Vitamin K is lipid soluble and may therefore be stored in fat. It plays a role in blood clotting and in enhancing the calcium-binding properties of the bones. Vitamin K exists in two natural forms. The majority of vitamin K is produced by microorganisms (bacteria) that synthesize it from food in the intestine. The synthesized vitamin is called menaquinone or vitamin K2. It can also be found in certain foods, like green vegetables, in the form of phytomenadione or vitamin K1
What does vitamin K do?
Vitamin K1 plays a direct role in the blood clotting process while vitamin K2 is active in the calcification of tissues.
Adequate Intake *(AI) of Vitamin K:
Source: Food and Nutrition Board, Institute of Medicine, USA, Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc, 2002. This data reflects a consensus between Canadian and U.S, authorities.
*Lacking sufficient scientific evidence, authorities have established adequate intakes (AIs) rather than recommended dietary allowances (RDAs). Adequate vitamin K intake is based on average intakes in North Americans in good health.
**1 µg = 1 microgram, or 1 millionth of a gram.
A relatively limited number of foods contribute significantly to phytomenadione intake. Vitamin K is sensitive to light, alkaline conditions, and air, but is not destroyed by cooking heat.
Food Sources for Vitamin K:
Source: DRIs, Dietary reference intakes, 2002, p. 257.
It is extremely rare to observe clinically significant vitamin K deficiency within the population since this vitamin is essentially produced by the body.
However it may occur in individuals who have:
NOTE: At birth, it takes the body one week to produce vitamin K. Newborns therefore receive a vitamin K supplement at birth to promote clotting in case of bleeding and prevent the risk of hemorrhage.
Signs of vitamin K deficiency:
Even at very high doses, vitamin K causes no notable adverse reactions.
Signs of excess vitamin K:
Natural health products or vitamin supplements:
Taking vitamin K supplements may reduce the anticoagulant effect of certain medications while vitamin K absorption is decreased by:
Speak with your pharmacist if you plan to take vitamin K supplements. Your pharmacist can help you choose the solution that’s best for you based on your health and any drugs you take.
Vitamin K, Phytomenadione, Vitamin K1, Blood clotting vitamin, Menaquinone , Vitamin K2