Vitamin K is a fat-soluble vitamin that helps control blood coagulation and anti-coagulation. The body can store vitamin K in fatty tissue, though it rarely is stored at toxic levels. Vitamin K is produced by plants as phylloquinones and by bacteria as menaquinones. According to the World's Healthiest Foods, up to 90 percent of dietary vitamin K comes from plant sources. The remaining vitamin K is produced by bacteria in your intestines.
Function
Vitamin K primarily functions as a blood coagulation monitor. Adequate amounts of vitamin K allow for optimal blood-clotting ability. Vitamin K can help prevent fractures and bone loss in post menopausal women. Adequate intake of vitamin K can prevent the risk of arterial hardening. Vitamin K has also show the ability to help prevent free-radical damage, regulate the inflammatory process and increase the health of the central nervous system.
Deficiency
According to Medline Plus, vitamin K deficiency is rare but can occur with major blood loss or long-term antibiotic treatment. Deficiencies can increase the risk of bone weakness and fractures. Low vitamin K can increase bleeding in your gums, digestive tract, nose and urinary tract. It can also cause heavy bleeding during the menstrual cycle. Deficiencies may cause bruising, prolonged clotting time, internal hemorrhaging and anemia. In older women, deficiencies may increase the risk of osteoporosis.
Toxicity
Dietary vitamin K rarely causes overdoses. Supplementing certain forms vitamin K will increase the risk of vitamin toxicity. Menadione is a synthetic form of vitamin K that increases free radicals and damages the kidney and liver. Because of the risks associated with menadione, the FDA no longer permits the menadione form of vitamin K to be sold as a dietary supplement.
Food Sources
Vitamin K is found in green leafy vegetables. Plant sources of vitamin K include spinach, green leaf lettuce, kale, collard greens, beet greens, turnip greens, mustard greens and dandelion greens. Moderate plant sources include green onion, Brussels sprouts, broccoli, parsley and asparagus. Animal sources include meats and eggs.
Drug Interactions
Diets high in vitamin K should be adjusted and monitored by those on blood-thinning medication. Coumadin and other blood thinners increase clotting time, and high levels of vitamin K can compromise the medications' desired clotting ability. Recommended intake of vitamin K follows the RDA recommendations of 120 micrograms for men and 90 micrograms for women. Cholesterol-lowering drugs and antibiotics can also decrease the absorption of vitamin K. Antibiotics decrease the amount of intestinal bacteria that synthesize vitamin K. Over-the-counter medications such as aspirin and antacids may also reduce vitamin K absorption.
Member Comments