Vitamin K is required by the body for posttranslational modification of certain proteins. These proteins are required for blood coagulation and involved in metabolism pathways in bone and other tissue. Also known as phylloquinone or phytomenadione, and also referred to medically as phytonadione, Vitamin K2 is produced by bacteria in the large intestine, and like other liposoluble vitamins, namely A, D, and E, is stored in the fat tissue of the human body.
Vitamin K is essential for:
- allowing your blood to clot normally
- helping to protect your bones from fracture
- helping to prevent postmenopausal bone loss
- helping to prevent calcification of your arteries
- providing possible protection against liver and prostate cancer
- regulation of inflammatory response
- support of brain and nervous system structure
Vitamin K Deficiency
The recommended daily allowance (RDA) for Vitamin K is 80 mg for adult males and 65 mg for adult females. The symptoms of vitamin K deficiency are problems blood clotting or bleeding, which can include easy bruising, blood in the urine, prolonged clotting times, hemorrhaging, and anemia. A second set of vitamin K deficiency-related symptoms involves bone problems, such as loss of bone (osteopenia), decrease in bone mineral density (osteoporosis), and fractures. Another consequence of vitamin K deficiency involves hardening of the arteries or problems with heart valve function.
Vitamin K deficiency is rare unless the intestines are damaged and unable to absorb the vitamin, or, if there is decreased production by normal flora, which is often caused by broad spectrum antibiotic use.
Foods Rich in Vitamin K
Here are a list of foods rich in vitamin K:
- brussels sprouts
- swiss chard
- green beans
- green peas
Vitamin K: Risk of Overdose
There is no known toxicity associated with vitamin K, but allergic reaction from supplementation has been scientifically documented. In light of this no tolerable upper level (UL) has been officially set. However, a synthetic from of vitamin K (K3) called Menadione, has been banned from over the counter sale by the FDA because high doses cause hemolytic anemia and cytotoxicity in liver cells.