Vitamin K, discovered in the mid 1930s, got its letter designation from the German word koagulation because of the vitamin’s first-known role in blood clotting. Blood remains a liquid in your body, even though it is loaded with all sorts of solid material – red and white blood cells, proteins, vitamins, minerals, and fat. But it also can become a solid within seconds when a blood vessel breaks. The ability of blood to clot is dependent on vitamin K. If your body is short on K, your blood clots very slowly which could be life-threatening.
Vitamin K is found in your liver, brain, heart, pancreas, and bone, in addition to other body tissues. Very small amounts circulate in the blood and the vitamin is rapidly used or excreted from the body. Unlike other fat-soluble vitamins that can be stored in the body in large amounts, there is little storage for vitamin K. That is both good and bad. Good in that it is hard to get too much vitamin K and overdoses are rare. Bad in that you need a continuous supply to meet your body’s needs.
Most of our vitamin K comes from food. Green leafy vegetables and broccoli are particularly rich sources as are soybeans, soybean oil, and canola oil. There are smaller amounts in meat, dairy foods, and eggs. Very few foods, like breakfast cereals, are fortified with vitamin K, but some meal replacement shakes and bars have added K. What is unique about this vitamin is that it can be made in the body by the friendly bacteria in your gut. Though the amount of vitamin K you get through this route is unclear, most experts believe that at least some of the body’s requirement is met this way.
There is little need for a vitamin K supplement through the vitamin is often included in daily vitamin and mineral brands. There are a few instances, however, where extra vitamin K is needed. Newborn babies are recommended to receive a one-time dose of vitamin K after birth because placental transport of this nutrient is poor and breast milk is low in K. People who deal with GI disorders such as cystic fibrosis, celiac disease, and ulcerative colitis may not absorb vitamin K properly. The same goes for patients who have had bariatric weight reduction surgery. Research is also focusing on two areas where vitamin K may play a role – bone health and heart disease. Stay tuned for more research to come.
