The Facts About Vitamin K

Everyone knows the importance of taking Vitamin C to help strengthen the immune system and avoid scurvy, and that B complex vitamins help to combat stress, but other equally important vitamins are often overlooked. Vitamin K is one of these essential, but often ignored vitamins that perform many vital functions in the body.

There are many food sources that provide ample amounts of vitamin K, which aids in blood clotting and helps prevent bone fracture. Diets rich in broccoli, asparagus, green beans, Romaine lettuce and spinach will provide a person with 100 percent of the recommended daily value of vitamin K. There are also over-the counter options for vitamin K supplements.

There are three types of Vitamin K; two are natural, and one is synthetic. Vitamin K1, also called phylloquinone, is found in plants. Vitamin K2, known as menaquinone, is produced by the friendly bacteria that line the human digestive tract. A third type, vitamin K3, or menadione, is produced synthetically in a laboratory.

According to the United States Department of Agriculture, the foods highest in Vitamin K are kale, collards, spinach, turnip greens, mustard greens, Brussels sprouts, broccoli and onions. All leafy green vegetables contain high amounts of Vitamin K, as do blueberries, plums, black-eyed peas and lentils. Vitamin K is best absorbed when eaten with some amount of fat, such as butter or olive oil.

While there are numerous food sources and supplements readily available that provide vitamin K, too much of the synthetic form of vitamin K, known as menadione(the CAS number is 58-27-5), can lead to toxicity. Menadione can cause cell damage, especially in the kidneys and liver.

Although vitamin K toxicity is possible, it is extremely rare, and its benefits outweigh the risks. According to the National Academy of Sciences, the recommended daily intake for males 19 years and older is 120 micrograms, while females in the same age group have a suggested intake of 90 micrograms. Studies show that people have diets with a daily levels of 340 micrograms per day without causing toxicity. The potential for toxicity is minimal, and the benefits are significant, as vitamin K protects bones from fracture and helps clot blood.