There are three main K vitamins: K! and K2 are fat-soluble and can be manufactured in the intestinal tract in the presence of certain intestinal flora (bacteria); K3 is produced synthetically for the treatment of pa¬tients who are unable to utilize naturally occurring vitamin K because they lack bile, an enzyme necessary for the absorption of all fat-soluble vitamins.
If yogurt, kefir (a preparation of curdled milk), or acidophilus milk (fermented milk used to change intes¬tinal bacteria) is included in the diet, the body may be able to manufacture sufficient amounts of vitamin K. In addition, unsaturated fatty acids and a low-carbohydrate diet increase the amounts of vitamin K produced by intestinal flora.
Vitamin K is necessary for the formation of pro-thrombin, a chemical required in blood clotting. Vitamin K is involved in a body process, phosphorylation, in which phosphate, when combined with glucose, is passed through the cell membranes and converted into glycogen, a form in which carbohydrates are stored in the body. It is also vital for normal liver functioning and is an important vitality and longevity factor.
Some natural sources of vitamin K are kelp, alfalfa, green plants, and leafy green vegetables. Cow's milk, yogurt, egg yolks, blackstrap molasses, safflower oil, fish-liver oils, and other polyunsaturated oils are other good sources. The most dependable supply is the in¬testinal bacteria.
Vitamin K can be safely used as a preservative to control fermentation in foods. It has no bleaching effect, no unpleasant odor, and when added to naturally colored fruits, helps maintain a stable and effective condition of the food.
Vitamin K is absorbed in the upper intestinal tract with the aid of bile or bile salts and is transported to the liver, where it is essential for synthesis of pro-thrombin and several related proteins involved in the clotting of blood. Vitamin K is stored in very small amounts, and considerable quantities are excreted after administration of therapeutic doses.
Factors interfering with absorption of vitamin K include any obstruction of the bile duct limiting the secretion of fat-emulsifying bile salts; failure of the liver to secrete bile; and dicumarol, an anticoagulant that reduces the activity of prothrombin in the blood plasma.
Rancid fats, radiation, x-rays, aspirin, and industrial air pollution all destroy vitamin K. Excessive use of antibiotics can destroy the intestinal flora. Ingestion of mineral oil will cause rapid excretion of vita¬min K.
The National Research Council states that the abun¬dance of vitamin K in most diets, along with synthesis by the intestinal bacteria, provides adequate intake of vitamin K. The newborn infant needs a daily intake of 1 to 5 milligrams to prevent hemorrhagic disease, which is abnormal bleeding. It is estimated that the average daily intake is between 300 and 500 micro-grams, which is considered an adequate supply of vitamin K.
Therapeutic dosages of vitamin K are often given before and after operations to reduce blood losses. Vitamin K injections are sometimes given to women prior to labor to protect against hemorrhaging.
Abnormal blood clotting can occur in persons tak¬ing anticoagulant drugs and high doses of vitamin K. Excessive doses of synthetic vitamin K can cause toxic reactions because the supplements will build up in the blood. Toxicity brings about a form of anemia that results in an increased breakdown in the red blood cells. In infants, kernicterus, a condition in which yellow pigment infiltrates the spinal cord and brain areas, can result, usually developing during the second to eighth day of life. Heinz bodies, or granules in the red blood cells resulting from damage to the hemo¬globin molecules, are seen in infants suffering from an overdose. Toxicity has occurred when large dosages of synthetic vitamin K were injected into pregnant women. Flushing, sweating, and chest constrictions are symptoms of synthetic vitamin K toxicity. Natural vitamin K is stored in the body and produces no toxic¬ity signs.
Deficiency Effects and Symptoms
Deficiencies of vitamin K usually result from inade¬quate absorption or the body's inability to utilize vita¬min K in the liver. Vitamin K deficiency is common in diseases such as celiac disease (intestinal malabsorption), sprue (malabsorption in adulthood), and colitis, which affect the absorbing mucosa of the small intes¬tine and cause a rapid loss of intestinal contents. In such cases, intravenous administration of vitamin K may be needed.
In a deficiency, a condition of hypoprothrombinemia can occur, causing blood-clotting time to be greatly or even indefinitely prolonged. A deficiency can cause hemorrhages in any part of the body, including the brain, spinal cord, and intestinal tract. A vitamin K deficiency can cause miscarriages and nosebleeds and can also be a factor in cellular disease and diarrhea.
Beneficial Effect on Ailments
Vitamin K is necessary to promote blood clotting, espe¬cially when jaundice is present. It is administered to heart patients who are using anticoagulant drugs to thin the consistency of their blood. Carefully mea¬sured doses of vitamin K are given to these patients to raise the prothrombin level slightly while not allow¬ing it to completely counteract the effect of the anticoagulant.
Vitamin K has proved beneficial in reducing the blood flow during prolonged menstruation; clots either diminish or disappear. It has often lessened or re¬lieved menstrual cramps.
Vitamin K is frequently used with vitamin C in the prevention and improvement of hemorrhages in various parts of the eye. Vitamin K is also used to prevent hemorrhaging following gallbladder operation to prevent cerebral palsy.