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Vitamin K is needed for proper bone formation and blood clotting. In both cases, vitamin K does this by helping the body transport calcium. Vitamin K is used by doctors when treating an overdose of the drug warfarin. Also, doctors prescribe vitamin K to prevent excessive bleeding in people taking warfarin but requiring surgery.
There is promising preliminary evidence that vitamin K2 (not vitamin K1), may improve a group of blood disorders known as myelodysplastic syndromes, which carry a significantly increased risk of progression to acute myeloid leukemia.
Reliable and relatively consistent scientific data showing a substantial health benefit.
Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
Our proprietary “Star-Rating” system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by the medical community, and whether studies have found them to be effective for other people.
For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
| Used for | Amount | Why |
|---|---|---|
Atherosclerosis (Vitamin K1, for coronary calcification ) | 500 mcg per day of vitamin K1 | In a double-blind trial, supplementing with vitamin K1 for three years appeared to slow the rate of progression of coronary artery calcification in seniors. |
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| Used for | Amount | Why |
|---|---|---|
Celiac Disease and Vitamin K Deficiency | Consult a qualified healthcare practitioner | The malabsorption that occurs in celiac disease can lead to multiple nutritional deficiencies. Supplementing with vitamin K may correct a deficiency. |
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| Used for | Amount | Why |
|---|---|---|
Crohn’s Disease | 80 to 1,000 mcg daily | Taking vitamin K can counteract the deficiency and resulting bone loss that can occur in people with Crohn’s disease. |
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| Used for | Amount | Why |
|---|---|---|
Cystic Fibrosis | 5 mg every three days | The fat malabsorption associated with cystic fibrosis often leads to a deficiency of fat-soluble vitamins, such as vitamin K. Supplementation can help counteract the deficiency. |
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| Used for | Amount | Why |
|---|---|---|
Osteoporosis | 1,000 mcg daily | Vitamin K is needed for bone formation, and supplementing with it may be a way to maintain bone mass. |
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| Used for | Amount | Why |
|---|---|---|
Morning Sickness | Refer to label instructions | Vitamin K and vitamin C, taken together, may provide relief of morning sickness symptoms for some women. |
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| Used for | Amount | Why |
|---|---|---|
Phenylketonuria and Vitamin K Deficiency | Refer to label instructions | People with PKU may be deficient in vitamin K, due to the restricted PKU diet. Supplementing with vitamin K may correct a deficiency. |
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1. Miyazawa K, Nishimaki J, Ohyashiki K, et al. Vitamin K2 therapy for myelodysplastic syndromes (MDS) and post-MDS acute myeloid leukemia: information through a questionnaire survey of multi-center pilot studies in Japan. Leukemia 2000;14:1156–7 [letter].
2. Shea MK, O'Donnell CJ, Hoffmann U, et al. Vitamin K supplementation and progression of coronary artery calcium in older men and women. Am J Clin Nutr 2009;89:1799–807.
3. Connon JJ. Celiac disease. In: Shils ME, Olson JA, Shike M, eds. Modern Nutrition in Health and Disease, 8th ed. Philadelphia: Lea & Febiger, 1994, 1062.
4. Crofton RW, Glover SC, Ewen SWB, et al. Zinc absorption in celiac disease and dermatitis herpetiformis: a test of small intestinal function. Am J Clin Nutr 1983;38:706–12.
5. Solomons NW, Rosenberg IH, Sandstead HH. Zinc nutrition in celiac sprue. Am J Clin Nutr 1976;29:371–5.
6. Rude RK, Olerich M. Magnesium deficiency: possible role in osteoporosis associated with gluten-sensitive enteropathy. Osteoporos Int 1996;6:453–61.
7. Duggan P, O'Brien M, Kiely M, et al. Vitamin K status in patients with Crohn's disease and relationship to bone turnover. Am J Gastroenterol 2004;99:2178–85.
8. Turck D, Michaud L. Cystic fibrosis: nutritional consequences and management. Baillieres Clin Gastroenterol 1998;12:805–22 [review].
9. Lindemans J, Neijens HJ, Kerrebijn KF, Abels J. Vitamin B12 absorption in cystic fibrosis. Acta Paediatr Scand 1984;73:537–40.
10. Gueant JL, Vidailhet M, Pasquet C, et al. Effect of pancreatic extracts on the faecal excretion and on the serum concentration of cobalamin and cobalamin analogues in cystic fibrosis. Clin Chim Acta 1984;137:33–41.
11. Hart JP. Circulating vitamin K1 levels in fractured neck of femur. Lancet 1984;ii:283 [letter].
12. Tamatani M, Morimoto S, Nakajima M, et al. Decreased circulating levels of vitamin K and 25-hydroxyvitamin D in osteopenic elderly men. Metabolism 1998;47:195–9.
13. Feskanich D, Weber P, Willett WC, et al. Vitamin K intake and hip fractures in women: a prospective study. Am J Clin Nutr 1999;69:74–9.
14. Booth SL, Tucker KL, Chen H, et al. Dietary vitamin K intakes are associated with hip fracture but not with bone mineral density in elderly men and women. Am J Clin Nutr 2000;71:1201–8.
15. Knapen MH, Hamulyak K, Vermeer C. The effect of vitamin K supplementation on circulating osteocalcin (Bone Gla protein) and urinary calcium excretion. Ann Intern Med 1989;111:1001–5.
16. Orimo H, Shiraki M, Fujita T, et al. Clinical evaluation of Menatetrenone in the treatment of involutional osteoporosis—a double-blind multicenter comparative study with 1–alpha-hydroxyvitamin D3. J Bone Mineral Res 1992;7(Suppl 1):S122.
17. Iwamoto I, Kosha S, Noguchi S, et al. A longitudinal study of the effect of vitamin K2 on bone mineral density in postmenopausal women a comparative study with vitamin D3 and estrogen–progestin therapy. Maturitas 1999;31:161–64.
18. Shiraki M, Shiraki Y, Aoki C, Miura M. Vitamin K2 (menatetrenone) effectively prevents fractures and sustains lumbar bone mineral density in osteoporosis. J Bone Miner Res 2000;15:515–21.
19. Craciun AM, Wolf J, Knapen MH, et al. Improved bone metabolism in female elite athletes after vitamin K supplementation. Int J Sports Med 1998;19:479–84.
20. Feskanich D, Weber P, Willett WC, et al. Vitamin K intake and hip fractures in women: a prospective study. Am J Clin Nutr 1999;69:74–9.
21. Booth SL, Dallal G, Shea MK, et al. Effect of vitamin K supplementation on bone loss in elderly men and women. J Clin Endocrinol Metab 2008;93:1217–23.
22. Merkel RL. The use of menadione bisulfite and ascorbic acid in the treatment of nausea and vomiting of pregnancy. Am J Obstet Gynecol 1952;64:416–8.
23. Agostoni C, Marangoni F, Riva E, et al. Plasma arachidonic acid and serum thromboxane B2 concentrations in phenylketonuric children negatively correlate with dietary compliance. Prostaglandins Leukot Essent Fatty Acids 1997;56:219–22.
24. Giovannini M, Agostoni C, Biasucci G, et al. Fatty acid metabolism in phenylketonuria. Eur J Pediatr 1996;155 Suppl 1:S132–5.
25. Poge AP, Baumann K, Muller E, et al. Long-chain polyunsaturated fatty acids in plasma and erythrocyte membrane lipids of children with phenylketonuria after controlled linoleic acid intake. J Inherit Metab Dis 1998;21:373–81.
26. Jochum F, Terwolbeck K, Meinhold H, et al. Effects of a low selenium state in patients with phenylketonuria. Acta Paediatr 1997;86:775–7.
27. Kauf E, Seidel J, Winnefeld K, et al. Selenium in phenylketonuria patients. Effects of sodium selenite administration. Med Klin 1997;92 Suppl 3:31–4 [in German].
28. Sierra C, Vilaseca MA, Moyano D, et al. Antioxidant status in hyperphenylalaninemia. Clin Chim Acta 1998;276:1–9.
29. Gropper SS, Naglak MC, Nardella M, et al. Nutrient intakes of adolescents with phenylketonuria and infants and children with maple syrup urine disease on semisynthetic diets. J Am Coll Nutr 1993;12:108–14.
30. Hanley WB, Feigenbaum AS, Clarke JT, et al. Vitamin B12 deficiency in adolescents and young adults with phenylketonuria. Eur J Pediatr 1996;155 Suppl 1:S145–7.
31. Schulpis KH, Platokouki H, Papakonstantinou ED, et al. Haemostatic variables in phenylketonuric children under dietary treatment. J Inherit Metab Dis 1996;19:603–9.
32. Schulpis KH, Platokouki H, Papakonstantinou ED, et al. Haemostatic variables in phenylketonuric children under dietary treatment. J Inherit Metab Dis 1996;19:603–9.
33. Food and Nutrition Board, National Research Council. Recommended Dietary Allowances, 10th ed. Washington, DC: National Academy Press, 1989.
34. Booth SL, Suttie JW. Dietary intake and adequacy of vitamin K. J Nutr 2000;130(1S Suppl):785–8.
35. Booth SL, Webb DR, Peters JC. Assessment of phylloquinone and dihydrophylloquinone dietary intakes among a nationally representative sample of US consumers using 14-day food diaries. J Am Diet Assoc 1999;99:1072–6.
36. Kodaka K, Ujiie T, Ueno T, Saito M. Contents of vitamin K1 and chlorophyll in green vegetables. J Jpn Soc Nutr Food Sci 1986;39:124–6.
37. Booth SL, Centurelli MA. Vitamin K: a practical guide to the dietary management of patients on warfarin. Nutr Rev 1999;57:288–96 [review].
38. Pineo GF, Gallus AS, Hirsh J. Unexpected vitamin K deficiency in hospitalized patients. Can Med Assoc J 1973;109:880–3.
39. Wong DA, Freeman S. Cutaneous allergic reaction to intramuscular vitamin K1. Australas J Dermatol 1999;40:147–52.
Last Review: 05-11-2011
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The information presented in Aisle7 is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires June 2011.
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