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Vitamin K

Vitamin K is a fat-soluble vitamin that is required in very small amounts from the diet and is important for blood clotting.

Vitamin K is essential for creating the proteins that help the blood to clot. It is also very important for increasing the mineral content in the bones (which increases bone strength) as well as for the creation of new cells in the body. There are different, naturally occurring sub-types of Vitamin K: Vitamin K1, which is found in plants and Vitamin K2, which is made by bacteria in the gut. Small amounts of this bacterial form of Vitamin K are absorbed into the body and when a person is taking antibiotic medications, these bacteria are killed and the risk of Vitamin K deficiency increases. Very little Vitamin K is stored by the body; small amounts of this vitamin are deposited in the liver and in the bones, but this amount is only enough to supply the body's needs for a few days. In many countries, newborn babies are routinely given Vitamin K injections because they are at risk of brain haemorrhages (bleeding) during the first few months of life. These injections are necessary because babies generally do not get a large amount of Vitamin K from the diet, as human breast milk contains only small amounts of this vitamin. Overdoses of Vitamin K cause flushing, shortness of breath, chest pains, heart failure and even death.


Always consult your Health Professional to advise you on dosages and any possible medical interactions. Vitamin K may be recommended for the following conditions:

· Excessive bleeding caused by deficiency of this vitamin.

· Prevention of bleeding in newborn babies.

· Gastrointestinal problems that decrease the absorption of Vitamin K, such as obstructions in the bile duct, cystic fibrosis, sprue, Crohn's disease, colitis and medications that reduce the absorption of this vitamin, such as antibiotics.


A deficiency of Vitamin K can cause easy bruising, increased bleeding times (due to poor blood clotting) and an increased tendency to bleed. Inadequate dietary Vitamin K can also increase the progression of diseases like osteoporosis and atherosclerosis.


Rich sources of Vitamin K include broccoli, Brussels sprouts, cabbage, cauliflower, kale, spinach and soybeans. Other sources of Vitamin K include lettuce, pork, liver, egg yolk, safflower oil, alfalfa, blackstrap molasses, yoghurt, canola oil, olive oil and soybean oil. Small amounts of fat are required for the absorption of Vitamin K from food.


The recommended dietary allowance (RDA) for Vitamin K is 80 mg per day for adult males and 65 mg per day for adult females. See your health care professional for advice about the correct dosage for you.

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