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Vitamin K Improves Bone Mineral Density

When it comes to vitamins, right now, vitamin K is likely my favourite (along with vitamin D). There is so much more to vitamin K than what people think, and the fact that most people don't get enough (since the RDA was set too low to start with) -- compounded with some studies showing many people are deficient in this essential nutrient -- it would be wise to add this supplement to your daily routine.

Calcium supplements are one of the most popular dietary supplements, but mark my words... vitamin K2 is a MANDATORY supplement for anyone taking calcium. If you don't know by now, vitamin K is required to activate certain proteins in the body...and these proteins tell your body what to do with all that dietary & supplemental calcium.

So besides the liver, there are vitamin K-dependant proteins in both the bones, and soft tissues (especially the arteries, but also glands and organs). When these proteins are activated in the presence of vitamin K, the bones suck up calcium, and the arteries prevent calcium from building up in their walls.

Remember mass media making a big deal out of a calcium meta-analysis last year (this CBC article was one of many that covered the story)? The study showed calcium does more harm than good because it causes heart attacks and stroke (which we've known for a long time...but to mass media it was new). What they didn't tell you was that the build-up of calcium in the arteries was not necessarily because people were taking too much calcium, but that they were likely deficient in vitamin K.

Update: the same researchers published a study in April 2011, click HERE for my discussion on the calcium - heart attack link, and HERE for a discussion on what vitamin K deficiency looks like (using patients taking warfarin as an example).

You see, without enough K, your body doesn't know where to put all that calcium, and it can go into soft tissues, like the arteries (called "arterial calcification"), where it's now considered one of the greatest predictors of a heart attack.

Vitamin K2 is now considered one of the best nutrients you can take for bone health because it tells your body to take all that calcium and put it into the bones. This is exactly what this new study showed (link referenced at the end of this post). Basically, the higher your vitamin K intake, the greater your bone density was. My only critique is that it was not a controlled clinical trial, but an observation study based on diet recall.

The story is actually much more complicated than this...so if you'd like me to go into more detail, post a comment and I'll do my best to answer (see the Commenting Policy...really, it's just common sense stuff).

So my conclusion...by getting enough vitamin K, we can kill two birds (osteoporosis and arterial calcification) with one stone.
...and these aren't just any birds, they're huge, menacing, angry birds. Maybe more like fire-breathing dragons.

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Source: Dietary vitamin K associated with bone quantitative ultrasound measurements


  1. Hi Dr. Know,

    I'm one of your blog's "regular" visitors. Thanks for all your amazing posts! I love your sense of humor too. Makes this blog a joy to read...and I'm actually starting to learn about nutrition.

    So my question is, what about kids? Could kids take vitamin K supplements? Is it safe?

    Thanks again!

    Angela P

  2. Thanks for your support and kind words, Angela.

    Yes, vitamin K is great for kids and, IMO, highly recommended for optimal bone development (especially during a period in their lives where they are given the best opportunity to build bone mass and density, which will be drawn upon as they age decades later).

    Below, I've included a link to a study published in 2009 that looked at a dose of 45 mcg/day (of MK-7, a specific form of vitamin K2) and found great bone-related benefits.


    Bye for now.


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  5. Why not vitamin k2 in food, why recommend supplements, esp a fat soluble vitamin. Like the info you are posting but you lose me when you recommend everyone to take supplements. The body doesn't require massive amounts of vitamins. In fat taking fat soluble vitamin supplements is harmful. A diet of whole food including full fat dairy, meat, fish, eggs, veggies, fruit, whole grains, sunshine & excercise will give you all the nutrients your body needs.

    1. Thanks for your email, and I agree with you. Ideally, people should always look to their diets to provide the nutrients they need, and only look to supplements to make up any shortfall. With respect to vitamin K, however, it's tough to get the required amount to adequately activate vitamin K-dependent proteins throughout the body.

      First, the majority of vitamin K in the typical Western diet is K1, which is not absorbed to a great extent. Second, K2 (which does have great absorption) is not found in high amounts in many foods anymore (with the exception of a few foods, especially natto).

      There are numerous reasons for this, but it's likely a combination of multiple factors. For example, most factory farming raises cattle on grains (not a source of K1), not grass (a source of K1). When a cow eats grass, they would normally convert the K1 to K2, and so milk, the cheese made with the milk, and even the meat would have all been much higher in vitamin K in the past than they are now with (predominantly) grain-fed cows. Also, in general, most fermented foods are a reasonable source of K2 (since it's the bacteria that produce K2 in the fermentation process). Since the advent of refrigeration, cultures around the world have relied less on fermentation as a method for food preservation, so we've seen a corresponding decrease in K2 consumption (and a corresponding increase in related diseases). There are possible factors too... but you get the idea. Unless people are cognizant of eating a high-K diet, most likely they will not get enough (and studies show most don't consume nearly enough from food), so supplementation becomes important...maybe not ideal, but definitely important.

      ...in the meantime, everyone should continue to request non-GMO natto from their grocery stores! Let's create the demand.

  6. Still disgree..vitamin k2 is in egg yolk, cheese, milk etc & our wonderful bodies make it in our guts also. When fat soluble vitamins are taken as supplements, they accumulate in the liver and have a toxic effect on the vital organs. The body doesnt need supplements..I think it is just as irresponsible to tout supplementation as it is to market drugs with harmful side effects..if you are a healthy person with a normal gut, supplements will not help you and could harm you.

    1. I agree, vitamin K can be found in egg yolks, cheese, milk, etc., but with our current farming practices, the quantities you’ll find in these foods are insignificant. If you can find free-range or grass-fed animal products, you’ll be able to find vitamin K in greater concentrations in these foods. Also, keep in mind that many fermented foods are also a good source.

      With respect to MK-7, you need at least 45 mcg daily to see about a 40% drop in levels of uncarboxylated osteocalcin, you may presumably need more if looking at MK-4 (due to its pharmacokinetic differences).

      Regarding supplements, the important thing to keep in mind is that it’s the dose that makes the poison. Water will kill you at a certain dose. Supplements taken responsibly are completely fine, and for the vast percentage of the population that don’t consume enough vitamin K from their diet, supplements will be very helpful.

      Should you mega-dose? Certainly not if you’re looking to use vitamin K as a nutrient. Mega-dosing nutrients may be indicated in certain circumstances, but for vitamin K, it’s too early to say, and this has only been studied for MK-4 (using doses of 45,000 mcg/day). And while this was not found to have any acute adverse effects, long-term effects can’t be ruled-out. However, when you’re taking these pharmacological doses, you’re no longer using them as nutrients, but as drugs, and as such, some type of side-effect is likely, and should be expected—at least in some individuals, at some point in time.

      Further, while certain bacterial species in the gut do make K2, many don’t have a healthy gut, so I wouldn’t assume this to be the case in general. It has to be assessed on a case-by-case basis.

  7. The body recycles vitamin k..the body allows vitamin k to function in the gamma~carboxylation of proteins many times decreasing the dietary requirements. Vitamin k deficiency is uncommon in healthy persons Bacteria that normally inhabit the large intestine synthesize vitamin k2, so supplementation is not warranted & probably harmful.

    1. While I’ve agreed with a number of things you’ve said (and it would be helpful if you would comment using a name, even if it’s an alias, so other readers can keep track of who’s saying what), I disagree with the statement that vitamin K deficiency is uncommon. Vitamin K deficiency is more common than most would think. Based on older thinking, yes, vitamin K deficiency is almost non-existent. This is because just about everyone consumes enough K from their diet to adequately carboxylate the vitamin K-dependent clotting factors, which is what we originally thought was vitamin K’s only role (and named "K" for "koagulation"). This is why conventionally-trained medical professionals and even conventional nutrition textbooks will claim vitamin K deficiency doesn’t really exist. However, with newer research, we now know that there are many other vitamin K-dependent proteins in the body (osteocalcin, MGP, nephrocalcin, etc.), and when you start looking at these extra-hepatic tissues and their vitamin-dependent proteins, most people have suboptimal carboxylation of these proteins.

      Now, one may ask, why would nearly 100% of vitamin K-dependent clotting factors be carboxylated, but not a high percentage of the extra-hepatic vitamin K-dependent proteins? Good question. To answer this, we have to consider another newer line of though, the Triage Theory for nutrients. In essence, this theory stipulates that when given a limited amount of a nutrient, the body will prioritize its biochemistry to ensure that pathways needed for immediate survival are satisfied before others. For vitamin K, this means the liver and clotting factors must be fully carboxylated before any excess vitamin K can move on to carboxylate osteocalcin, MGP, etc. Given a limited amount of vitamin K, the body needs to ensure we won’t bleed to death in the next few minutes to hours; it’s not worried about preventing osteoporosis or cardiovascular disease, which would slowly manifest over decades without enough vitamin K).

  8. What type of schooling is required to become a nauropathic doctor in Canada, just curious? Thanks

    1. Four more years, after a prerequisite of an undergrad degree (same as any other licensed medical profession, at least in Canada).


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