Does Vitamin K Thin Your Blood or Thicken It?

A large drainer filled with brussels sprouts.
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Vitamin K is sometimes also known as the "clotting vitamin" as it aids in and is necessary for blood coagulation. This vitamin, however, does not thicken or thin the blood, although it can adversely affect blood thinners because it helps your blood to clot. Easily found in a range of different foods, vitamin K is a fat-soluble vitamin, so your body will store it for future use.

Bodily Functions

In the body, vitamin K helps your blood to clot. In some cases, particularly for the elderly, it also has an important role in maintaining strong, healthy bones. Vitamin K will reduce the likelihood of abnormal bleeding or bleeding in association with certain diseases or conditions, such as extended antibiotic use or liver diseases. As an aid in blood clotting, vitamin K works with both coagulation and anticoagulation proteins.

Vitamin K Deficiency

Vitamin K deficiency is rare because it is found in a wide range of foods. But it can still occur if you have been taking anticoagulants for a long period of time or if you have a pre-existing condition of poor vitamin K absorption. Signs of a vitamin K deficiency include abnormal bleeding and problems with blood clotting. The most obvious of these are nose bleeds, heavy menstrual cycles and bruising. More severe symptoms include blood in your urine and bleeding within your brain.

Suggested vitamin K intakes range between 75 and 120 micrograms per day per person, for adults and adolescents, depending on gender and if women are pregnant or breastfeeding. For children and infants, a range of 2 to 60 micrograms is suggested, depending on age. In all cases, a vitamin K injection is given to newborns at birth as they are frequently at risk for a vitamin K deficiency.

Vitamin K Sources

Vitamin K is most commonly found in leafy green vegetables. Common foods include kale, spinach and dark green lettuces. Cruciferous vegetables, such as broccoli and brussels sprouts, are also excellent sources of vitamin K. In general, the darker green the vegetable, the more vitamin K it contains due to chlorophyll, which provides the green coloring and vitamin K in plants.