The role of Vitamin K in blood clotting

Introduction

Vitamin K is one type of fat soluble vitamin which has interesting health potential. This potential is that vitamin K has a role in coagulation or known as blood clotting. According to the FAO and WHO, the only clear role of vitamin K in the health sector is to maintain coagulation homeostasis.

Vitamin K in the diet

Byrd-Bredbenner, et al., (2009) stated that about 10% of vitamin K absorbed by the human body daily comes from the synthesis of vitamin K by bacteria in the large intestine, while the rest comes from food sources. The best sources of vitamin K are green leafy vegetables (parsley, green salad, cabbage, and spinach), broccoli, peas, and green beans. Vegetable oils, such as soybeans and canola, are also good sources. Byrd-Bredbenner also states in his book that vitamin K is relatively stable for heat treatment, but that it breaks down when exposed to light. Vitamin K can be sourced from food materials, or synthesized by bacteria, and absorption of vitamin K is influenced by the bioavailability of vitamin K in food ingredients. Mixed diet can contribute 15% of the total intake based on the oil added to food. Other best sources of vitamin K are certain vegetable oils (soy, rapeseed, and olive), which contain 50-200 μg / 100g; other vegetable oils such as peanut oil, corn oil, sunflower oil, and safflower (WHO and FAO UN, 2004). Adequacy of vitamin K for the female group is 90 μg / day; and men is 120 µg / day. Although individuals consume sufficient vitamin K for blood clotting function, it is not known whether increased intake (consumption) of vitamin K might benefit other functions. Vitamin K deficiency or deficiency can occur if there are clinical indications (Byrd-Bredbenner, et al., 2009). Clinical vitamin K deficiency is associated with increased prothrombin time and deficiency may occur in severe cases of bleeding. Savage and Lindenbaum (1983) in Ferland (2012) state that vitamin K deficiency is rare in adults and will experience vitamin K deficiency when gastrointestinal disorders are associated with fat malabsorption (eg bile duct obstruction, inflammatory bowel disease, chronic, cystic pancreatitis. fibrosis) and liver disease. Likewise with hospitalized patients, especially if treated with antibiotics or other drugs (drugs that interfere with vitamin K metabolism), and low food intake and poor nutritional status may also experience an increased risk of vitamin K deficiency.

Vitamin K and Blood Clots

Vitamin K is required for the synthesis of blood clotting factors by the liver and the conversion of preprothrombin to an active blood clotting factor called prothrombin. In brief it can be explained that forming blood clots in the human body requires the participation of vitamin K in both intrinsic and extrinsic bloodclotting pathways. In this process, carbon dioxide (CO2) is added to glutamic acid in preprothrombin, producing prothrombin which contains the amino acids gamma carboxyglutamic or GLA. GLA, a protein that has undergone conversion. All vitamin K dependent proteins (VKDP) contain residual GLA, which is needed to bind calcium and form blood clots. Suttie (2006), the conversion of preprothrombin to prothrombin depends on GLA binding to calcium to participate in clotting reactions. Suttie (2006) adds that in the body, vitamin K is converted into an inactive form after vitamin K is activated by clotting factors. It must then be reactivated for the biological action to take hold. Drugs such as warfarin, which severely inhibits this activation process, act as potent anticoagulants. People taking warfarin to reduce blood clotting should maintain a consistent dietary intake of vitamin K and avoid vitamin K supplements.

References

1. Byrd-Bredbenner C, Beshgetoor D, Moe G, and Berning J. Wardlaw’s Prespectives in Nutrition Eighth edition. McGraw-Hill, New York. 2009.

2. WHO and FAO United Nations. Vitamin and mineral requirements in human nutrition Second edition. WHO Library.2004.

3. Ferland G. Vitamin K in Present Knowledge in Nutrition Tenth Edition. Edited by John W. Erdman Jr, Ian A. Macdonald and Steven H. Zeisel. International Life Sciences Institute. 2012.

4. Suttie JW. Vitamin K. In: Shils ME and others, eds. Modern nutrition in health and disease. 10th ed. Philadelphia: Lippincott Williams & Wilkins; 2006.