Definition of Vitamin K:

Vitamin K is a fat-soluble vitamin that plays an important role in blood clotting. The body can store fat-soluble vitamins in fatty tissue.

Function:

Vitamin K is known as the clotting vitamin, because without it blood would not clot. Some studies indicate that it helps in maintaining strong bones in the elderly.

Food Sources:

Vitamin K is found in cabbage, cauliflower, spinach and other green leafy vegetables, cereals, soybeans, and other vegetables. Vitamin K is also made by the bacteria that line the gastrointestinal tract.

Side Effects:

Vitamin K deficiency is very rare. It occurs when the body can't properly absorb the vitamin from the intestinal tract. Vitamin K deficiency can also occur after long-term treatment with antibiotics.

Individuals with vitamin K deficiency are usually more likely to have bruising and bleeding.

Recommendations:

Specific recommendations depend on age, gender, and other factors (such as pregnancy). The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for vitamin K:

Infants

• 0 - 6 months: 2.0 micrograms per day (mcg/day)
• 7 - 12 months: 2.5 mcg/day

Children

• 1 - 3 years: 30 mcg/day
• 4 - 8 years: 55 mcg/day
• 9 - 13 years: 60 mcg/day

Adolescents and Adults

• Males and females age 14 - 18: 75 mcg/day
• Males and females age 19 and older: 90 mcg/day

If you take warfarin (a blood thinner), you should know that vitamin K or foods containing vitamin K can affect how the drug works. Ask your health care provider how much vitamin K or vitamin K-containing foods you should consume.