Vitamin K
Vitamin K is a group of fat-soluble compounds essential for various bodily functions, notably blood clotting and bone health. It consists of three forms: K1 (phylloquinone), K2 (menaquinone), and K3 (menadione). Vitamin K1 is primarily found in leafy greens like spinach and kale, while K2 is produced by bacteria and found in fermented foods such as cheese and natto, as well as animal products. The body can convert K1 into K2, making a varied diet effective for maintaining adequate levels.
This vitamin plays a critical role in the coagulation process, helping to form blood clots that are vital for healing after injuries. Additionally, Vitamin K supports bone density and mineral health by aiding in the synthesis of proteins necessary for bone strength, such as osteocalcin. While deficiencies are rare, particularly in adults, newborns often receive vitamin K injections shortly after birth due to limited transfer through the placenta. Health experts recommend a daily intake of 90-120 micrograms for adults, which is easily achievable through a balanced diet rich in vitamin K sources. Ongoing research is exploring the potential therapeutic benefits of vitamin K in chronic health conditions like liver failure and Alzheimer's disease.
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Vitamin K
Vitamin K is a collective name given to three classifications of fat-soluble compounds—K1 and K2 and K3—that assist the body in two ways: in the critical process of blood clotting in the immediate aftermath of any invasive injury that punctures the integrity of the skin, and in the long-term process of helping the body’s 206 bones maintain their rich density and mineral health. Vitamin K is seldom taken as a dietary supplement, although it is available as such. Most people receive sufficient levels of vitamin K through following a sensible, balanced diet rich in both leafy vegetables and dairy products. Natural vitamin K deficiencies are rare. Cutting-edge research, however, has begun to look into vitamin K as a possible treatment for a range of long-term debilitating conditions, most prominently liver failure, arterial congestion, and Alzheimer's disease.
Background
Vitamin K1, also known as phytonadione or phylloquinone, is the most common class of vitamin K. It is naturally occurring and readily available in a variety of leafy vegetables, among them spinach, broccoli, kale, collards, and cauliflower. It is also found in a variety of herbs and spices, such as basil, oregano, cilantro, sage, and black pepper, and in vegetable oils. In addition, fibrous fruits can provide vitamin K, including kiwi, blueberries, prunes, and grapes. When K1 enters the body through eating, it is immediately absorbed by the liver until traumatic injury necessitates blood clotting at which point the liver will dispense the vitamin.
Vitamin K2, or menaquinone, on the other hand, occurs in the body and in nature; it is produced by bacterial action during the fermentation process in the production of cheese, milk, soy, yogurt, and natto. It can also found in some other foods, including liver, eggs, and meat. The body’s own bacterial system can actually convert K1 into K2 through bacterial processes in the colon. K2 is secured in the body most easily through a diet rich in meat and in dairy products. Copious research has emphasized that consumers looking to bolster their vitamin K intake should give preference to grass-fed rather than grain-fed fowl and animals in selecting a source for meat and dairy. Once ingested, K2 is absorbed into the blood vessels rather than into the liver; it is then distributed into tissue and bones where it provides critical support for the development and maintenance of bones and teeth.
Little is known to date on K3, also known as menadione. A synthetic vitamin version of it has been investigated as a potential treatment for prostate cancer, although it has an alarming rate of toxicity.
Vitamin K was first isolated and defined by Danish-born biochemist Henrik Dam (1895–1976) during an extensive research investigation conducted in laboratories in Freiburg, Germany, into the dynamics of metabolism using a regimen of feeding chickens a cholesterol-free diet. When the experimental chicks began bleeding uncontrollably, Dam and his team first isolated the vitamin necessary to cause clotting. Dam went on to define more exactly the role of vitamin K in blood clotting, for which he shared the Nobel Prize in Medicine in 1943. Indeed, the moniker vitamin K is an abbreviation for the German word for clotting, koagulation.
Overview
Vitamin K is known largely as a kind of first responder to any traumatic skin-site injury. It is important to distinguish blood clots from blood clotting. Blood clots form in arteries because of gradual accumulations of plaque and over time can cause serious congestion and inhibit blood flow, representing a significant danger should they become dislodged and free-flow through the body’s blood system. Blood clotting, on the other hand, is a complex operation known as coagulation in which an open wound is layered over with an initially sticky protective jelly-like covering that will eventually solidify into a scab. Blood clotting is an essential process in the body’s recovery from invasive wounding. Blood seeping from the wound is converted by the action of more than a dozen proteins into a heavy liquid that will in time cause the wound to stop bleeding, a condition known as hemostasis.
Vitamin K is crucial to the body’s wound recovery process. Most people, of course, take the process of coagulation for granted because naturally occurring vitamin K deficiencies are so rare. The exception is in newborns. Because vitamin K cannot be transported from the placenta to the fetus, doctors are quick to inject newborns with a single shot of vitamin K almost immediately after birth, more than sufficient until the body can begin to produce its own supplies through diet within several weeks.
Vitamin K is also critical in bone and teeth system support. Despite being widely perceived as stable and inert objects that give the body critical shape and definition, bones are actually tissue, living and changing, constantly taking in and replacing nutrients, only one of which calcium. Bones especially need protein called osteocalcin that helps determine bone density, synthesized by the bones chemically in a process known as carboxylation. That process is dependent on vitamin K for efficient operation. The demineralization of bones as the body ages is a critical concern. A deficiency of vitamin K can make bones vulnerable to the risk of fracture. The hips, given their crucial role in body motion and movements, are particularly susceptible. In addition, low levels of vitamin K can contribute to joint pain, low-level arthritis, and in the most severe cases osteoporosis.
The Food and Nutrition Board of the Institute of Medicine recommends 90–120 micrograms of vitamin K daily for adults over 18, female and male. Most diets more than cover that amount. A single cup of kale, for instance, can contain more than a 470 micrograms of vitamin K.
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