalent to the Life extension k2 complex by taking their super booster supplement. They both have:
Vitamin K1 (as phytonadione) 1000 mcg
Vitamin K2 (as menaquinone-4)1000 mcg
Vitamin K2 (as menaquinone-7) 100 mcg
I didn't have bad palpitations then. Then I some point I stopped that. Then 2 years ago roughly I started the menatrenone only (which I've read is the same as MK-4)at a high dose but not so regularily. Each pill has 15 mgs (15 times the amount in LEF pills).
That was expensive so I'm not sure exactly when I switched to the LEF K complex but about the time noticed more palpitations.
Now I am alternating the LEF super K complex with a Carlsons 5 mg. menatrenone (mk-4).

BUT I think I will stop for 2 weeks and see if there is a change on paplitations and foot cramps sometimes. It may be stress or another medication. This calcium in the arteries stuff freaks me out. I'm taking less calcium now and half the dose of strontium (340 mg). Especially without the K isn't all this calcium dangerous. I have taken a variety of calciums for so long, including Lane Labs. My Dexa improved with the strontium. I don't think we know enough.

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When you had your Dexa did you tell them you where taking strontium?
Sometimes Strontium will show you have inproved, as I believe its heavier, and shows thicker on a Dexa scan!
Or someone here can explain it better then I can.

When I was about 20 yrs old, I would get a irregular heart beat, although not bad. A few years later it got worse, and
I Had 3 halter monitors at different times, and nothing showed up!
As I got older it became so bad, I would have to push my chest in to stop a wierd type of grinding it would start to make!
About 17 yrs ago, A met a women who was teaching about health / Vitamins etc.
She told me to take "Hawthorn Berry" for the irregular heart beat, with in a few months or less
the irregular heart beat Stopped!
To this day I still take it everyday. If I stop for a couple of weeks or so, it starts again.
I have learned more about Hawthorn Berry and it makes the Heart Muscle Stronger.
Of course my Cardo Dr. never heard of it, and thinks I'm crazy!! But all my heart tests are fine.
That said , in 03, a eye Dr. gave me a Drug for a short time (for migraines from a eye accident), that
caused me to have a heart attack. I do Not have any heart damage. I have thought maybe cause
I take Hawthorn berry!!

Hawthorn berry is a herb and can interfer with some Meds I believe!
But All I know is, it works for me :-)

Soy was orginally grown to fatten up Cows, Pigs, Chickens etc. its cheap and We are getting fat and full
of cancer from soy, and its causeing Thyroid problems, even if its Organic.
The only good soy is Formented, and then people eat very little of it.
I try to buy just about everything Organic, which cannot be GMO.
Monsanto controls GMO and is making a fortune from it. People with money
have power! Besides Monsanto doesn't care about us, only about money.

Take Care,

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