Vitamin K2 is a much needed nutrient that plays a great variety of roles in the human body. This vitamin and its actions were not valued or recognized in the past, but promising new research around vitamin K2 is shaping a newly found appreciation for its involvement in certain functions of the human body.
The discovery of Vitamin K
It is interesting to know that the scientist Dr Hendrik Dam discovered vitamin K while he was doing a study on the effects of a fat-free diet on chicks. During the study, the chicks started bleeding uncontrollably under their skins. The reason for this was the fact that they were deficient of vitamin K, which is a fat soluble vitamin that had not been discovered by that time. Dam named the vitamin “koagulationsvitamin” which is a Danish term that means “clotting vitamin” and from there it was known as vitamin K. [1]
What is Vitamin K2 and what are its functions?
Vitamin K is a family of fat soluble vitamins that occur naturally in the form of vitamin K1 (phylloquinone) and vitamin K2 (menaquinone). The K vitamins play a very important role in activating enzymes that change certain proteins to ensure that they bind properly with calcium. The proteins that are dependent on vitamin K1 are concerned with blood clotting while vitamin K2-dependent proteins encourage the transportation of calcium out of soft tissues like veins and arteries and even the skin and into the bones of the skeleton.
Menaquinones can be subdivided into short-chain menaquinones or long chain menaquinones. Long chain menaquinones are currently receiving much attention as they are taken up and transported rapidly in the body and because of the fact that they stay in the body for longer periods of time which prolongs their availability to be absorbed in the body.
Menaquinone-7 (MK-7) is an example of a long chain menaquinone that is present in a traditional Japanese soybean-based product called natto. It is derived from Bacillus subtilis natto. [2][3][4]
Sources of Vitamin K2
Vitamin K2 is mainly produced by intestinal bacteria or by the conversion from dietary vitamin K1. This is ironic because these two mechanisms of K2 production do not provide sufficient amounts of vitamin K2 for optimal health. We need to take in preformed vitamin K2 in our diets to keep healthy. Vitamin K2 is mainly found in meat, egg yolk, liver, butter, hard cheese, soft cheese and natto. [3][4][6][7]
Supplementation of Vitamin K2 is highly advisable and supplements are widely available. Despite the fact that are many food sources of vitamin K2, supplementation is needed to aid the body in optimizing health.
Vitamin K2 deficiency
Vitamin K2 deficiency can have detrimental effects on the body. A shortage of vitamin K2 may cause imbalances in calcium binding as the functions of K2-dependent proteins are hampered when there is a short supply of vitamin K2. This may result in conditions like atherosclerosis, diabetes, Chron’s disease and kidney disease. Dental problems and wrinkles can also be caused by deficiencies of K2. It is speculated that elderly women and new born babies are especially at risk for K2 deficiency. Supplementation could therefore have many benefits for these high risk individuals. It could also be sensible for other people to use K2 supplementations to boost overall health. [2][3][4][5]
The key health benefits of vitamin K2
Vitamin K2 is a versatile vitamin that has many functions the human body of which the most popular is its involvement in blood coagulation. It is needed for the normal clotting of blood, in other words to prevent excessive bleeding. [6]
K2 may furthermore be beneficial for heart health and bone health.
Studies have shown that vitamin K2 could be beneficial in the prevention of heart disease as it is speculated that menaquinone 7 has beneficial effects on age-related artery stiffening. Matrix GLA protein (MGP) is known for its effectiveness in the inhibition of vascular calcification and is dependent on vitamin K2 to perform this function. Furthermore it is possible that vitamin K2 can hamper the progression of atherosclerosis, which is a leading factor in heart disease. [2][5][6][8]
Vitamin K2 may play a large role in bone formation and maintenance. Osteocalcin is the second most abundant protein found in bones and teeth. Vitamin K2 is needed to activate osteocalcin so that it can bind to calcium. This shows how important vitamin K2 is for developing bones and teeth and also how it is needed to keep teeth and bones healthy. [2][9][wc-social-coupon]
Much research is emerging to broaden our understanding of vitamin K2 and its functions and what it can mean for our health. Even though many possibilities of vitamin K2 have already been discovered in the future we may have a greater comprehension of vitamin K2.
- Dam H. The antihemorrhagic vitamin of the chick: occurrence and chemical nature. Nature. 1935; 135:652-653.
- Rhéaume-Bleue K. Vitamin K2 and the calcium paradox. How a little-known vitamin could save your life. Canada: Kate Rhéaume-Bleue; 2012. p. 14, 20,
- Schurgers LJ. Vermeer C. Determination of Phylloquinone and Menaquinones in Food: Effect of Food Matrix on Circulating Vitamin K Concentrations. Haemostasis. 2000; 30:298–307.
- Booth SL. Vitamin K: food composition and dietary intakes. Food & Nutrition Research. 2012; 56: 10.3402/fnr.v56i0.5505. doi:10.3402/fnr.v56i0.5505.
- Vermeer C. γ-Carboxyglutamate-containing proteins and the vitamin K–dependent carboxylase. Biochem J. 1990; 266:625-636.
- Theuwissen E, Teunissen KJ, Spronk HMH, Hamulyák K, Ten Cate H, Shearer MJ et al. Effect of low-dose supplements of menaquinone-7 (vitamin K2) on the stability of oral anticoagulant treatment: dose–response relationship in healthy volunteers. J Thromb Haemost. June 2013; vol. 11(6): 1085–1092.
- Geleijnse JM, Vermeer C, Grobbee DE, Schurgers LJ, Knapen MH, Van der Meer IM et al. Dietary Intake of Menaquinone Is Associated with a Reduced Risk of Coronary Heart Disease: The Rotterdam Study. J. Nutr. November 2004; vol. 134(11): 3100-3105.
- El Asmar MS, Naoum JJ, Arbid EJ. Vitamin K dependent proteins and the role of vitamin K2 in the modulation of vascular calcification: a review. Oman Med J. May 2014; 29(3): 172–177.
- Knapen MHJ, Schurgers LJ, Vermeer C. Vitamin K2 supplementation improves hip bone geometry and bone strength indices in postmenopausal women. Osteoporos Int. 2007; 18: 963-972.