K2: How to Get This Important Vitamin by Joan Kent, PhD
As you may know, vitamin K1 helps blood clot. K1 deficiency is rare. It’s found in plant foods, mostly leafy greens: kale, collard greens, spinach, turnip greens, broccoli, and Brussels sprouts.
Vitamin K2 is important for completely different functions. K2 helps to:
• prevent cardiovascular disease
• form strong bones and teeth
• prevent osteoporosis
• prevent kidney stones
• promote healthy skin and prevent wrinkles
• prevent cavities, and more.
K2 is found primarily in animal products and fermented foods. (To keep this brief, we’ll skip the subtypes of K2.) Food sources of K2 are listed below.
While K1 and K2 are similar in structure, they work so differently. Is there any connection between the two? And if so, what is it?
Let’s Start with How K2 Prevents Cardiovascular Disease
K2 promotes the deposit of calcium in bones and teeth, especially when it’s combined with vitamin D3. It does that by activating osteocalcin and other proteins related to skeletal growth and bone formation.
K2 prevents the deposit of calcium in soft tissues, where we don’t want it. That’s how it helps to prevent calcification of arteries, formation of atherosclerotic plaques inside arteries, and cardiovascular disease.
Why Are Animal Products the Primary K2 Source?
The human body can convert K1 to K2 but only to a limited degree. Animals are better at the conversion process.
Here’s the connection between the two vitamins. Animals get their K1 from eating grasses and other plants. They convert that K1 to K2.
Cheese and butter are sometimes listed as sources of K2, but that’s not enough to provide K2. Ideally, we need to choose grass-fed cheese or butter because of the K1/K2 connection.
Fermented cheeses — such as Jarlsberg, Edam, Gouda, cheddar, Brie, and blue — contain vitamin K2 that’s formed by the bacteria used during their production. Cheddar and Brie are particularly high in K2 due to the types of bacteria used.
Butter and ghee (clarified butter) from grass-fed cows are excellent sources of K2.
Egg yolks are another good source of K2 — ideally from free-range chickens, which eat grasses.
Dark chicken meat and beef are good K2 sources, but again from grass-fed animals.
Two other K2 sources are goose liver and chicken liver. My recommendation would be to eat free-range versions of those, as well.
What Should Vegans Eat to Get K2?
Natto from fermented soy is one of the few non-animal sources of vitamin K2, and has high K2 content.
Sauerkraut is another K2 source. Use real, fermented sauerkraut.
The label should list only 2 ingredients: cabbage and salt. (Possibly water, too.) Avoid a product with vinegar. That would actually be pickled cabbage, not sauerkraut — no matter what the label calls it. Fermentation is key.
Kimchi, made from fermented vegetables, also contains K2.
Because we can convert K1 to K2 to some degree, be sure to eat plenty of leafy green vegetables to get lots of K1 — and for many other health reasons.
If you have any blood clotting problems, check with your doctor to be sure eating leafy green veggies is a good option for you.
Would you like other simple food tips? Perfect! That’s what I do. Just visit www.LastResortNutrition.com and grab your free Empowered Eating Consult. Discover how easy it is to make small shifts that yield big results!
Brought to you by Dr. Joan Kent, best-selling author of Stronger Than Sugar: 7 Simple Steps to Defeat Sugar Addiction, Lift Your Mood, and Transform Your Health.