Vitamin K is important for blood clotting and bone health. It may also prevent dangerous buildup of calcium in tissues, organs, and blood vessels of people with or at risk of certain conditions like kidney disease, heart disease, and diabetes.
Vitamin K1 (phylloquinone) is dietary vitamin K. Sources include green leafy vegetables (especially collards, spinach, and salad greens), soy beans, and vegetable oils. Vitamin K2 refers to a group of compounds (menaquinones) synthesized by bacteria in the intestinal tract; the amount synthesized does not satisfy the vitamin K requirement.
Excessive intake of vitamin K rarely occurs. Excess doses (>1,000 times the requirement) can promote thrombogenesis and hemolysis. Vitamin K toxicity is rare but is most common in formula-fed infants. High doses of vitamin K can worsen the clotting problems caused by severe liver disease.
Vitamin K toxicity can occur only with type K3 that leads to haemolytic anemia by inhibiting the glutathione function that may lead to accumulation of reactive oxygen species. This may cause rupture of red blood cells membrane due to oxidative stress and thus lead to haemolytic anemia, jaundice and liver damage.
Hypervitaminosis K
