For anyone who knows me well, this might be humorous because since high school my nickname has been K2. Take my initials (KK), double them up and you get K2. Usually associated with the mountain or snowboard company, K2 has been a neat little moniker to go by. Then recently I came across vitamin K2. I have always known about vitamin K but didn’t know about the various forms of it or the powerful role they played in health. After doing some investigation, I think it’s my new favorite and it’s not just due to the name…

Vitamin K

Vitamin K is a group of fat soluble vitamins that are primarily responsible for blood coagulation and metabolism in bone and other tissues. The two main vitamers are K1 and K2. K2 has two main subtypes, MK4 and MK7.

(Here we see Vitamin K1 followed by two subtypes of K2: MK4 & MK7)
Vitamin K1 (phylloquinone), found in high amounts in green leafy vegetables, is a major player in blood coagulation. Vitamin K2 (menaquinone) is highly active in bone and tissue metabolism. Vitamin K2 has two major subtypes, MK4 and MK7. As a group, Vitamin K is now considered one of the most important (and often severely depeleted) nutrients in the human body. Although discovered in the 1920’s, it has remained relatively unknown for most of nutritional history. Now K is widely understood as a major player in health and longevity, influencing some vital biological processes…
Blood clotting
Vascular repair
Prevention of vascular calcification
Bone metabolism (repair and strengthening)
Cell proliferation and signal transduction

Look at these actions of vitamin K in context with several big health ailments present in today’s society. Cardiovascular disease, osteoporosis and brain generation diseases are three major issues plaguing the developed world. If we are majorly deficient in Vitamin K2 it might be playing a powerful role in the progression of these conditions.

Where can we get it? Here’s the tricky part. The human body makes MK4 from Vitamin K1 and bacteria in the intestines make MK7 if populated by good bacteria. Unfortunately, the conversion to these subtypes is less than adequate in most people, particularly those who have used antibiotics. Before you head down to the health food to grab your K2 in a bottle let’s look toward nature’s bountiful cabinet…

Food sources of Vitamin K1
Think dark, leafy greens and the skins of fruits and vegetables. Open up the link below for the full USDA food chart.

Vitamin K Food Chart

Food Sources of Vitamin K2
Considered to be the more important version of vitamin K, K2 and it’s main subtypes are found in several foods with the highest concentrations typically found in animal foods. As always, strive to obtain quality sources of animal food whenever possible. Healthy animals eating natural diets produce healthy food.

Vitamin K2 with % as MK-4

1103.4 (0% MK-4)
Goose Liver Paste
369.0 (100% MK-4)
Hard Cheeses
76.3 (6% MK-4)
Soft Cheeses
56.5 (6.5% MK-4)
Egg Yolk (Netherlands)
32.1 (98% MK-4)
Goose Leg
31.0 (100% MK-4)
Curd Cheeses
24.8 (1.6% MK-4)
Egg Yolk (United States)
15.5 (100% MK-4)
15.0 (100% MK-4)
Chicken Liver
14.1 (100% MK-4)
9.0 (100% MK-4)
Chicken Breast
8.9 (100% MK-4)
Chicken Leg
8.5 (100% MK-4)
Ground Beef (Medium Fat)
8.1 (100% MK-4)
5.6 (100% MK-4)
Calf Liver
5.0 (100% MK-4)
4.8 (8% MK-4)
Whole Milk
1.0 (100% MK-4)
2% Milk
0.5 (100% MK-4)
0.5 (100% MK-4)
0.4 (100% MK-4)
Egg White
0.4 (100% MK-4)
Skim Milk
Fat-Free Meats

Courtesy of

Vitamin K2 MK7
It is found in the highest quantity in raw dairy. If you live in California you can get it pretty easy, just make sure it is from a quality source. Raw milk needs to be from healthy, grass-fed & finished cows. Do not drink raw milk from cows that aren’t raised well and/or only grass-fed. Check out for resources near you. Soy natto is also a highly concentrated source of MK-7, look for non GMO soy that has been fermented traditionally. Liver, as it always seems with every vitamin we lack, is a great source as well.

Although all types of K are important, more and more evidence points to the role of Vitamin K2, particularly MK4 as a “missing link” in the human health chain. This is not something that you need to rush out and take a supplement for just yet but keep K2 in mind and keep foods rich in vitamin K (particularly K2) in your nutritional rotation.

Thanks for reading, have a great K week!

Here’s a couple additional reviews on the new king of vitamins…

Protecting Bone and Arterial Health with vitamin K2 Report from Life Extension

Osteoporosis Part 1 & Osteoporosis 2: The Vitamin K2 Story by Jack Kruse

Vitamin K2, menatetrenone (MK-4) by Stephan Guyenet

On the Trail of the Elusive X-Factor: A Sixty-Two-Year-Old Mystery Finally Solved by Chris Masterjohn