What are the Health Benefits of Vitamin K?

What are the Health Benefits of Vitamin K?

What is Vitamin K?

Vitamin K is a group of fat-soluble vitamins consisting of two key forms:

  • Vitamin K1 (phylloquinone)

  • Vitamin K2 (menaquinone) includes menaquinone-4 (MK-4) and menaquinone-7 (MK-7).

The Benefits of Vitamin K

Vitamin K and Cardiovascular Disease

Vitamin K2 is well known for maintaining heart health by preventing the build-up of calcium in your soft tissues, arteries and veins. [1,2]

As a result, Vitamin K2 is especially beneficial for conditions such as atherosclerosis, arterial calcification, and osteoporosis. [1,2]

Over the last 40 years, researchers have discovered that Vitamin K2 is associated with a reduction in the prevalence of cardiovascular mortality. [3]

Vitamin K has been shown to support cardiac output. This is the volume of blood being pumped out of the heart per minute, which enables the body to deliver more oxygen. [4]

Vitamin K and Coagulation

Vitamin K plays a crucial role in supporting healthy blood coagulation, as it carboxylates several clotting proteins in the liver, including clotting factors II (prothrombin), V, VII, and IX. [5]

Vitamin K and Cancer Prevention

 Evidence suggests that Vitamin K inhibits cellular growth in several types of cancer. [6] This includes hepatocellular carcinoma, leukaemia, colorectal, ovarian, pancreatic, and lung cancers. [7] 

Mechanisms include induced apoptosis and cell cycle arrest of cancer cells. [7]

Vitamin K and Osteoporosis

When it comes to bone health, Vitamin K2 regulates bone remodelling, while supporting bone density, mass and integrity, and therefore providing a protective action against bone loss. [8,9]

Vitamin K directs calcium from the arteries back into the bone, which is particularly important for higher-risk groups, such as postmenopausal women.

Research into MK-7, using DXA measurements, has shown significant improvements in reducing the decline in bone mineral content, density, and bone strength, as indicated by Vitamin K. [10]

Vitamin K and Myelin Sheath Function

Healthy nerves require a strong myelin sheath, which is the protective coating that insulates the nerves and conducts the electric signals throughout the entire nervous system. [11]

Vitamin K2 plays a crucial role in the synthesis of sphingolipids, a group of lipids essential for the formation of the myelin sheath and brain cells. [11]

Additionally, Vitamin K-dependent proteins play a crucial role in supporting the health of the central and peripheral nervous systems by promoting mitosis and the growth of neurons and glial cells. [11]

Research suggests that alterations in the metabolism of sphingolipid formation may be linked to inflammation and neurodegenerative disorders, such as Alzheimer’s disease and Parkinson’s disease. [12]

Vitamin K2 and Mitochondrial Health

Vitamin K2 plays a crucial role in the production of cellular energy, helping to maintain normal ATP production. [13]

This suggests that Vitamin K2 may play a role in treating diseases associated with mitochondrial pathologies, such as Parkinson’s disease and amyotrophic lateral sclerosis. [14]

Vitamin K and Blood Glucose Metabolism

Vitamin K is thought to regulate glucose metabolism in insulin resistance and diabetes by modulating osteocalcin and the function of beta cells in the pancreas, as well as by reducing pro-inflammatory cytokines. [15,16]

Vitamin K and Diabetes Type 2

The long-term supplementation of Vitamin K2 has been shown to reduce the risk of developing type 2 diabetes. [17,18]

A large study involving 38,000 men and women, aged 20 to 70, found that 10 µg per day of Vitamin K2 reduced the risk of type 2 diabetes by 7%. [18] 

What Foods Contain Vitamin K?

Plants naturally synthesise Vitamin K1. Foods rich in Vitamin K can be found in high concentrations in leafy green vegetables, such as collard greens, kale, broccoli, and spinach. [9]

Whereas, Vitamin K2 can only be produced by bacteria in fermented foods, such as cheese, curds, and sauerkraut, as well as in animal products like meat, eggs, and liver. [5,9] 

Vitamin K High Foods

The best natural source of foods rich in Vitamin K includes natto, which contains approximately 1,100 mcg of Vitamin K2 in a 100-gram serving.

Natto is a traditional Japanese dish consisting of fermented soybeans. It has a distinctive sticky texture with a somewhat pungent smell, which can make it significantly challenging.

Interestingly, gut bacteria created through the fermentation process can produce many forms of Vitamin K2, the most commonly studied being menaquinone-4 (MK-4) and menaquinone-7 (MK-7).

Other good food sources of Vitamin K2 include goose liver, various organ meats, and soft cheeses like Gouda and Brie, which contain Vitamin K2 in its menaquinone-4 form (MK-4). [5]

Unfortunately, these foods have a short half-life of roughly 4-6 hours, which means you would need to consume these foods every 4-6 hours to maintain optimal K2 (MK-4) levels.

Absorption of Vitamin K

It is essential to note that only 20% of dietary K1 is absorbed, and although it can be converted to K2, the efficacy of this conversion is only between 5% and 25%. [1] 

Studies have compared the body’s ability to absorb Vitamin K, and the results indicate MK-7 is superior when compared to both Vitamin K1 and other forms of K2, such as MK-4. [19,20]

Deficiency of Vitamin K

The inadequate intake of Vitamin K is becoming increasingly common, as the typical Western diet lacks adequate sources of Vitamin K2. [21,22] 

The risk of Vitamin K2 deficiency increases with age, and those who may be using cardiovascular medication and experience bone health issues. [21,22] 

Antibiotics destroy the bacteria or microbiome balance in your gut, thereby potentially affecting your body’s ability to produce Vitamin K. 

The conversion of Vitamin K is also a factor, with humans only converting between 5% and 25% of ingested and absorbed dietary K1 to K2. [23] 

Medications like statin cholesterol-lowering drugs can also inhibit the synthesis of Vitamin K2, potentially accelerating coronary artery calcification and affecting blood glucose levels. [1,22,24] 

Vitamin K Supplements

Since K2 can’t be found in sufficient quantities in the standard Western diet, supplementation becomes necessary. 

With a large number of synthetic formulations of MK-7 on the market, it’s important you choose a non-synthetic Vitamin K supplement that has been naturally fermented from natto (soybean) Bacillus subtilis spores.

Vitamin K and Warfarin

Warfarin and indandione anticoagulants work by inhibiting the conversion of the Vitamin K epoxide back to Vitamin K.

Excessive Vitamin K intake will interfere with the anticoagulant effect of these drugs unless closely monitored, and adverse effects can be rapid and serious. [25,26]

Vitamin K in Pregnancy and Breastfeeding

Although Vitamin K is considered safe for use during pregnancy and breastfeeding, and there have been no adverse events or risks identified in humans, the research is limited or unavailable; therefore, a tolerable upper intake level is not conclusive. [27,28]


 

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+ References

[1] Campbell AW. Vitamin K2 in the prevention of cardiovascular diseases and diabetes. Alternative Therapies. 2017;23(2): 8-10.

[2] Cranenburg ECM, Schurgers LJ, Vermeer C. Vitamin K: the coagulation vitamin that became omnipotent. Thromb Haemost. 2007;98: 120-5.

[3] Geleijinse 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. 2004 Nov;134(11):3100-5. doi: 10.1093/jn/134.11.3100.

[4] McFarlin BK, Henning AL, Venable AS. Oral Consumption of Vitamin K2 for 8 Weeks Associated With Increased Maximal Cardiac Output During Exercise. Altern Ther Health Med. 2017;23(4):26-32.

[5] McCann JC, Ames BN. Vitamin K, an example of triage theory: is micronutrient inadequacy linked to diseases of ageing? Am J Clin Nutr. 2009 Oct;90(4):889-907. doi: 10.3945/ajcn.2009.27930.

[6] Lamson DW, Plaza SM. The anticancer effects of vitamin K. Altern Med Rev. 2003 Aug;8:303–18. PMID: 12946240.

[7] Xv F, Chen J, Duan L, Li S. Research progress on the anticancer effects of vitamin K2 (Review). Oncol Lett. 2018 Jun; 15(6): 8926–8934. doi: 10.3892/ol.2018.8502.

[8] Masterjohn C. Viatmin D toxicity redefined: vitamin K and the molecular mechanism. Medical Hypotheses. 2007;68: 1026-34.

[9] Oregon State University - Linus Pauling Institute [Internet]. Corvallis (OR): Linus Puling Institute; c2002-2018. Vitamin K; 2018.

[10] Knapen MHJ, Drummen NE, Smit E, Vermeer C, Theuwissen E. Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women. Osteoporos Int. 2013;24: 2499-2507.

[11] Ferland G. Vitamin K and the nervous system: an overview of its actions. Adv Nutr. 2012;3(2):204-212. Published 2012 Mar 1. doi:10.3945/an.111.001784

[12] Alisi L, Caro R, De Angelis C, Cafolla A, Caramia F, Cartocci G, et al. The relationships between vitamin K and cognition: a review of current evidence. Front Neurol. 2019 Mar 19;10:239. doi: 10.3389/fneur.2019.00239.

[13] Bhalerao S, Clandinin TR. Vitamin K2 takes charge. Science 2012 Jun 8;336(6036):1241-2. doi: 10.1126/science.1223812.

[14] Vos M, Esposito G, Edirisinghe JN, Vilain S, Haddad DM, Slabbaert JR, et al. Vitamin K2 is a mitochondrial electron carrier that rescues pink1 deficiency. Science. 2012 June 8;336(6086):1306-10. doi: 10.1126/science.1218632.

[15] Choi HJ, Yu J, Choi H, An JH, Kim SW, Park KS, et al. Vitamin K2 supplementation improves insulin sensitivity via osteocalcin metabolism: a placebo-controlled trial. Diabetes Care. 2011 Sep;34(9):e147. doi: 10.2337/dc11-0551.

[16] Juanola-Falgarona M, Salas-Salvado J, Estruch R, Portillo MP, Casas R, Miranda J, et al. Association between dietary phylloquinone intake and peripheral metabolic risk markers related to insulin resistance and diabetes in elderly subjects at high cardiovascular risk. Cardiovasc Diabetol. 2013 Jan 8;12:7. doi: 10.186/1475-2840-12-7.

[17] Yoshida M, Booth SL, Meigs JB, Saltzman E, Jacques PF. Phylloquinone intake, insulin sensitivity , and glycaemic status in men and women. Am J Clin Nutr. 2008 Jul;88(1):210-5. doi: 10.1093/ajcn/88.1.210.

[18] Beulens JWJ, van der ADL, Grobbee DE, Sluijs I, Spikerman AM, van der Schouw YT. Dietary phylloquinone and menaquinones intakes and risk of type 2 diabetes. Diabetes Care. 2010 Aug;33(8):1699-705. doi: 10.2337/dc09-2302.

[19] Schurgers LJ, Teunissen KJ, Hamulyak K, Knapen MH, Vik H, Vermeer C. Vitamin K-containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. Blood. 2007 Apr 15;109(8):3279-83. doi: 10.1182/blood-2006-08-040709.

[20] Sato T, Schurgers LJ, Uenishi K. Comparison of menaquinone-4 and menaquinone-7 bioavailability in healthy women. Nutr J. 2012 Nov 12;11:93. doi: 10.1186/1475-2891-11-93.

[21] Maresz K. Proper calcium use: vitamin K2 as a promoter of bone and cardiovascular health. Integrative Medicine. 2015;14(1): 34-9.

[22] Cranenburg ECM, Schurgers LJ, Vermeer C. Vitamin K: the coagulation vitamin that became omnipotent. Thromb Haemost. 2007;98: 120-5.

[23] Shearer MJ, Fu X, Booth SL. Vitamin K nutrition, metabolism, and requirements: current concepts and future research. Adv Nutr. 2012;3: 182-95.

[24] Okuyama H, Langsjoen PH, Hamazaki T, Ogushi Y, Hama R, Kobayashi T, Uchino H. Statins stimulate atherosclerosis and heart failure: pharmacological mechanisms. Expert Rev Clin Pharmacol. 2015 Mar;8(2):189-99.

[25] Stargrove MB, Treasure J, McKee DL. Herb, nutrient, and drug interactions. St Louis (MO): Mosby Elsevier; 2010. p. 447-57.

[26] Vitamin K. In: Natural Medicines Comprehensive Database [database on the Internet]. Stockton (CA): Therapeutic Research Faculty; 1995-2018 [updated 2018 March 7].

[27] Higdon J. An evidence-based approach to phytochemicals and other dietary factors. New York (NY): Thieme; 2003. p. 90 - 96.

[28] Vitamin K. In: Natural Medicines Comprehensive Database [database on the Internet]. Stockton (CA): Therapeutic Research Faculty; 1995-2018 [updated 2018 March 7; cited 2018 Apr 27].