Vitamin K #FoodFacts

This vitamin totally fascinated me when I was in school studying to become a Holistic Nutritionist. Why? Because I had no idea how crucial of a role it played in directing calcium safely into our bones! And THIS is a big thing to be aware of when we are starting to age and if we start to supplement… ESPECIALLY with everyone supplementing SO much with Vitamin D these days!…

But wait a minute, I thought we were talking about Vitamin K? What doest Vitamin D have to do with that? Well, if you’ve been following the previous #FoodFacts posts, you may already have an idea, but if not, you’re definitely going to want to continue reading…



There are 3 main types of Vitamin K. Phylloquinone (K1) generally found in plant founds, Menaquinone (K2) generally found in animal foods but can also be found in some fermented foods and can be produced in our gut (!) and lastly there’s Menadione (K3) which is the synthetic molecule of Vitamin K.

This fat soluble vitamin is absorbed in the the upper small intestine with the help of bile/bile salts and pancreatic juices (yum!!). This means that if you are someone that has lowered or decreased bile secretion, you *may* have issues with optimal absorption.

#FunFact: Our gut bacteria can actually make K2 which is why it was originally thought that we didn’t need to supplement with it! However, the amount produced in our gut is different for everyone. Healthy gut bacteria is crucial for this! If you have taken antibiotics or have suffered from gut infections/food sensitivities, you may not have enough K2 production. K2 is not stored in the body, so it needs to be consumed regularly or supplemented.


However, with that being said, there are few other factors when it comes to absorption. High intake of Vitamin E or calcium can also interfere with absorption, especially if supplementing, and antibiotics can diminish the bacterial flora which decreases natural K2 production. Rancid oils, x-rays, radiation, aspirin, air pollution and freezing food can also destroy Vitamin K.


Vitamin K is fat-soluble meaning when it is ingested, it is absorbed with other fats and can be stored in the body’s fatty tissue. For optimal absorption, consider consuming your fat-soluble vitamins with other healthy fats- either through diet or supplementation.


As mentioned briefly above, a key role that Vitamin K plays is guiding calcium safely into the bones which helps to strengthen bone mineral density and reduce fractures, which is SUPER important, especially as we age, to help prevent diseases such as osteoporosis.

But beyond that, it also prevents calcium from building up in our vessels. Why is THIS important? Having adequate amounts of Vitamin K could help to prevent, reduce or even remove dangerous calcification (calcium plaque) in the arteries – particularly in the coronary (heart) arteries. With this being said, it’s good to know that this vitamin is crucial in blood clotting – which is great when you have a cut or nose bleed but can cause issues when those clots interfere with heart health!

*please remember and keep in mind that all of this information is for educational purposes only and is not to be treated as medical advice. Please consult your health practitioners before trying any new supplements or health routines.*


The main important functions and uses are:

    • Blood clotting
    • Optimal heart health
    • Guiding calcium safely into the bones
    • Preventing coronary calcification

#FunFact: Phylloquinone (K1) was discovered in Denmark and named vitamin K for the Danish word koagulation.

WHAT TO LOOK FOR in supplements

As we’ve learned there are 2 main types of naturally occurring Vitamin K; Phylloquinone (K1) which is primarily found in green veggies and Menaquinone (K2) which can be produced in our gut and found in animal/some fermented foods.

However, Menadione, is an entirely synthetic molecule of vitamin K, also known as K3. This version is used therapeutically and is twice the activity of natural occurring K. It’s important to note that this is also the only version known for causing toxicity. This version can help people who have bile secretion issues, although, sometimes a change in diet can also assist with bile secretion so it just depends on where your body is at.

When looking for supplements I personally would look for a liquid K2 version in a dark glass bottle as it is a fat-soluble vitamin and so it can be better absorbed that way. Another great way to get K2 is to find your Vitamin D3 with K2 already add. Generally, being deficient in K1 is very rare so it isn’t common to supplement- it also very easy to get from diet! However, so can K2 🙂 it just depends on how your body uses and absorbs these vitamins.


If you saw my earlier post on Vitamin D, you know that K2 + D3 are a hot supplemental item! This is because Vitamin D increases the absorption of calcium from the intestines, however, once it makes it into our bloodstream, vitamin D has no control over where calcium goes. This is where K2 comes in. K2 helps bind calcium to the bone and works with D3 to improve calcium absorption directly into our bones- NOT our arteries! (which yes, does happen- especially when people improperly supplement!)

Vitamin D also increases the bodies need for K2 so if you are supplementing with Vitamin D (which, as we know, pretty much everyone should be!), then your body most likely needs K2 as well. See the food source list below to find out how you can feed your gut flora to increase natural production!

Vitamin K should not be taken routinely without the ability to monitor its effects on blood clotting.


Technically, you shouldn’t be deficient in Vitamin K unless you have an absorption/secretion issue. Why? Because our body can naturally produce K2, given the right circumstances, AND it’s pretty easy to get from diet- no matter what your dietary restrictions are!

Anything that helps to feed & foster health production of intestinal bacterial flora is great for K2 production! That means fibrous foods (the prebiotics – essentially “fertilizer” for our microbiome), certain fermented foods & beverages (the probiotics for our gut) and lots of healthy healing fats.

Dietary Sources of K1:

      • Dark seasonal leafy greens, ideally steamed – especially collards, spinach, beet greens, kale and chard
      • Seasonal green veggies – such as asparagus, green onions, avocados..
      • Cruciferous veggies – like Brussels sprouts, cabbage, broccoli..
      • Alfalfa, seaweed, kelp & micro greens
      • Black Strap Molasses

Dietary Sources of K2

      • Fermented soybeans (nattō especially)
      • Fermented, unpasteurized local dairy products like quality soft cheeses (jarlsberg & gouda are good choices), cottage cheese,  yogurt, kefir, heavy cream, etc.
      • Ethically sourced liver – especially fermented fish liver oils (yum!!)
      • Free-range egg yolks (keep them runny if possible!)
      • Grass-fed butter or ghee
      • Wild game meat
Deficiency’s can be hard to spot at times as they are generally associated with other symptoms/deficiencies. Because it is essential in heart health, works closely with Vitamin D and essential for bone/skin/tissue health as well as blood clotting, a few signs could be:
      • osteoporosis or similar bone diseases
      • infertility
      • varicose veins, stretch marks or wrinkles – especially at an earlier age
      • bleeding/ hemorrhage or poor quality wound healing (ex: bleeds excessively, nose bleeds, easily bruised, potentially blood in stools/urine..
      • dental cavities/ chalk like teeth or poor dental health
      • Crohn’s or diabetes
      • heart diseases or heart issues
      • kidney stones.

Toxicity is not very common at all and has only been associated with K3 (menadione), which is the synthetic or artificially produced form of vitamin K. When toxicity does occur, it manifests with signs of:

      • jaundice (yellow discoloration of the eyes and skin)
      • hyperbilirubinemia (build up of bilirubin in the blood which causes jaundice)
      • hemolytic anemia (disorder in which red blood cells are destroyed faster than they can be made)
      • and kernicterus in infants (type of brain damage that can result from high levels of bilirubin in a baby’s blood)

With love,
Heidi MacAulay, R.H.N.
“Eat more plants. Do more yoga. Read more books.”
Learn more about me, my credentials or how to work with me here!

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