Vitamin K2 might be the next vitamin D3, they are similar
- Both vitamins were initially confused with its lesser form (D3 by D2, K2 by K1)
- Both vitamins appear to influence health in large number of ways
- Both vitamins in the body are about 1/10 that of a century ago
- Need very little of both vitamins <= 1 milligram)
- Vitamin K2 understanding and research is about 20 years behind that of Vitamin D3
One of the reasons: No simple blood test for K2 as of Dec 2012
Overview of K1 vs K2 controversy (Aug 2012)
|K1||K2 M-4||K2 M-7|
|Source||Green leafy vegetables||Cheese, animal fat, egg yoke, |
natto, free-range lard
|Bone||Slight ability to activate osteocalcin||Strong ability to build strong bones|
|Duration in body||Days||Hours||days|
|Recycled in body||Yes - so not need much|
deficiency is uncommon
|Ability to activate MGP and reduced arterial plaque||Slight||Strong|
|Amount needed for health||90 ug|| not specified 90 -300 -1000ug|
Japanese have 45,000 ug
Vitamin K1 = phylloquinone = phytomenadione = phytonadione
(memory aid: K1 = P = Plant)
Vitamin K2 = menaquinone = menatetrenone
Both K1 and K2 promote blood clotting (Koagulations vitamin, from German)
Controversy, but appears that
- K2 better than K1 at building bones
- Coumadin (warfarin) blocks all forms of vitamin K
- 2007 – vitamin K2 is the most bioavailable, bioactive and longest lasting form of vitamin K
- Extensive interaction between Vitamin K, Vitamin D, and Calcium (bones, prostate, arteries, . . . )
Vitamin K emerging issues – Jan 2011 (click to see PDF)
- In Japan, a common therapy for osteoporosis is vitamin K supplementation in the form of menaquinone-4.
- The standard dose of menaquinone-4 that is employed is 45,000ug/d, and it is used as a drug therapy rather than as a nutritional supplement.
- This dosage is 450-fold higher than the current US dietary
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Vitamin K2 and the Calcium Paradox – 2012 book review by VitaminDWiki
Interview of author by Mercola Dec 2012
CLICK HERE for transcript with highlights by VitaminDWiki
Highlight from interview" 100 ug of vitamin K2 PER 1000 IU of vitamin D
Some suppliers of large amounts of K2
- Thorne liquid 10 drops = 1000 mcg K2 (MK4) and 5,000 IU vitamin D3
125 servings (of 10 drops) per $22 bottle
- Bone restore with K2 Life Extension (improved)
4 capsules: Vitamin D3 1000 IU (low) ; MK-7 200 mcg, Ca 700 mg, Magnesium (citrate) 300 mg, Zinc 2 mg, Manganese 1 mg, Silicon 5 mg, Boron 3 mg
- Natures Life Vitamin K-2 Menatetrenone — 5000 mcg - 60 Tablets $17
Comment by admin of VitaminDWiki: taking this about once every 4 days with vitamin D, and hoping that the half life of K2 is long enough
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- 2012 Vitamin k and the nervous system: an overview of its actions -full text on-line
- 2012 Vitamin K-antagonists create arterial plaque. Vermeer full text on-line
- 2012 The role of vitamin k in soft-tissue calcification. -full text on-line Vermeer
- 2012 Vitamin k status and vascular calcification: evidence from observational and clinical studies -full text on-line
- 2012 Vitamin K, an emerging nutrient in brain function
- 2012 Vitamin K: the effect on health beyond coagulation - an overview -PDF at bottom of this page (Vermeer)
- 2011 Conclusion: A low intake of vitamin K1, but not K2, was associated with an increased risk of hip fractures.
This is the opposite of current belief
- 2011 olive oil helped
- 2011 Bone quality in diabetics improved with vitamin K2
- 2010 Vitamin K2: a novel therapy for osteoporosis
- 2011 Vitamin K, bone fractures, and vascular calcifications in chronic kidney disease: an important but poorly studied relationship.
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Green Medical Info has the following list of medical references for Vitamin K (1&2?)
Cumulative Knowledge = approximately strength of evidence
Meta-Analysis = 20; Human Study = 10, Human: Case Study = 3; Animal: Transgenic = 2 Animal In Vitro, Review, or Commentary = 1
Example: 50 = 2 Meta-Analysis & 1 Human Study
A few articles at Green Medical Information on Vitamin K (K1 and K2)
- Menaquinone-7, a form of vitamin K2, may prevent age-related bone loss.
- Dietary intake of menaquinone is associated with a reduced risk of coronary heart disease, cardiac mortality, aortic calcification and all-cause mortality.
- Vitamin K may reduce the risk for artherosclerosis.
- Vitamin K may be effective in preventing and treating osteoporosis and arterial calcification.
- Evidence shows that deficiency of Vit. K may contribute to the development of cardiovascular plaque (increased intima media thickness)
and supplementation may reverse or forestall the process of calcification.
- Vitamin K supplementation inhibits the progression of coronary artery calcification in older men and women.
- High dietary menaquinone (Vitamin K2) intake is associated with reduced coronary calcification.
- Vitamin K(2) may represent a new agent for the treatment of rheumatoid arthritis.
- Vitamin K supplementation in postmenopausal women wih osteopenia appears to protect against bone fractures and cancers.
- Vitamin K1 and K2 exhibit anti-fracture activity.
- The intake of natto, an excellent source of vitamin K2, may reduce bone fracture risk.
- Menaquinone-7 (vitamin K2) supplementation increases osteocalcin carboxylation associated
- High-dose vitamin K supplementation reduces fracture incidence in postmenopausal women.
- Vitamin K2 (MK-4) may be beneficial in the maintenance of bone health in postmenopausal women.
- Supplementation with phytonadione (Vitamin K1) and menaquinone (Vitamin K2) , particularly menaquinone-4, is associated with increased BMD and reduced fracture incidence.
- vitamin Vitamin (2) works synergistically with alendronate on improving both osteocalcin carboxylation and BMD of femoral neck in postmenopausal women with osteoporosis.
- Low vitamin K status is associated with abnormal cartilage, bone mineralizations and osteoarthritis in the hand and knee.
- Vitamin K3 induces programmed cell death in breast cancer cells.
- Vitamin K2 inhibits cell growth in cholangiocellular carcinoma cell lines.
- Pharmacological Actions : Apoptotic, Cell cycle arrest
- Supplementation of vitamin K antagonists with 100 mcg of vitamin K improves stability of anticoagulant therapy and reduces side effects.
- High dietary intake of vitamin K rich foods is associated with a lower risk of coronary artery disease.
- Research indicates that vitamin K2 intake reduces coronary heart disease events.
- A high vitamin K2 (menaquinone) intake reduces the incidence of coronary heart disease.
- Vitamins K2 and D3 have a protective effect on prednisolone-induced loss of bone mineral density in the lumbar spine.
- High dose vitamin K is efficacious in correcting vitamin K deficiency in cystic fibrosis.
- Vitamin K2 may improve bone quality in type 2 diabetes.
- Low levels of vitamin D and K are highly prevalent and independent of overall malnutrition in the institutionalized elderly.
- Vitamin K2 induces cell cycle arrest and programmed cell death in gastric cancer cell lines.
- Levels of menaquinone-7 and vitamin D are lower in those wtih hip fracture, indicating they may have a role in fracture prevention.
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Vitamins D and K as pleiotropic nutrients:
clinical importance to the skeletal and cardiovascular systems and preliminary evidence for synergy.
Altern Med Rev. 2010 Sep;15(3):199-222. Kidd PM. University of California, Berkeley, USA. dockidd at dockidd.com
CLICK HERE for excellent full text and PDF
See also VitaminDWiki
- Increased Vitamin K2 reduces the problems of excess Calcium – Nov 2013
- Vitamin K-2 (180 ug MK-7) helped both bone density and strength – RCT March 2013
- Synergism between Vitamin D, Vitamin K-2, and Vitamin A: Masterjohn – Sept 2013
- Hip fractures greatly reduced by sunshine, vitamin D, and Vitamin K – meta-analysis Sept 2012
- Vitamin K2 is a vitamin D co-factor Dr Colgan, etc.
- Vitamin D – vitamin K – brittle bones – hardened arteries – LEF Sept 2010
- Cholesterol, Vitamins D3 and K2, heart disease, sulfates, LDL, – Masterjohn Interview Jan 2013
- Vitamin A may thwart the ability of vitamin D to reduce risk of osteoporosis – June 2010
- K2 from natto improved bone mineral density – March 2011
- Do not reduce vitamin K if taking warfarin
- Co-factors to take with vitamin D Includes Vitamin K (need to update to specify K2, not K1)
- Vitamin K helps vitamin D build bone – April 2012
- Vitamin K1 reduced hip fracture but Vitamin K2 did not – Aug 2011
- All items in Bone-Health 151 items
- All items in category K2 30 items
- Vitamin K helps vitamin D build bone – April 2012
abstract does not specify K1 vs K2
See on web
- Vitamin K and bone health – need more research Oct 2013
- Effects of vitamin K in postmenopausal women: Mini review Nov 2013
interesting abstract which finishes with MK-4 seems safe even at doses as high as 45mg/day.
- Strong bones recommendation by VitaminDWiki admin - approx 2005
- Mercola video interview of Vermeer 10 parts July 2010
- how Vitamin K (1, 2, or 5) combined with Sorafenib treats Pancreatic Cancer perhaps 20X better than either item by itself
Journal Cell Physiology, 2010, full text on-line
- Vitamin K2 administration is associated with decreased disease activity in patients with rheumatoid arthritis Nov 2012
- Mark' Daily Apple on Vitamin K2 Feb 2009
Extensive description of all of the vitamin K around the world, lack of RDA for K2, etc.
- Phylloquinone and vitamin D status: associations with incident chronic kidney disease in the Framingham Offspring cohort. 2012
Higher K1 associated with an increased risk of incident CKD. - by 2x
- Vitamin K1 intake cuts risk of diabetes in the elderly by 50 percent Natural News Dec 2012
- Coronary artery calcification in Japanese men in Japan and Hawaii. 2007 full text online
The Japanese living in Hawaii (and not eating Natto as much) had 4X more Coronary Artery Calcification. Those in Hawaii also happened to smoke 4X less than those in Japan
- Mercola long article on importance of Vitamin K2 and Vitamin D March 2011
Includes the following charts
- Vitamin K status and cognitive function in healthy older adults Neurobiology of Aging, Sept 2013
Vitamin K1 (not K2) improved 20 minute recall. Details of how much K1 and how much improvement are behind a paywall
- Huge overview of Vitamin K Examine.com; here are just the topic areas covered
Sources and Structure; Sources and Origin; Structure and Properties; Mechanisms and the Vitamin K Cycle; Mechanisms Independent of the Vitamin K Cycle; Recommended Intake; Deficiencies; Supplemental Forms of Vitamin K;
Pharmacology; Absorption; Distribution; Serum; Tissue/Cellular Uptake; Colonic Kinetics and Fermentation; Excretion; Topical Application;
Longevity; Mitochondria; Aging;
Neurology; Mechanisms; Neuroprotection; Neuroinflammation; Cognition; Multiple Sclerosis;
Cardiovascular Health; Cardiac Tissue; Coagulation and Clotting; Calcification;
Interactions with Glucose Metabolism; Insulin; Insulin sensitivity;
Fat Mass and Obesity; Mechanisms;
Skeleton and Bone Metabolism; Mechanisms Independent of the Vitamin K Cycle; Mechanisms via the Vitamin K Cycle (Osteocalcin); Bone Mineral Density; Fractures; Joint Health;
Inflammation and Immunology; Cytokines;
Interactions with Hormones; Sex Hormone Binding Globulin; Testosterone; Cortisol;
Interactions with Organ Systems; Liver; Pancreas; Male Sex Organs;
Interactions with Cancer Metabolism; Mechanisms; Hepatocellular Carcinoma;
Interactions with Aesthetics; Skin;
Interactions with Pregnancy; Requirements (Pregnancy); Requirements (Lactation);
Interactions with Disease States; Cystic Fibrosis; Pseudoxanthoma elasticum;
Nutrient-Nutrient Interactions; Vitamin C; Vitamin D; Vitamin E; Sesamin; Anticoagulants;
Safety and Toxicology; General; Case Studies; Menadione;
Food and drink launches containing vitamin K2 almost double (over 5 years) Food and Bev Sept 2013
new product launches containing vitamin K2 have almost doubled (+183%) globally over the past five years (2008-2012).
vitamin K1 was used in the overwhelming 96% of products, with the remaining 4% containing vitamin K2.
Benefits of Vitamin D - Mercola
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Benefits of Vitamin K - Mercola
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Problems of excess Calcium - Mercola
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Interesting speculation on Vitamin K2 from a June 2011 e-mail
We also know that virtually 100% of people are vitamin K deficient according to Dr. Vermeer who has studied vitamin K and K2 for 30 years.
– – – –
Dr. Vermeer recommends 45 mcg of vitamin K2 daily as a starting point but feels 180 mcg is optimal. He personally takes 360 mcg daily. There is no known adverse affects or toxicity. The 45 mcg of k2 can be achieved with cottage cheese (100 grams of curd cheese provides 45 mcg of vitamin K2). Low fat cottage cheese is comparable to high fat. (Approximately 7/8ths of a cup daily).
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Early humans ate a vitamin K rich diet. Their diet closely resembled that of the Chimpanzee today which is about 40% green leaves. Chimps consume over 200 different varieties of leaves. According to some reports it amounts to a shopping bag full of leaves daily. This represents a tremendous amount of vitamin K1.
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Termites are also an important part of the chimpanzee diet and they are still an important source of food in hunter gather human societies. Termites are rich in vitamin K2.
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Humans do produce vitamin K2 in the gut but it is formed in the large intestine and passes out as waste. This is because absorption of fat soluble vitamins requires choline which only forms in the small intestine. This is why rats eat their own feces as it a rich source of vitamin K2.
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Does the DNA of black humans demand a higher daily intake of K1 and K2 to prevent atherosclerosis than whites when normalizing their vitamin D? Is there a variable vitamin K2 need based on race? The answer appears to be yes in both cases. Since black have some of the earliest human DNA they may require the primitive input of vitamin K/K2.
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My other question pertains to kidney stones. If K2 prevents calcification of arteries, could K2 also prevent accumulation of calcium in the kidneys?
– – – – –
Vitamin K is necessary for the production of a urinary protein involved in kidney function that inhibits the formation of calcium oxalate kidney stones
– – – – –
Much like vitamin D the half life of vitamin K2 varies based on type. MK4 has a half life of about 1 hour, while MK7 has a half life of 3 days. MK7 provides much more stable serum levels.
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Heart Scan Blog 2007 listing of foods with lots of vitamin K2 - including
- MK-7 and MK-8,9,10 come from bacterial fermentation, whether in natto, cheese, or in your intestinal tract;
- MK-4 is naturally synthesized by animals - egg yolks and fermented cheeses
- Natto is the richest source of the MK-7 form
- Coumadin (warfarin) blocks all forms of vitamin K.
Cardiovascular Mortality much worse if lacking Vitamin K2 from MenaQ7.com
The above is their advertisement
Called Natto in Japan and Thau-nao in Thailand this cultured whole bean soy food has a strong, somewhat persistent, unique flavor.
The bacteria, Bacillus subtilis var natto, that culture the cooked soybeans make a sticky, viscous polymer during the 6-12 hours of incubation.
This creates wispy threads evident when the cultured soybeans are pulled apart.
A good source of protein, this robust soyfood adds zest to any grain or noodle dish, soup or sandwich.
A little goes a long way, so what is not intended for use in a day or two may be easily frozen.
Our Natto starter, imported from Japan, has a 6 month or more shelf life.
Natto Starter Kit:
This 11gm packet contains culture directions, recipes, and enough spore to start 3 batches of natto, each making 5 cups or 1.5 pounds.
$3.00 + $3.00 shipping in the US. As of July 2011 the supplier only accepts check of money order, no on-line sales
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Cees Vermeer (64) is Associate Professor of Biochemistry at the Maastricht University and since 10 years also CEO of VitaK, a spin-off company focusing on research on vitamin K and vitamin K-dependent proteins. VitaK employs 14 researchers (PhD, MSc, and BSc) who are all working on a) clinical trials to demonstrate health effects of vitamin K, b) development of new biomarkers based on vitamin K-dependent proteins and c) analysis of K-vitamins in foods and body fluids. Cees Vermeer has been the supervisor of 16 PhD students and is an author in over 300 papers in the international scientific press. VitaK is specialized in bone and cardiovascular health and has a long-standing R&D collaboration with NattoPharma; we have demonstrated the quality and health effects of MenaQ7 in several independent clinical trials and also act as consultant for scientific and regulatory affairs as well as for designing and defending IPR.
Dr. Vermeer studied Biochemistry at Leiden, where he also presented his PhD thesis (1974) on the initiation of protein biosynthesis in E coli. In 1975 Dr. Vermeer was appointed at the Department of Biochemistry of the Universiteit Maastricht, where he has founded the Division on Vitamin K In 1984 he was appointed as an Associate Professor of Biochemistry and Principal Investigator at CARIM. In 1994 Dr. Vermeer was appointed as a temporary adviser of the World Health Organization and in 2001 he received the honorary title of Doctor honoris causa at the University of Medicine and Pharmacy "Iuliu Hatieganu" of the city of Cluj-Napoca, Romania. Moreover, in 2001 Dr. Vermeer founded the company VitaK BV, where he became the first CEO of the company.
Slide show for VitaK from Dec 2010 is attached at the bottom of this page
The following are some of the slides
Cees Vermeer, PhD; Associate Professor of Biochemistry; BioPartner Center Maastricht; c.vermeer at bioch.unimaas.nl
Interesting association of Vitamin K2, Termites, and Latitude
As far as vitamin D goes nobody should be living above 35° latitude in winter.
We are not designed to live above that latitude due to the zenith angle of the sun and low UV.
Chimpanzees eat termites and will even eat termite mound dirt to get the vitamin K2 contained in the soil and we share over 99% of the same DNA.
We also were designed to eat termites (vitamin K2) and these insects do not thrive above that latitude…
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Wonder if the lack of vitamin K2 is perhaps responsible for decrease efficiency of vitamin D production by elderly skin
Lack of Vitamin K2 ==> less blood circulation to skin
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WikiPedia on Vitamin K Deficiency Oct 2011
Average diets are usually not lacking in vitamin K and primary vitamin K deficiency is rare in healthy adults.
Newborn infants are at an increased risk of deficiency.
Other populations with an increased prevalence of vitamin K deficiency include individuals who suffer from liver damage or disease (e.g. alcoholics), people with cystic fibrosis, inflammatory bowel diseases or those who have recently had abdominal surgeries.
Groups that may suffer from secondary vitamin K deficiency include bulimics, those on stringent diets, and those taking anticoagulants.
Other drugs that have been associated with vitamin K deficiency include salicylates, barbiturates, and cefamandole, although the mechanism is still unknown.
There is no difference between the sexes as both males and females are affected equally.
Symptoms of deficiency include heavy menstrual bleeding in women, anemia, bruising, and bleeding of the gums or nose.
They could also have disorders such as coagulopathy.
Osteoporosis and coronary heart disease are strongly associated with lower levels of K2 (menaquinone).
Menaquinone is not inhibited by salicylates as happens with K1, so menaquinone supplementation can alleviate the chronic vitamin K deficiency
caused by long term aspirin use.
2008 long excellent article has the following points
- The authors point out that the benefits of K2 were most pronounced for advanced prostate cancer, and, importantly, that vitamin K1 did not offer any prostate benefits.
- It has been commonly believed that the benefits of vitamin K are limited to its role in blood clotting. Another popular misconception is that vitamins K1 and K2 are simply different forms of the same vitamin – with the same physiological functions.
- However, intake of vitamin K1 had no effect on cardiovascular disease outcomes.
- Foods high in vitamin K2
- Hard cheese, Soft cheese (if grass fed, not grain fed)
- Egg yolk, Butter (grass fed, not grain) , Chicken liver, Salami, Chicken breast, Ground beef
Clinical Trials for "vitamin K" 397 as Dec 2012, many completed
Vitamin K-absorption From Dairy
The Effects of Vitamin K2 Supplementation on the Progression of Coronary Artery Calcification (VitaK-CAC)
Beneficial Effects of Long Term Menaquinone-7: 180 µg menaquinone-7 daily for three years; Bone Loss & Arteriosclerosis
Comparison of Absorption of Vitamin K2: softgel capsules containing 180 µg MK-7 and 750 IU vitamin D3 + 120 µg MK-4
The Effect of Vitamin K2 on Bone Turnover
Misc April 2012
Little had been known about Vitamin K in 2001
Vitamin K Nutrition, Metabolism, and Requirements: Current Concepts and Future Research
Martin J. Shearer 3, martin.shearer at gstt.nhs.uk., Xueyan Fu4, and Sarah L. Booth 4
3Haemostasis Research Unit, Centre for Haemostasis and Thrombosis, Guy’s and St Thomas’ NHS Foundation Trust, and King’s College, London, UK; and
4 Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
Adv Nutr March 2012 Adv Nutr vol. 3: 182-195, 2012
Snip of abstract
In 2001, the US Food and Nutrition Board concluded that there were insufficient data with which to establish a RDA for vitamin K, in large part because of a lack of robust endpoints that reflected adequacy of intake.
Review of Vitamin K2 to reduce probability of artery calcification
Vitamin K Status and Vascular Calcification: Evidence from Observational and Clinical Studies 1,2
M. Kyla Shea 3, kshea at wakehealth.edu. and Rachel M. Holden 4
3 Sticht Center on Aging, Wake Forest School of Medicine, Winston-Salem NC; and
4 Department of Medicine, Queen's University, Kingston, Ontario, Canada
Vascular calcification occurs when calcium accumulates in the intima (associated with atherosclerosis) and/or media layers of the vessel wall. Coronary artery calcification (CAC) reflects the calcium burden within the intima and media of the coronary arteries. In population-based studies, CAC independently predicts cardiovascular disease (CVD) and mortality. A preventive role for vitamin K in vascular calcification has been proposed based on its role in activating matrix Gla protein (MGP), a calcification inhibitor that is expressed in vascular tissue. Although animal and in vitro data support this role of vitamin K, overall data from human studies are inconsistent. The majority of population-based studies have relied on vitamin K intake to measure status. Phylloquinone is the primary dietary form of vitamin K and available supplementation trials, albeit limited, suggest phylloquinone supplementation is relevant to CAC. Yet observational studies have found higher dietary menaquinone, but not phylloquinone, to be associated with less calcification. Vascular calcification is highly prevalent in certain patient populations, especially in those with chronic kidney disease (CKD), and it is plausible vitamin K may contribute to reducing vascular calcification in patients at higher risk. Subclinical vitamin K deficiency has been reported in CKD patients, but studies linking vitamin K status to calcification outcomes in CKD are needed to clarify whether or not improving vitamin K status is associated with improved vascular health in CKD. This review summarizes the available evidence of vitamin K and vascular calcification in population-based studies and clinic-based studies, with a specific focus on CKD patients.
Appears that Vitamin K is needed to prevent bone loss
Vitamin K-Dependent Carboxylation of Osteocalcin: Friend or Foe?
Caren M. Gundberg3, caren.gundberg at yale.edu, Jane B. Lian4, and Sarah L. Booth5
3Orthopaedics and Rehabilitation, Yale School of Medicine, New Haven, CT
4Department of Cell Biology, University of Massachusetts Medical School, Worcester, MA; and
5Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
Adv Nutr March 2012 Adv Nutr vol. 3: 149-157, 2012
Osteocalcin originates from osteoblastic synthesis and is deposited into bone or released into circulation, where it correlates with histological measures of bone formation. The presence of 3 vitamin K-dependent ? carboxyglutamic acid residues is critical for osteocalcin’s structure, which appears to regulate the maturation of bone mineral. In humans, the percentage of the circulating osteocalcin that is not ?-carboxylated (percent ucOC) is used as a biomarker of vitamin K status. In contrast, when ucOC is not corrected for total osteocalcin, the interpretation of this measure is confounded by osteoblastic activity, independent of vitamin K. Observational studies using percent ucOC have led to the conclusion that vitamin K insufficiency leads to age-related bone loss. However, clinical trials do not provide overall support for the suggestion that vitamin K supplementation of the general population will reduce bone loss or fracture risk. More recently, results from in vitro and in vivo studies using animal models indicate that ucOC is an active hormone with a positive role in glucose metabolism. By inference, vitamin K, which decreases ucOC, would have a detrimental effect. However, in humans this hypothesis is not supported by the limited data available, nor is it supported by what has been established regarding osteocalcin chemistry. In summary, the specific function of osteocalcin in bone and glucose metabolism has yet to be elucidated.
Vitamin K2 (MK4, but not MK7 or vitamin K1) has also been shown to prevent bone loss and/or fractures in the following circumstances:
- caused by corticosteroids (e.g., prednisone, dexamethasone, prednisolone), 
- anorexia nervosa, 
- cirrhosis of the liver, 
- postmenopausal osteoporosis, 
- disuse from stroke, 
- Alzheimer's disease, 
- Parkinson disease, 
- primary biliary cirrhosis 
- and leuprolide treatment (for prostate cancer).32
Algecal the company makes a K1 supplement
- Will not hear about K2 because, unlike vitamin D3, it is very pricey $1.5 million per kilogram
$1,500 per gram or $1.50 per milligram or $0.15 per 100 microgram (mcg)
- K2 probably not safe for Pregnant Women
Cardiac dysfunction, Craniofacial abnormalities, Flat nasal bridge, Growth disorders, Learning disorders, Microcephaly. Neural tube defects
See also Vitamin D council
- Dr. Cannell authored a book, The Athletes Edge
in which he recommends 1,000 micrograms of K2 daily (probably if taking > 5,000 IU of vitamin D
- Dr. Cannell on vitamin K2 Nov 2013, behind a $5/month paywall
''One cup of cooked kale has more than 1,000 mcg of vitamin K1. A cup of cooked spinach has more than 800 mcg. And a cup of turnip greens has more than 500 mcg. But that is all vitamin K1.""
There appears to be two sites of conversion of K1 to K2, one in the intestine and another in peripheral tissues.
In Nov 2013 the mechanism by which the body turns vitamin K1 into vitamin K2 was clarified.
It occurs through an intermediary molecule, vitamin K3, which is made in the intestine from vitamin K1.
Low-dose vitamin K2 (MK-4) supplementation for 12 months improves bone metabolism and prevents forearm bone loss in postmenopausal Japanese women May 2013
6 month Random Controlled Trial: Control group with mo K-2 decreased forearm BMD, 1.5-mg K-2 MK-4 has no decrease
K2 stability project announced Oct 2013
Kappa Bioscience had noticed that K2 is lost in the process of making some supplements.
They had looked at 700 products containing K2. Some need 50% more to meet what is stated on the label.