This is a common question I get, so I thought I'd bring you the facts with some new and interesting research:
What is vitamin K?
Vitamin K is a fat-soluble vitamin that is necessary for blood clotting (which is why it’s given to babies right away), bone building and inflammation control.
You may have heard of the two main types of vitamin K:
- K1 – found in greens and veggies
- K2 – thought to be produced solely by bacteria, but recently discovered that it can be converted from K1 in the body, therefore found in fermented foods (some more than others), grass-fed organ meats, and K1-rich veggies
There has been a lot of research recently on the anti-inflammatory effects of K2, specifically the MK-7 form as it stays active longer and therefore can be supplemented easier.
Vitamin K has been referred to as the “Roto-Rooter" of the blood vessels in Naturopathic medical circles for its ability to keep calcium where is should be and help prevent and reduce heart disease, osteoporosis and cancer.
What Foods Are Good Sources of Vitamin K?
- K1 – green veggies like kale, spinach, Brussels sprouts and broccoli (see a full list at the bottom of this page from World’s Healthiest Foods)
- K2 – grass-fed organ meats. Natto is highest, though miso and tempeh have some. According to Dr. Mercola, yogurt has “almost no vitamin K.” Gouda and Brie cheeses however can have up to 75 mcg per ounce, also according to Dr. Mercola. Dr. Cannell also reports evidence that “K2 content in peripheral organs is higher after vitamin K1 ingestion than K2 ingestion.”
Do I Need to Supplement Vitamin K (a note to those on blood thinners)?
Likely not if you have a healthy diet (grass-fed meat/butter, greens daily, fermented foods). Also, if you are taking any type of blood thinner, like Coumadin, you have to be really careful about the amount of vitamin K you are getting. I have heard so many people say that they “can’t eat greens” because they’re on Warfarin/Coumadin. Well, in my opinion, that is completely ridiculous. Of course you can eat greens, but when you are on a blood thinner, you have to be really careful and plan and monitor any diet or supplement changes with your doctor. The key for anyone on a blood thinner looking to develop healthier diets and lifestyles is consistency. You can’t have 3 servings of vitamin K-rich veggies one day and no vitamin K-rich foods the next day. Blood thinners work to reduce the clotting action of vitamin K, so if you are not monitoring your INR and eating or supplementing inconsistently, you could be getting too much (blood too thin) or too little (blood too thick/clotty) of your medication which can significantly increase risk of stroke.
So, bottom line, diet should be your ultimate multivitamin/mineral. But when you can't, or if you need therapeutic doses due to already having a condition that implies a vitamin K deficiency, supplementation should be discussed with your health care provider.
Mercola J. New Study Shows Evidence That Vitamin K2 Positively Impacts Inflammation. www.mercola.com, October 12, 2013.