Vitamin K2

Vitamin K2 (also known as menaquinone) is a fat-soluble compound of the K vitamins that is essential for normal protein synthesis and proper nutrient metabolism in the body.

This element was first isolated by American scientists Binkley and Doisy in 1939 from rotting fishmeal. Biochemists have found that the substance has an antihemorrhagic effect that is different from the functional properties of vitamin K1 previously obtained from alfalfa. The new substance was given the name K2.

Menaquinone plays an important role in human life support processes, as it potentiates the formation of new bone tissue cells, promotes the absorption of calcium, and participates in blood clotting reactions. Moreover, some protein structures of the body, in particular, elements located in the tissues of the heart and lungs, are synthesized only in the presence of vitamin K2. In addition, the substance acts as an indispensable assistant in the development of osteoporosis in the elderly.

Physical and chemical properties

Vitamin K2 is a yellow crystalline powder, soluble in organic solvents (anhydrous ethanol, chloroform, benzene, ether) and practically insoluble in water. A feature of the nutrient is the ability to redox transformations: under the influence of hydrogen, it easily turns into colorless naphthohydroquinones, which, in the presence of oxygen, are again converted into colored quinones. The adsorption spectra of menaquinones and phylloquinones are similar, however, the former substances absorb ultraviolet radiation less intensively. Maxima of vitamin K2 in hexane lie at 243, 249, 260, 325 nanometers. At the same time, due to the sensitivity of the substance to ultraviolet, these absorption spectra rapidly disappear. To determine vitamin K2 in pure solutions, in 90% of cases, spectral analysis is used, and infrared spectroscopy is used to identify menaquinone homologues.

The antihemorrhagic nutrient belongs to the fat-soluble category of naphthoquinones. Among which, menaquinones are characterized by the longest half-life, due to the greater number of isoprenoid units in the side chain. For example, compounds of the MK-7 type circulate in the blood stream for 72 hours, as a result of which they have time to accumulate in the liver and spread to all organs, including bones and blood vessels (unlike vitamin K1).

The melting point of menaquinone is 53.5 - 54.5 degrees, which causes the compound to be unstable in the external environment.

The structural formula of the substance is 2-methyl-3-difarnesyl-1,4-naphthoquinone.

Natural vitamins K2 and K1 can be modified into each other. Interestingly, in the body of birds and mammals, phylloquinones are converted into menaquinones.

The importance of vitamin K2 in the human body

The metabolic role of the nutrient is due to its participation in the modification of bone tissue proteins and the blood coagulation system. When starting coagulation processes, menaquinone acts as a stimulator of the biosynthesis of enzyme structures necessary for the formation of active forms of thrombin and thromboplastin: prothrombin (factor II), proconvertin (factor VII), plasma thromboplastic component (factor IX), Stuart-Prower factor (factor X). Along with this, vitamin K2 activates osteocalcin (non-collagen bone protein), which is involved in the construction of bone and joint tissues. Thanks to this, the human skeleton acquires strength, density and strength.

Consider why else it is needed in the human body.

Other useful properties of menaquinone:

  • improves the functional condition of the teeth;
  • participates in the mechanisms of vascular cleansing, removing crystallized calcium;
  • regulates redox processes in the body;
  • improves the functioning of the digestive tract;
  • supports the functional activity of the liver and heart;
  • enhances intestinal peristalsis;
  • inhibits the development of malignant neoplasms (according to studies published in the Journal of the American Medical Association);
  • improves the appearance of the dermis;
  • prevents premature skin aging;
  • is involved in intracellular respiration;
  • blocks the synthesis of excess osteoclasts.

Remember, for maximum results, vitamin K2 should be combined with other nutrients (calcium, cholecalciferol, organic vitamin C ) while maintaining a balanced diet and an active lifestyle.


Deficiency and excess

In a healthy body, vitamin K2 is produced by bacteria in the small intestine. Under the influence of bile acids, it turns into lipoprotein, which is delivered to the lymph and then to the bloodstream. Interestingly, 70% of menaquinone accumulates in the liver, although body tissues are able to extract it directly from the blood.

The physiological requirement of the body for vitamin K2 for adults is 100-120 micrograms per day, for children - 30-75 micrograms.

Today, most people, due to intestinal dysbacteriosis that arose on the background of malnutrition or drug therapy, have a deficiency of menaquinone in the body.

Factors provoking the development of K2 deficiency:

  • cholelithiasis;
  • cirrhosis of the liver;
  • hepatitis;
  • neoplasms in the pancreas;
  • prolonged use of antibiotics, sulfonamides and drugs that thin the blood, inhibiting the intestinal microflora;
  • functional disorders of the digestive tract due to stress, unbalanced nutrition, congenital pathologies, chronic diseases of the endocrine ring.

Hypovitaminosis K2 manifests itself in various ways, provoking the development of disease states.

Symptoms of menaquinone deficiency:

  • bleeding and sore gums;
  • fatigue, loss of strength;
  • painful periods in women;
  • bowel disorders;
  • deterioration of the functional state of the skin and hair;
  • bruising from minor injuries or blows;
  • epistaxis;
  • joint pain;
  • prolonged healing of wounds and abrasions;
  • hemorrhages on the retina.

Prolonged lack of vitamin K2 provokes cartilage ossification, development of internal bleeding, salt deposition on the walls of blood vessels, deformation of the musculoskeletal system.

Pregnant women and infants are at risk for K2 hypovitaminosis due to possible hemorrhagic problems during childbirth. For their prevention, expectant mothers are prescribed pharmaceutical products that contain vitamin K2 6 to 8 days before the birth of the baby. The doctor selects the dosage on an individual basis, assessing the risk of developing hemorrhages, the state of health of the woman and the developing fetus. With a lack of menaquinone, children develop loose stools, bloody vomiting, external and internal bleeding.

Hypervitaminosis K2 is quite rare, since the compounds of this group are non-toxic substances. However, long-term intake of large portions of "pharmaceutical menaquinones" (more than 370 micrograms per day) leads to an increase in blood clotting, the development of vascular thrombosis and the provocation of cardiovascular disorders.

Symptoms of an overdose of vitamin K2 in the body:

  • dry skin;
  • nausea;
  • spontaneous miscarriage (in pregnant women);
  • diarrhea.

Remember, vitamin K2 for medicinal purposes should only be taken under medical supervision.

Medical use of menaquinone

In medical practice, nutrient K2 is used primarily as a homeostatic and "bone-strengthening" remedy. In addition, the compound is effectively used in the treatment of disorders associated with anabolic and energy disorders in the body.

Instructions for the use of menaquinone

Consider the cases in which an additional intake of synthetic vitamin K2 is prescribed.

Human use (indication):

  • menaquinone hypo- and avitaminosis;
  • taking hormonal corticosteroid drugs;
  • osteoporosis, osteomalacia (decrease in bone mineralization), osteomyelitis (purulent inflammation of the bone), osteodystrophy of renal origin;
  • fractures of bones and spine;
  • arthritis;
  • diabetes mellitus ;
  • hypo- and hyperthyroidism of the thyroid gland;
  • systemic lupus erythematosus with skin lesions;
  • diseases of the digestive tract;
  • hemorrhagic diathesis, psoriasis;
  • hay fever;
  • bleeding of various origins;
  • pre- and postoperative periods in liver or abdominal surgery;
  • peri- and postmenopausal women;
  • chronic respiratory disease;
  • prevention and treatment of malignant neoplasms of the breast, prostate, ovaries, brain, leukemia;
  • therapy with antibiotics or drugs that inhibit the intestinal microflora;
  • tuberculosis ;
  • complications of anticoagulant therapy;
  • reduced immunity;
  • multiple sclerosis (in complex therapy);
  • chronic kidney disease with excess calcium in the urine.

Given that menaquinone is characterized by a long breakdown period, small doses are required for the correction of functional disorders in the body: for adults - 100 - 150 micrograms per day, for children - 30 - 85 micrograms.

The nutrient is taken 1 time per day during or immediately after a meal with 100 milliliters of pure water.

Contraindications: predisposition to thrombosis, recent stroke or heart attack, heart failure, taking blood thinners.

Sources of menaquinone

Since vitamin K2 plays a key role in the human body: it is involved in the mechanisms of blood clotting, building bone and joint tissues, it is necessary to monitor the level of its intake with food weekly. Consider what foods contain vitamin K2 in its natural form.

) ) ​​
Table No. 1 "Sources of natural menaquinone"
Product name Content of vitamin K2 in 100 grams of the product, micrograms
Soy natto 875
Goose liver (pate) 370
Gouda or Brie cheese 270
Hard cheeses 75
Soft cheeses 55
Egg yolk 20 – 30
Curd 25
Butter 16
Chicken liver 14
Salami sausage 9
Chicken breast 9
Chicken leg 8.5
Ground beef 8
Bacon 5.5
Calf's liver 5
Sauerkraut 4.5
Whole milk (2-4% fat) 1
Flounder, sea bass 0.2
Egg white 0.2

in almost all "green" vegetables (leaf lettuce, parsley, avocado, kiwi, broccoli, spinach, nettle), in vegetable oils (olive and soybean), wheat bran, fish oil, cereals. However, the highest concentration of menaquinones in food, which contains milk and animal protein.

Vitamin K2 preparations

Pharmaceutical form is a valid alternative to a natural source of vitamin K2. Menaquinone-based preparations are used to prevent hemorrhages in newborns, reduce blood loss before surgery, prevent osteoporosis in the elderly, reduce bleeding caused by drugs or poor plasma clotting.

Consider K2 - vitamin preparations:

  1. Vita K2 (Eurocaps Ltd) - a complex drug for the prevention and treatment of atherosclerosis, osteoporosis, hemorrhagic anomalies. One capsule contains nutrient K2 (45 micrograms), vitamin D 3 (5 micrograms), flax seed oil.
  2. Vitamin K2 (Now Foods) - organic menaquinone (MK-7) supplement with alfalfa sprouts. 1 capsule contains a daily dose of vitamin - 100 micrograms. The drug supports the health of the bone and coagulation systems of the body.
  3. Vitamin K2 (Swanson) is a single product derived from fermented natto soybeans. Contains the most stable form of menaquinone - MK - 7 (50 micrograms in 1 capsule). The tool is used to improve the functioning of the heart and liver, increase the absorption of calcium, strengthen the strength of bone and joint tissues.
  4. Vitamin K2 (Source Naturals) is a two-component organic dietary supplement containing vitamin K2 (MK-7) and cholecalciferol. The capsule contains 100 micrograms of MK - 7 and 400 IU of vitamin D 3. The American vitamin complex is an effective assistant in the fight against atherosclerosis, osteoporosis and osteomalacia.
  5. Vitamin K2 (Jarrow Formulas) is a pure menaquinone isolated from fermented soybeans. 1 capsule contains 90 micrograms of the active substance (MK - 7). This form of the compound is 10 times more effective than substances of group K1 obtained from spinach leaves. At the same time, MK - 7 maintains arterial elasticity of blood vessels, regulates bone density, and prevents calcium from sticking to the walls of the capillary bed.
  6. Viva-K2 - Vivasan (Dr. Duenner) - a Swiss preparation based on vitamins K2, D3, linseed and sunflower oils. Regular intake of this remedy prevents leaching of calcium from the bones, destruction of bone tissue, the development of osteoporosis and rickets (in children). In addition, Viva-K2 helps to normalize the function of the thyroid gland, blood clotting, and the contractility of the heart muscle. 1 tablet contains 45 micrograms of vitamin K2 and 5 micrograms of cholecalciferol.
  7. Vitamin K2 (Dr. Mercola) - premium supplement based on menaquinone - 7 (150 micrograms per capsule). K-vitamin monopreparation strengthens bone tissue, regulates metabolism, improves memory, fights against premature skin aging, acts as a powerful antioxidant.

These drugs are included in the catalog of drugs with K-vitamin activity. If, while taking supplements, there is a need for anticoagulants, antibiotics, sulfonamides, or the use of large portions of vitamin E (about 2200 IU per day), a doctor should be consulted, since these compounds inhibit the absorption of menaquinones in the intestine.

Vitamin K2 in osteoporosis

Osteoporosis is a systemic skeletal disease caused by a decrease in bone mineralization, resulting in bone fragility and an increased risk of fractures.

This process is triggered due to a violation of the absorption of the following essential "building materials" for the human body: calcium and osteocalcin. The latter, in turn, is a non-collagen protein that protects bones from damage.

Calcium and osteocalcin metabolism occurs only in the presence of vitamin K2. Recent studies, in particular, experiments sponsored by the National Institutes of Health, indicate that pathological changes in bones begin at the nanostructural level. Biochemists have found that when falling, moving, or any impact on the bone, a pair of combined proteins (osteocalcin and osteopontin) is deformed, causing the appearance of a "hole" with a diameter of 450 - 500 atoms. These holes, called longitudinal stripes, are a protective reaction of the body, due to which the “repayment” of the force of movement occurs without the formation of large gaps. Thus, cracks and fractures occur only under the influence of too strong external influences.

Biochemists believe that an increase in the concentration of "building" proteins in the body will help prevent pathological changes in the structure of bone and dental tissues. However, the assimilation of these proteins is possible only after the introduction of a carboxyl group into the protein compound in the presence of vitamin K2 (in the carboxylation cycle). Therefore, when stimulating the synthesis of osteocalcin, it is advisable to increase the level of consumption of foods rich in menaquinone. This is evidenced by studies by Japanese biochemists (Kawasaki Medical School): scientists have identified the effect of fermented soybeans on bone strength and markers of bone metabolism in healthy women during menopause. The experiment involved seventy-three patients who were divided into four groups, depending on age and the number of births in history. Persons of the first category did not consume beans, women of the second group received a K-containing product once a month, in the diet of the third group soy was present once a week, in the menu of the fourth - three times in seven days.

The duration of the experiment was extended for a year. Throughout the study period, the patients were subjected to regular bone strength monitoring (ultrasound). In addition, 6 months after the start and immediately after the end of the trial, they were assessed for markers of bone metabolism. During the experiment, doctors recorded that in the fourth group of women, the level of bone-specific alkaline phosphatase was higher than in the third, and the degree of carboxylated osteocalcin was significantly lower compared to the first three. Doctors noted that the risk of reducing bone formation in the fourth group is two times less than in the first. Based on the data obtained, the scientists came to the conclusion that for older people, including postmenopausal women, it is advisable to consume foods rich in vitamin K2 three times a week to increase bone mineralization. In addition, for the prevention of osteoporosis, four times a year, take "menaquinone" complexes for 30 days.

Thus, vitamin K2 is one of the most important fat-soluble nutrients necessary for the proper metabolism of calcium and the synthesis of protein structures. Regular intake of natural menaquinone will help minimize the risk of developing bone osteoporosis, cardiovascular pathologies, hemorrhagic abnormalities, including bleeding gums. Along with this, the compounds of the K2 group slow down the aging of the skin, improving its appearance and preventing the appearance of wrinkles. Despite the fact that the vitamin can be produced independently in the small intestine, it is important to consume K2-containing foods three times a week as a preventive measure. The greatest amount of menaquinone is in soybeans, meat and protein foods.

For the full absorption of vitamin K2, it is important to consume foods rich in this nutrient with healthy fats (eg, with 5 milliliters of olive oil).