Vitamin K is being touted these days in beauty creams, but what is it exactly? Essential to healthy blood and clotting, as well as to bone health, vitamin K is our body's single greatest defense against bleeding problems. Lynn Laboranti, MS and RD, spoke to the Wellness Advisor about vitamin K.
What is Vitamin K?
Lynn Laboranti: Vitamin K is a fat-soluble vitamin that is required for normal coagulation of blood. It is referred to as the anti-hemorrhagic vitamin since it is necessary for synthesis of four of the thirteen cofactors involved in blood clotting. There are two naturally occurring forms of vitamin K, vitamin K1 and vitamin K2, which are found in green plants and microorganisms, respectively. Synthetic vitamin K, or menadione, is water-soluble and is destroyed to a great degree with cooking. Menadione is converted to vitamin K2 in the body.
Why is Vitamin K important?
Laboranti: Vitamin K has a very important role in the coagulation of blood. It is critical for the synthesis of blood clotting factors in the liver. Vitamin K also has hemostatic activity and is used to treat anticoagulant-induced prothrombin deficiency. In addition, vitamin K may also aid in maintaining bone health. Vitamin K helps certain proteins bind calcium and is required for proper bone mineralization. Recent study results provide further evidence that a healthy diet containing adequate vitamin K may help to assure adequate bone density and protect against osteoporosis and hip fractures in postmenopausal women. There are vitamin K-dependent proteins found in bone. Osteocalcin is a regulator of bone mineralization and high circulating concentrations of osteocalcin have been associated with low bone mineral density and increased risk for hip fractures.
How much Vitamin K do I need to get everyday and what is the best way to get it?
Laboranti: For healthy adults, females should consume at least 90 micrograms a day of vitamin K, even throughout pregnancy and lactation. Healthy adult males should consume 120 mcg a day of vitamin K. No tolerable upper intake level has been established for vitamin K since there is lack of data on adverse effects at higher amounts. You can meet your daily requirements for vitamin K by consuming green leafy vegetables on a consistent basis. Other sources of vitamin K are dry soybeans, lentils, vegetable oils, chicken egg yolk, and butter.
For those who may not consume these foods regularly, a daily multivitamin would help meet your vitamin K requirements. It is important to note that individuals who are on anticoagulant therapy, should not consume large amounts of vitamin K in their diet or vitamin K supplements. Vitamin K is antagonistic to the effects of anticoagulants which can result in increased bleeding.
I hear Vitamin K touted as an ingredient in a lot of beauty products--does it help with appearance?
Laboranti: There is some research on vitamin K to improve the skin. In particular, topical application of vitamin K cream has shown to reduce bruising and discoloration after laser treatment for purpura--purplish discolorations in the skin produced by small bleeding vessels near the surface of the skin. More research on vitamin K for improved appearance of skin is warranted.