Vitamin K

Vitamin K refers to a group of fat-soluble vitamins that are involved in blood coagulation, bone metabolism, and regulation of calcium levels in the blood.

The body needs vitamin K to produce prothrombin, a protein and coagulation factor that is important in blood coagulation and bone metabolism. People taking blood-thinning medications such as warfarin or Coumadin should not start consuming additional vitamin K without first asking a doctor.

Deficiency is rare, but in severe cases it can increase clotting time, causing bleeding and excessive bleeding.

Vitamin K1 or phylloquinone comes from plants. It is the main type of dietary vitamin K that less source of vitamin A is vitamin K2 or menaquinone, which occurs in some animal-based and fermented foods.

Uses

Phylloquinone, also known as vitamin K1, is found in plants. When people eat it, bacteria in the large intestine convert it into vitamin K2, the depot form. It is absorbed in the small intestine and stored in adipose tissue and liver.

Without vitamin K, the body cannot produce prothrombin, a clotting factor necessary for blood clotting and bone metabolism.

Most Americans are not at risk of vitamin K deficiency. It is more likely to affect newborns and those with malapsorption problems, for example, due to short bowel syndrome, cystic fibrosis, celiac disease, or ulcerative colitis.

Newborns normally take injections of vitamin K to protect them from bleeding from the skull, which can be fatal.

The recommended adequate intake for vitamin K depends on age and gender. Women aged 19 and over should consume 90 micrograms (mcg) per day, and men should take 120 mcg.

Benefits

Vitamin K benefits the body in several ways.

Bone health

There appears to be a correlation between low vitamin K intake and osteoporosis.

Several studies have suggested that vitamin K supports the maintenance of strong bones, improves bone density and reduces the risk of fractures. However, research has not confirmed this.

Cognitive health

Increased levels of vitamin K in the blood have been associated with improved episodic memory in older adults.

In one study, healthy individuals over the age of 70 with the highest vitamin K1 levels had the highest verbal episodic memory performance.

Heart health

Vitamin K can help lower blood pressure by preventing mineralization where minerals build up in the arteries. This allows the heart to freely pump blood around the body.

Mineralization naturally occurs with age and is an important risk factor for heart disease. Adequate vitamin K intake has also been shown to reduce the risk of stroke.