Dear Mark: Vitamin K2

Dear Mark,

I’ve been hearing a lot about vitamin K2 lately. Should I be taking vitamin K2 supplements or is a Primal diet sufficient?


Thank you, Kate, for the question.

You find it in politics, fashion, entertainment, art, even cooking: the “it” figure, new notable, celebrity du jour. As odd as it is, the seemingly humble world of micronutrients isn’t immune from spotlight blitz. Some vitamin or mineral, subject of a timely string of studies, gets thrust into the limelight, and the medical media jumps on the news. Sometimes the hoopla is warranted. Oftentimes, it’s overblown. Most of the time, it’s here today gone tomorrow. Such an odd frame for public health education, I think – and likely the reason many people shut out such reports all together. One day, it’s a miracle nutrient. The next, it’s torn down as “not all that.” Recently, vitamin D has been the one to adorn the marquis. But there’s another novel nutrient chasing its heels: the nebulous, little known vitamin K2.

“K2? Vitamin K. Hmmm. Don’t recall much about that from high school nutrition class. Isn’t it in, like, spinach and stuff?” “Vitamin K. Oh, yes, I think our kids got vitamin K shots right after birth. Was that vitamin K2?” Well, yes to the first, and “close but no cigar for the second.” (That would’ve been vitamin K1.)

So, what’s the deal behind the buzz anyway?

Here’s the story. First, the breakdown. Vitamin K: fat-soluble vitamin – or group of vitamins otherwise known as the naphthoquinones (K1, K2, K3). Call vitamin K1 (phylloquinone) the plant party of the bunch. The spinach association? That would be a source of vitamin K1. Some other K-friendly choices (kale, spinach, Swiss chard, mustard greens, parsley, broccoli, Brussels sprouts, asparagus and avocado) serve up a decent helping. Incidentally, the body can “make” K2 from K1, but it’s not a 1:1 conversion. Though many sources put it at 10:1, the presence of fat (oh, lovely, lovable fat) enhances that conversion process. Finally, vitamin K3 (menadione) is a synthetic version of the vitamin that has limited place in certain medical treatments but is generally considered unsafe and unnecessary for general use.

Vitamin K2 (menaquinone), the nutrient of the hour, has an interesting background. It’s the product of fermentation and usually of intestinal bacteria – either human or animal. Good sources? Meats and dairy products from pasture-raised animals – especially butter and organ meats, aged and curd cheeses, as well as fish eggs. Nonetheless, the much touted mega-source of K2 is natto, a traditional fermented Japanese dish consisting of sticky soy beans that offers a powerful nutritional punch but a rather limited flavor appeal to outsiders.

(As an aside (for those interested), the picture gets more detailed. Within the vitamin K-club, K2 fans out further into various forms (referred to as MK-n), the most talked about of which are MK-7 and MK-4. MK 8-10 forms exist as well. The MK-7 form of vitamin K2, the form that natto champions, lasts a number of days in the body, but MK-4, a shorter span form, comes with the more readily available [and widely eaten] eggs, pasture-raised meats, aged cheeses, etc. Grok is salivating as I type.)

So, what’s the big deal with this nutrient? The full compilation of recent research underscores the idea that K1 and K2 should be appreciated as separate nutrients with distinct physiological actions and benefits. K1, the more familiar vitamin, is known for its key role in directing blood-clotting in the body. (A K1 shot at birth – or series of drops in the first few weeks of life – are common practice in many countries to curtail hemorrhage incidents in newborns.) It also shows anti-inflammatory properties.

The picture for K2 seems to be a bit more varied. K2 appears to be especially key in maintaining bone mineralization and limiting the formation and lifespan of osteoclasts, cells which break down bone. Researchers are increasingly optimistic about K2’s potential for those with or at risk for osteoporosis but are looking to further studies to confirm this association. (Incidentally, K1 alone has not shown the same effectiveness for those with osteoporosis.) In the meantime, other research suggests that K2 may aid cardiovascular health as well by helping prevent or even reverse arterial calcification, a known contributor to cardiovascular disease. But that’s not all. Researchers are also looking at K2 (specifically MK-4) as a therapy for rheumatoid arthritis. And, wait, there’s more! Researchers are also examining the potential of K2 in the prevention of prostate cancer and in the complementary treatment of leukemia and lung cancer.

“But if it’s such a wonder nutrient, why doesn’t it lace a quarter of grocery store products like omega-3s seem to now?” (Oh, there’s a whole other ball of wax.) Besides being a little understood nutrient, the (legitimate) concern has been that many people are on anti-coagulants like Coumadin/warfarin. In fact, they’re generally in need of it, since Coumadin is a vitamin K antagonist. The worry isn’t so much that these people intake vitamin K (especially K2) within their normal diets but that they maintain a consistent dietary measure of it to allow for stable dosing of their anti-coagulant meds. (A complex dance, to be sure.) But I’d suggest that there are other increasingly common medications (digestive related prescriptions and antibiotics) that can limit the absorption of K and alter the body’s ability to naturally convert K1 to K2. Hmmm.

The fact is, for a healthy person not on medications, adequate vitamin K2 is easy to get from the Primal eating plan. Although an RDA for K2 hasn’t been established, Dietary Reference Intakes for vitamin K1 suggest between 90-120 µg/day. (I’ll be on the lookout for updates on K2 doses, but I’ll note that toxicity doesn’t appear to be a problem with vitamin K, and no UL (Tolerable Upper Intake Level) has been established.)

So, how do we get there (and ensure a little extra for good measure)? Undoubtedly, natto has its claim to fame, and kudos to the beans and all who eat them. However, the long-term benefits of (and need for) K2 was undoubtedly relevant to Groks all over the world. A good Primal eating plan (with or without the addition of natto) provides what Grok and we moderns need: grass-fed and rich organ meats, unapologetic egg yolks, ample veggies and greens (with plenty of fresh oils and pasture-raised butter fat, of course!), and – for those who enjoy them – grass-fed cheeses. For specifics, check out a K2 content graph from the Weston Price Foundation.

And that brings us back to the celeb-factor. Sure, we live a very different life from our ancestors: pollution, stress, longer life spans in some cases, etc. Some things we can’t change, but other things we can. A good Primal eating plan that serves up a wide array of nutrients – in the way Grok and his folk ate them (fat, protein, fat) – makes good plain sense. Our current society with its painfully limited and drastically skewed nutritional practices will naturally hit up against deficiencies – both relative and extreme. Add to this the nutritionally depleting cocktails of digestive and antibiotic prescriptions so many people are on these days, and you’ve made several million borderline cases inevitably bad. The result: a good faith but ultimately misguided, “miss the forest through the trees” mentality of “limelight” nutrition. (“K2 to the rescue!”)

Is vitamin K2 an overlooked, underappreciated nutrient that can offer substantial benefits? I believe absolutely yes, and I’ll look forward to reading more studies (and even the popular media reports) in the coming months/years. I love that K2 may serve as an effective and natural supplemental therapy for those with certain medical conditions. Also, for those on digestive or antibiotic prescriptions, the news offers sound advice to see your doctor about getting levels checked and considering supplementation. But what about the rest of us? What are we to garner from the research, the spotlight, the scientific scuttlebutt?  Consider the take home message on K2 as this. Good science has uncovered the fact that K2 is part of good, necessary nutrition. But good nutrition – from a dinner plate or a quality supplement (or both) – isn’t a matter of star performance but of solid ensemble rapport. (And, how could we resist? Yet another reason to go PB.)

Questions, comments, additions, discussion? Let me know your thoughts.

yamada3 Flickr Photo (CC)

Further Reading:

Grok Didn’t Take Supplement So Why Should I?

Scrutinizing Soy

Previous MDA Coverage of K2

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About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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80 thoughts on “Dear Mark: Vitamin K2”

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  1. Thank you for the explanation! I now know why the Damage Control Master Formula doesn’t have any vitamin k in it!

  2. Thanks for the post today. I learned a lot, as always. I’m always impressed by the detail you provide in each post. At least if I hear the “buzz” about Vitamin K2, I’ll know where I heard it first and be more informed.

  3. Wow… that is everything I needed and didn’t need to know about vitamin k. Thank you for all the info Mark!

    The SoG

  4. Mark,

    Like to see your take on B vitamins and the absolute waste of them in drinks these days…since the majority of them just end up going through and never being used if you catch my drift.

  5. Didn’t know about that. But I guess that’s why I’m on here, Mark 🙂

    Hm, seems vultures get a good portion of K2, no? Eating fermented dead animal and such… Speaking of fermented – the English lords and ladies are said to have a taste for fermented game. And, the french love their stinky cheese.

    Now we know WHY.

    It’s all about vit K2.

    I knew those rich b******s were onto something LOL!


  6. Mark,

    I’m one of the rare westerners that LOVES natto.
    I stopped eating it over the past 3 years because of primal/EF life style.
    Is it ok to eat you think even though it’s soy?
    Eat as a treat every now and than perhaps? Or just a no-no?
    Thanks once again for the informative post.


    1. Soy is one of those few earth-foods that I would not recomend. Us women should stay away from soy, and genetically engineered, or unorganic soy is a big no-no to us all, but I believe guys dont have to worry about it as much.
      Fermented soy is much different, though, and highly nutritious, but until further studies come through about fermented soy, I would stick mostly to other fermented foods.
      But natto, unlike tofu or tempeh, is hardly like “soy” at all! It is concidered by trusted natural health gurus to be one of the healthiest foods on the planet. That difference? I’m not sure. Is it fermented longer? In a different way? Still not sure.

  7. Very Interesting! I’d never thought about vitamin K2,really learned so much from this post.

    Great question Kate!

  8. One of Stephan’s K2 posts at Whole Health Source was linked above, but he has several others as well as peripheral stuff on it.

    They can all be located here:

    Because of Stephan’s work here, I read also that Chris Masterjohn piece at the WAPF site, then read most of Nutrition and Physical Degeneration, probably the most important book on nutrition I’ve ever read. Price studied a bunch of non-industrial cultures in the 20’s and 30’s and documented their excellent dental and general health (they didn’t brush, floss, or have dentists, either).

    I’ve been on K2 (MK-4, the kind made from K1 by mammals, for other mammals — as Stephan puts it) supplementation for maybe six months now. I’ve posted some of my experiences with it:

    In general, plaque dissolved on my teeth within a few days and has never returned. I used to have to have cleanings 4 times per year to remove huge plaque buildup. A Paleo diet improved that a lot, and K2 has rendered it a non-issue; so much so that I don’t even brush my teeth every day anymore. I wake up and they are always pearly smooth.

    If you’ve ever been on an antibiotic like tetracycline, you may have noticed how soft it makes your skin. Same result with K2, virtually over night.

    Within about 3 months, the strength of my fingernails have at least doubled. They are actually highly useful tools, now. Very functional, and they never break. I’m sure Grok put his fingernails to good use every day.

  9. Animal foods really aren’t a very good source of K2, except for hard cheeses that have been fermented by bacteria, especially Swiss-type cheeses that have been fermented with by a specific type of bacteria called propionobacteria).

  10. Great summary about vitamin k2, I appreciate this thoughtful post. However, your comment that humans NEED to eat meat, is false. Humans can be healthy eating meat, but they can also be healthy not eating meat. If there is ever any doubt just go to and see for yourself.

  11. I am a coumadine patient and am curious of the effects of K2 on the INR that I work so hard to maintain.

  12. A cardiologist told me last week that K-2 was potassium. Is that so?

    1. I asked our pharmacist about K2 and he said it was Potassium. Guess he and the cardiologist make a fine pair. Am going to ask my doctor about K2 as I cannot take osteoporosis medication of any kind.

    2. Vitamin K2 is something totally different from Potassium the chemical letter for Potassium is K. Tell your cardiologist to go back to basic chemistry class.

  13. Robert, that’s hilarious. The symbol for potassium in chemistry is “K”, which I guess is what confused your cardiologist.

  14. is k2 safe to take with other medications such as for type 2 diabetes, depression and PILL FOR KIDNEY FUNCTION?

  15. The problem is that other than studies conducted at the University Medical Center in Utrecht, The Netherlands, I can find no study (including those you link to) that concludes that K2 prevents arterial calcification. (One study you link to states only that it is a *plausible* hypothesis.) And key people involved in the Utrecht studies are marketing K2 in a very big way (Formed a production company.) Why, after some years, haven’t their claimed findings been duplicated? (Or can someone point to a study where they are actually duplicated?)

    1. Go to this website to find studies:

      For patients on anticoagulation therapy, we recommend them to contact their physician for consultation prior to taking vitamin K2. However, based upon NattoPharma documentation, population studies (see e.g. The Rotterdam study) and traditional uses of natto meals, supplementation in the range below 45 µg represents no safety issue for such patients.

      So fare no cases has found place where k2 (very important “k2” and not “k1”. in any way damages patients taking anticoagulant medicine. Saw an interview were that was stated by a leading researcher..

    2. Good point…the Utrecht researchers are involved in the marketing of MenaQ7 too and stand to gain, at least in prestige, if the sales take off. It’s what you call a conflicting interest.

    3. Good observation, Jared — but there is a large chunk of information that you are missing called the VKDP, which stands for the vitamin K dependent proteins. They have been researched all over the world. These are enzymes that are activated by vitamin K2; a dozen of them were identified long before the Maastricht (Utrecht?) studies were done.

      One of the VKDP prevents calcium deposits in the arteries, deposits that make plaque more likely to rupture under stress, such as a blood pressure spike. (We all accumulate plaque as we age.) Another VKDP enables calcium and magnesium to be deposited in our bones, building strong bones in kids and preventing osteoporosis in the elderly.

      Nutritionists wanted to believe that vitamin K1 could activate those proteins, (wonder why?) but studies done in the U.S. and elsewhere have shown that it does not do so, even at high dietary intakes. You could take a 5 g K1 supplement to do the job, but a 1 mg K2 supplement will do that job and many others, such as preventing dementia by maintaining the sphingolipid layer that protects all our neurons–oh, yeah, and all the nerves in our spinal cord, and all the motor nerves attached to them.

      All of these studies have been done outside the Netherlands. And this merely scratches the surface of what K2 can do. Aside from cortisol, glutathione and K2 share the title of the most powerful anti-inflammatory natural substances in the world. To hell with resveratrol–I was once stupid enough to buy that stuff!

      You must be wondering why our news outlets have not been trumpeting the amazing benefits of K2 day and night. The truth is that K2 prevents deaths from heart disease better than statin drugs (43% reduction vs. 30% reduction) with none of the severe side effects. This has been known for years, but what would that news have done to statin drugs, the most profitable prescription drug in the world? And which corporations are paying for half the ads on the nightly news–and giving hundred thousand dollar donations to the campaigns of our senators and representatives?

      Big studies like those in the Netherlands are very expensive. Who is going to fund another one? The drug companies, who fund most of the research at American universities? The NIH, where they have to get funding approval from Congress?

      I think you may be getting the picture.

      1. Hi You seem to have an extyensive grasp of the Vitamin K and K2 in context with dietary and health considerations. Please If you could, cite any articles or references that one could use to follow up on your comments especially regarding K2s role in promoting neuron repairing enzymes, and any info you may have or recommend regarding which kinds of K2 (and their typical sources) should be avoided or managed for those who might be concerned about a hereditary predisposition to fomring dangerous blood clots.

  16. Vitamin K2 has made my teeth whiter and more solid appearing now. I used too many antibiotics at one point in my life and also had GERD, corrected by eating a apple prior to bed and correcting my posture. K2 and Vitamin D rock for correcting the appearance of my teeth.

  17. I’m 50 yrs old. I seen on TV where Dr. Oz has recommended Vitamin K2 for good bone health. I have OsteoPenne and found that after running for 4 years, my bones are worse. I’m now on Vitamin D (5,000 mg per day) and need to do weight bearing exercises. I’m going to start right away taking Vitamin K2. I’m seeing a specailist at the end of the month for my bones. Thanks for the good advice.

  18. Does vitamin K2 have any affect on the eyes? The reason I ask, the pressure has been up in mine since I started taking it.

    1. I think K2 may have caused me to develop an atrophic retinal hole. I am myopic and had floaters before, but I only started developing severe floaters and flashes about a week after starting K2. It also gave me high blood pressure and heart palpitations. I was only taking a tiny dose. Too bad, because other than damaging my eyes and maybe my heart, it made me feel great. Scary stuff. I don’t really understand it.

      1. Vitamin D works with the K-2. If you’re having symptoms like that, look into your Vitamin D levels. There’s also a book by Jeff T. Bowles on the miraculous health benefits of high doses of Vitamin D. Look it up on Amazon.

  19. This, I think explains my craving for caviar with all of my pregnancies. Thanks for all of your posts,keep them coming.

  20. I appreciated all of the information on vitamin K2. My doctor had never heard of it! But I had heard from a friend about the benefits for osteoporosis. I had been taking Evista and had bad leg cramps from taking it! So, now I’m trying the vitamin for my osteopenia. Should I quit taking my daily low dose aspirin?? I am 66 years old and am on no medications. Thank you!

  21. Mark, what is your opinion on fermented dairy, legumes, and grains. Can they still be part of a primal diet?

  22. I have severe osteoporosiss; because I work out daily (1hour and a half), the osteo is not visible. Now, I also have lupus. I do not have kidney problems and no hipatitis. Doctors do not say too much about vitamins or herbs. They told me to take calcium with D, but that is all. Would any other vitamin be beneficial for me? I eat the best food; not the most expensive food, but the best. Fresh vegetables, fruits, legums, etc.
    Thank you
    Marika Bodnar

    1. Well Marika, if you believe the research, you should buy Vitamin K2 supplement(try it is not expensive. It is supposed to be vital in keeping the bones strong, working with vitamin D and calcium as a cofactor.
      Do you eat fermented cheeses like camembert, stilton, gouda, mature cheddar and curd cheese? They have lots of natural K2 made by the bacteria in the cheeses. I eat legumes too, but it won’t go down too well on a paleo website!…..and lots of grains, dairy and no meat…and feel in the best of health….better not go on!

    2. Please check out Menacin for Vitamin D, Calcium and Vitamin K2. or visit the facebook group Menacin Natural Vitamin K2 Supplements 😉

  23. Can we consider Vit K4and Vit K7 have same function and same indication
    and as considered menaQ7 and mena K4 are both vit K2

    which you prefer
    and why
    Dr Samir

  24. Does anyone know where one could get a K2 supplement in the MK4 form?

    1. The only MK4 supplements that I know of to recommend, are green pasture’s butter oil, and Thorne’s K2 drops. Thorne also makes a D3/K2 combo.

  25. Have been Paleo for about 2 yrs. (got there on my own b/f knew about Paleo). I was so lean 2 months ago my blood vessels were much too prominent so I decided I needed more fat. About that time, I also discovered K2. With my osteoporosis worsening, I decided to add back raw grass-fed cheese for the fat and K2. My skin has filled out from the added fat and am hopeful the K2 will improve my bone density. Am concerned about the dairy though, but skeptical about adding natto due to lectins in the soybeans and feel the cheese is the lesser of two evils. Also, added a whole body vibration machine to my regimen for the bone density. Thoughts on natto? May try homemade sauerkraut for it’s K2.

  26. I first learned about vitamin K2 in an Osteoporosis forum. Many on the forum take both forms of vitam K2, MK-4 and MK -7. I have been using MK-4 for a few weeks now for my bones and teeth. Funny thing is I notice that my skin has improved and the plaque on the underside of my bottom teeth is much less. I’m hoping it will help further with my teeth as I have suffered with periodontal disease for many years.

    I am on a modified Paleo diet. Grass fed products are not readily available where I live so I can’t eat totally that way plus I’m on a retired fixed income and it will only go so far. Therefore, I use some supplements.

    I’m 69 years old and still kicking and wanting to learn and improve my life. It’s never too late, right? The Paleo diet is the best one I’ve found to help me enjoy eating. I have Celiac disease and feel fortunate that Paleo is the perfect solution to my dietary needs. There are lots of good books and recipes out there. No need to feel deprived!

  27. I seen the question about kidneys -if K2 is ok –I have stage 4 renal failure–on no meds anymore for my kidneys-been taking D3 for over 1yr an it made big difference–plus I did take antibiotics alot for kidney infections -so much that it has given me —slow gut snydrum–plus I had that plura infection of the gut (i know i spelled it wrong) the dr. put me on triple antibiotics–I took myself off an got on –DGL–&–MASTIC GUM—an got retested an it was all cleared up-I stopped after 1month on these an the belly pain came back in full force–that;s when they found the -slow-gut–so I put myself back on the mastic gum & DGL—after few days noticed big difference so I am taking them forever—I added K2 because I was getting alot of chest tightness -stress test came out ok-but yet they now say the stress test really doesn’t tell the right stuff for woman-because we have trouble with our smaller arteries –to where men have with the larger arteries an thats what shows up are the larger ones not the smaller–an I take 200mg a day of K2–an seem to be fine the chest stuff seems to stopped –I take it because it helps clear the calcium deposits out of the veins –smaller ones to an that was what I was worried about being a woman at age 58—I had a total hysto when I was 34yrs old an already went through menopause -I take no estrogen-so the K2 will benifit the bones—-but I need to know if the K2 will harm the kidneys? I felt safe to take it because I am not on any meds other than a blood-pressure pill an only 5mg at that–I didn’t take any but the BP started to get high 149/105—the top always higher so they put me on a small dose—now this was before I started K2–I’m waiting to see if the BP stays down I will slowly remove the BP med-an keep on the K2 -plus I have been on Vde 5000everday–seems the kidney eats up D3 the kidney drs had me on meds of D3-50,000 for months than I asked if I could take it as a vitamin instead of thier pill an I could so the 5,000 seems to keep my levels at a normal range—-if you could answer me –at my e-mail—[email protected]—-I thank you very much—-there is alot more health things if you like to know ask an I will fill you in on a more private e-mail—tksxo

    1. Hi. I know this is an old post Just wondering how u got on with the k2. I am atage 3 ckd and from my research it seems k2 would be a good supplement to add.

  28. I read that k2 from Natto can dissolve calcifications. I have pain from calcification on the right shoulder bone and it’s tearing at the Tendon on the top of the shoulder. I’ve recently had surgery on the left shoulder to remove the calcification. HOW MUCH TIME does it take to start dissolvingcalcifications?

  29. I reently started taking K2 after finding out I have hypercalcemia which is not related to the parathyroid as my PTH came back normal from blood test.
    How much K2 should I take, I also have high blood pressure, taking lisinopril with water pill combination. I do not feel bad at this time, just worried about the calcium level in my blood which is above normal. i have an appt with an endocrin in April, HELP!

    1. Hi Rana,
      The Dutch researchers recommend up to 180mcg K2 per day with a basic requirement of 45 mcg per day. The MenaQ7 that they use in their experiments is now formulated as a supplement capsule for humans containing 45mcg. The head researcher(forgotten his name) takes 180mcg per day. He also strongly recommends eating a little fermented cheese on a regular basis such as curd cheese or strong mature cheeses.
      Good luck

    2. How have you felt after taking k2? I have high calcium, too, which is not PTH. What did the professional you saw say about this?

  30. Makes me understand now why virtually all ancient cultures (and some still do) incorporated some kind of fermented or cultured food into their diet on a regular basis.

  31. Good article on K2 Mark.
    I am wondering about the conversion of K1 to K2. I listened to a lengthy interview given by the Dutch researcher from Utrecht with Dr Mercola. According to the Dutch researchers, there is plenty of K2 made in the human large intestine by bacteria but only a negligible amount is absorbed into the body. It almost all passes out in the faeces. They say that is why animals often eat their own faeces, like rats and rabbits…to get the vitamin K2 and other digested or fermented nutrients.
    They also say that the conversion of K1 to K2 in the human plasma and cells is very poor, inadequate and unreliable. K2 is readily absorbed however from the small intestine if it is in the food eaten, such as fermented cheese or natto or maybe pasture fed beef etc. How about the K2 produced in cows from their internal bacteria…how does that get into the meat? Is it better absorbed or do they convert the K1 to K2 in their bodies better than humans? Or is the theory that humans cannot adequately convert K1 to K2 wrong? If cows get K1 and K2 from eating grass, why can’t we get it from eating vegetables? These questions were not adequately addressed in the interview.
    I agree that there is a lot of hype and everybody is looking for the next wonder nutrient, superfruit and basically a panacea for all ills! Fashion has taken over. Fiber was the first big thing in the 1960s but you hardly ever hear it mentioned now. Even Atkins is definitely old hat, bless his soul. Every eating fad eventually outstays its welcome I guess and needs to be reinvented.

    All best

  32. Dear All, I buy the Vitamin K2 product named Menacin on
    It is very important to understand that Vitamin K2 in most cases should be taken with Vitamin D. For those interested there is a facebook group named Menacin Natural Vitamin K2 supplements!


  33. Hey Mark if fermented foods are a great source of K’s then how about Kimchi, fermented cabbage. Or Kambucha, the health drink that is naturally fermented?

  34. WHY are there no answers to most of the questions above?? I’m struggling right now and feel like I”m between a rock and a hard place~ Found this site and am really interested in finding out more about K2. I was diagnosed with anti-cardiolipin disease, where my blood produces and antibody that makes my blood clot abnormally. It’s not the same thing as “sticky” blood. But I’ve got several lesions in my brain from these small clots. They put me on Coumadin, but had several nose bleeds that were difficult to stop, so they took me off and put me on aspirin therapy with the advice to stay away from too much Vit K, such as spinach, kale, etc. I am a woman that also worries about osteoporosis and couldn’t take the normal protocols because of jaw issues. I do take Vit D, but do not take dairy of any kind. Any time I start a calcium supplement, I get a kidney stone so I try to stay away from that. I’d love more answers but feel I’ve fallen in to a deep abyss and can’t find my way out~

  35. Hi , I’m trying to help my mother as she has Harderning of the arteries, and takes a blood thiner, Aspirin 100mg or Cardia .
    She also takes Duride 60mg , Lipitor 40mg , Zoton 30mg , Ezetrol 10mg.

    Over the passed 4 weeks ive given her 5,ooo iu of Vitamin D3. Yesterday I stoped giving it to her in fear that ,she will recive to much calcium in her arteries.

    I wanted to put her back on D3 in combo with K2, but , Ive also read not to give her K2 because it will interfear with the blood thinner.

    I am in need of help to weather she can take K2 , with this type of disease. PLEASE HELP ME HELP HER…..Lisa

    1. Hi Lisa,
      You probably found an answer since you posted this a while ago.

      But I found this article, which not only states that K2 should be taken with D3, it also states that K1 can affect blood thinners like Coumadin….but K2 does NOT.

      If this article is incorrect i hope someone else will reply as I too am starting my Dad on the D3/K2 supplements…& he is on Coumadin.

  36. have high PTH levels and calcium in blood. would K2 help lower level.

  37. I am 64 and was diagnosed with rheumatoid arthritis in 2010. I had thyroid cancer in 2007 which resulted in total removal of my thyroid. In the past four years, I have broken four bones, upper rt arm break, lower left leg break, rt wrist and the last one was my left wrist (one wrist bone broke and one of the long bones in my arm split). Surgery was required on both wrist breaks. My orthopedist said it was a difficult surgery due to the weakened condition of my bones. My rheumatologist recommended Forteo. However, my endocrinologist said I was unable to take it due to parathyroid test results (90 – 165). I currently take Areva daily, one Vit D 50,000 mcg monthly,one Enbrel injection weekly, two Cymbalta 60 mg daily, Synthroid 250 mcg daily and Calcium Citrate 3000 mg daily. From doing research on Vit K2, I believe it would help my bone density and strength. I am unsure as to the amount of Vit K2, which supplements and dosages I should take.I read that the Vit K2 and supplements should be taken at the same time with antidepressant medication (Cymbalta). Is this correct? I would appreciate any answers and advice concerning Vit K2 and its benefits for me.

    thank you,
    Mary Duduit

  38. Greetings from pharmchris pharmaceutical, there is a product we need from you, but will like to know if you ship international and will also like to know if you accept credit card. We await your reply as soon as possible so we can send our product list to you, thanks
    Dr Chris

  39. Far too little attention is being placed on the huge role that vitamin K2 plays in dental health. Many people are needlessly suffering costly dental problems due to an undiagnosed vitamin K2 deficiency. Modern diets are nearly always deficient in vitamin K2. Sadly most drug stores do not carry vitamin K2 supplements although many health food stores do.
    Don’t expect the American Dental Association to ever acknowledge the huge role of vitamin K2 with respect to dental health. There is way too much money being made off of crowns, root canals, implants, and costly oral surgery to repair damaged gum tissue.
    Mainstream dentistry has ignored research done way back in the 1920s and 1930s regarding vitamin K2 and the huge role it plays in determining caries susceptibility. It was called “Activator X” back in those days. Ramiel Nagel has websites that are spreading this type of information.

  40. Please could you tell what the RDI / recommended dosage for children of K2 is??! I can’t find it anywhere! Thanks 🙂

  41. Hi everyone, I have a thought on k1 which I would appreciate feedback on. I see that k1 is a fat soluble vitamin but the recommended food sources are low fat leafy greens?! The advice is also to eat the greens with a fat source! I wonder however, if grass fed animals may also be a source of k1? I don’t know if grass actually contains k1? But it is a green plant! The animal eats the grass, we eat the animal and hopefully obtain some k1 in the process? I know we can obtain omega 3 fatty acids from grass fed animals so I just wondered if we could get k1 from them too? Maybe even from algae feeding fish too? Just a thought…..

  42. I recently dissolved a bone spur on the top of my foot at the base of my big toe using a vitamin regimen that included K2. I also soaked in Epsom salt.