Vitamin K is used to treat and prevent low levels of certain substances (blood clotting factors) that your body naturally produces. These substances help your blood to thicken and stop bleeding normally (e.g., after an accidental cut or injury). Low levels of blood clotting factors increase the risk for unusual bleeding. Low levels may be caused by certain medications (e.g., warfarin) or medical conditions (e.g., obstructive jaundice). Vitamin K helps to treat and prevent unusual bleeding by increasing the body’s production of blood clotting factors.
Vitamin K (vitamin K, also known as vitamin K) is a less-discussed fat-soluble vitamin (there are other vitamin A, vitamin E, and vitamin D). It was first discovered in the 1939s, and the name came from the Danish word koagulation. It means blood clotting, which is a key nutrient for maintaining blood clotting function
In empirical medicine, what effect does vitamin K have? Are there any side effects? See the text analysis for details
What is Vitamin K?
Vitamin K is a class of compounds with similar structures. In the physiological mechanism of the human body, vitamin K is a molecule necessary for the synthesis of gamma carboxyglutamate/Gla-protein, and these processes are also called vitamins. K cycle.
This group of Gla-protein produced by vitamin K is not only related to the four coagulation factors in the human body, but also plays a key role in maintaining bone strength, inhibiting vascular wall calcification, maintaining endothelial integrity, participating in tissue renewal, and regulating cell growth. The importance is no less than other nutrients, so it is also called the forgotten vitamin
What are the types and food sources of vitamin K?
There are two forms of vitamin K in our diet: vitamin K1 and K2
Vitamin K1 (phylloquinone) is mainly found in green leafy vegetables or algae foods
Vitamin K2 (menaquinones) is the most biologically active form. It has a longer half-life than vitamin K1. It is mainly found in foods of animal origin, such as liver or fermented foods, such as yogurt and natto. Bacteria are directly produced, and according to the number of isoprene units, it can be subdivided into MK-1 to MK-10, and MK-7 and MK-4 are the most common
MK-7 is usually derived from natto, a popular Japanese food made from fermented soybeans. Compared with vitamin K1, long-term intake of MK-7 in the blood is not only more stable, but also higher in concentration (up to 7 to 8 times), and the distribution in various tissues is significantly better.
MK-4 is found in animal tissues, or in a small amount in meat and egg yolks.
What are the empirical effects (benefits) of vitamin K?
Maintain bone health
Osteoporosis is an age-related disease characterized by decreased bone mass, leading to weak bones and increased risk of fractures.
The cause of osteoporosis may be related to endocrine, abnormal secretion of parathyroid hormone and calcitonin, insufficient intake of vitamin D and calcium, postmenopausal hormonal status, pregnancy, nutritional disorders, drug use, etc.
＊Conclusion: Appropriate intake of vitamin K has a positive effect on bone health and can reduce the incidence of fractures
Good for diabetes?
Diabetes mellitus is a group of metabolic diseases characterized by chronic hyperglycemia due to defects in insulin secretion, insulin action, or both.
Due to refined diets and changes in lifestyles, the global prevalence of diabetes has doubled in 30 years, reaching 8.5% of the total population (about 400 million people)
Common complications of type 2 diabetes include: cardiovascular disease, renal failure, vision loss, nerve damage, etc.
＊Conclusion: For healthy people, additional vitamin K supplementation failed to bring significant improvement in blood sugar control. More studies are needed to confirm the effect on pre-diabetes and those with pre-diabetes
Improve coagulation function (for patients using anticoagulants)
Warfarin is an anticoagulant (also known as vitamin K antagonist), usually used for thromboembolism prevention, especially for patients with atrial fibrillation, a history of venous thromboembolism, and prosthetic valve replacement
However, long-term use of vitamin K antagonists for oral anticoagulation may have the risk of bleeding or thromboembolic complications.
Therefore, clinically, the coagulation function is regularly tested with the international normalized ratio (INR), and then the drug dose is adjusted.
INR is based on the ratio of the patient’s thrombin time to the normal average thrombin time. When it is between 2 and 3, it is most beneficial to prevent stroke, hemorrhage and reduce mortality
Good for arteriosclerosis
Arterial stiffness is characterized by thickening of the vascular intima-media layer, accompanied by increased central artery lumen, endothelial dysfunction, vascular smooth muscle cell proliferation, increased collagen, and degradation of elastin.
Carotid-femoral pulse wave velocity (CFPWV) is currently the reference standard for measuring aortic sclerosis in the medical community. Abnormal values are related to cardiovascular diseases, including coronary heart disease, stroke and cardiovascular disease mortality.
In addition, the index of vascular calcification: the increase of matrix gla protein (dp-ucMGP) is also related to aortic stiffness. Note 8
＊Conclusion: For healthy post-menopausal women, taking MK-7 (vitamin K2) may improve aortic stiffness
Good for chronic kidney disease
Chronic kidney disease (Chronic kidney disease) is defined as impaired renal function and manifests as abnormal albumin excretion or renal insufficiency. The measured or estimated glomerular filtration rate (GFR) is used as the diagnostic criteria and lasts for more than three months
The progression of chronic kidney disease is associated with many serious complications, including cardiovascular disease, hyperlipidemia, anemia, and metabolic bone disease
End-stage renal disease and subsequent dialysis or transplantation often occupy huge total medical expenses and cause a heavy burden on patients
＊Conclusion: Adequate dietary vitamin K intake may be positively helpful for chronic kidney disease, but randomized controlled trials still need to be further verified
Are there any side effects from vitamin K supplementation?
For most healthy adults, vitamin K1 and vitamin K2 generally rarely have side effects when used in appropriate doses, but it is best to consult a local pharmacist or physician before using any health products to ensure safety
Vitamin K3 (menadione) is extremely rare in the market. It is a synthetic form and is generally not recommended because it inhibits the action of antioxidants (glutathione) and causes oxidative damage. In addition, intravenous injection has experienced liver toxicity, jaundice and hemolytic anemia
Safety precautions (7 point use taboo)
- Pregnant women, breastfeeding mothers, and those with poor liver and kidney function should confirm with their doctor before use (the relevant risks are unknown)
- Rare metabolic disease: do not use for patients with fava bean disease (Glucose-6-Phosphate Dehydrogenase deficiency/G6PD)
- Vitamin K1 may have the effect of lowering blood sugar, diabetic patients or those taking hypoglycemic drugs, please pay special attention
- Do not use together with anticoagulants, such as Warfarin (due to the effect of vitamin K to help blood clotting, it may offset the effects of drugs)
- Taking related drugs that interfere with fat absorption, such as: antiepileptic drugs (Dilantin), antibiotics, cholesterol-lowering drugs (Cholestyramine/cholic acid binding resin), weight loss drugs (Orlistat/Roche fresh), will affect the absorption of fat-soluble vitamins, including vitamins K
- Large doses of vitamin A seem to interfere with the absorption of vitamin K, while large doses of vitamin E may inhibit vitamin K-dependent carboxylase activity and interfere with the coagulation mechanism
- Long-term use of broad-effective antibiotics, such as cephalosporins and salicylates, may interfere with the synthesis of vitamin K in the intestines
Possible symptoms of vitamin K deficiency?
Vitamin K deficiency is not common in healthy adults. The reasons include the following: it is widely found in food, vitamin K cycle can preserve vitamin K, bacteria in the large intestine can synthesize menaquinones (vitamin K2)
Vitamin K deficiency symptoms include easy bruising and bleeding, which may manifest as nosebleeds, bleeding gums, small blood clots under the nails, hematuria, bloody stools, or excessive menstrual bleeding.
What are the groups that are prone to vitamin K deficiency?
Due to the poor efficiency of vitamin K passing through the placenta and the relatively low content of vitamin K in breast milk, this increases the risk of neonatal deficiency of this nutrient
In the first few weeks of life, a lack of vitamin K can lead to vitamin K deficiency bleeding (VKDB), also known as “a typical neonatal bleeding disorder”
This type of bleeding often occurs in the umbilical cord, gastrointestinal tract, skin, nose or other parts, especially in advanced VKDB (occurring in the age of 2-12 weeks), and can also be manifested as sudden intracranial hemorrhage, with extremely high mortality.
To prevent VKDB, the American Academy of Pediatrics recommends a single intramuscular dose of 0.5 to 1 mg of vitamin K1 at birth
Patients with malabsorption disorder:
People with malabsorption syndrome and other gastrointestinal diseases (due to fat malabsorption), such as cystic fibrosis, celiac disease, ulcerative colitis and short bowel syndrome, may not be able to absorb vitamin K smoothly
Subjects who take vitamin K antagonists (anticoagulants) for a long time
Long-term dialysis patients