ビタミンKの機能

ビタミンB12

ビタミンK is a collective name for a series of fat-soluble compounds. They have a common 2-methyl-1,4-naphthoquinone ring, but based on the difference in the side chain at position 3, three main types of vitamin K are defined: Vitamin K or chlorophyllomenadione, vitamin K2 or menadione and vitamin K or menadione.

 In the physiological mechanism of the human body, vitamin K is a necessary molecule for the synthesis of the gamma-carboxyglutamate protein family, and these processes are also called vitamin cycles.

 In addition to being related to the four coagulation factors in the human body, this group of Gla produced by vitamin K also plays a key role in maintaining bone strength, inhibiting vascular wall calcification, maintaining endothelial integrity, participating in tissue renewal, regulating cell growth, etc., and is important. Sex is no less important than other nutrients, so it is also called the forgotten vitamin.

 Vitamin K Reduce vascular calcification

 Vascular calcification, the deposition of minerals as calcium-phosphorus complexes in blood vessels, is an independent predictor of cardiovascular disease and mortality. Studies have shown that calcification is associated with clinically significant coronary artery disease, acute cardiovascular and cerebrovascular events, arterial stiffness and hypertension, and aortic valve disease.

 Although vascular calcification is considered part of the normal aging process, certain pathological processes, such as diabetes, hypertension, chronic kidney disease, and rare genetic disorders, may also lead to vascular calcification.

 A meta-analysis of the literature (including 14 randomized controlled trials with 1,533 participants) showed that vitamin K supplementation (mainly K2 (MK7)) can help improve coronary artery calcium scores and reduce dephosphorylation and decarboxylation matrix Gla protein.

Vitamin K supplementation may be helpful in reducing vascular calcification (especially coronary arteries), but due to the small sample size, more research is needed to further verify it.

 ビタミンK Maintain bone health

 Osteoporosis is an age-related disease characterized by a decrease in bone mass, leading to brittle bones and an increased risk of fractures.

The causes of osteoporosis may be related to endocrine abnormalities, abnormal secretion of parathyroid hormone and calcitonin, insufficient intake of vitamin D and calcium, postmenopausal hormonal status, pregnancy, nutritional disorders, drug use, etc.

 A literature meta-analysis (including 17 prospective randomized controlled studies) pointed out that vitamin K supplementation can help increase lumbar spine BMD, but has no significant effect on femoral neck BMD.

 Another literature meta-analysis (including 19 randomized controlled trials with 6759 participants) pointed out that for postmenopausal women with osteoporosis, additional vitamin K2 supplementation can help maintain and improve spinal bone density, and Can reduce the incidence of fractures.

 A recent meta-analysis of the literature (including 5 studies with a total of 1114 fracture cases and 80982 participants) pointed out that higher dietary vitamin K intake can modestly reduce the risk of fractures.

Appropriate intake of vitamin K has positive effects on bone health and can reduce the incidence of fractures

 Vitamin K Good for diabetes

 Diabetes 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 lifestyle, the global prevalence of diabetes has doubled in 30 years, reaching 8.5% of the total population (approximately 400 million people)

Common complications of type 2 diabetes include: cardiovascular disease, kidney failure, vision loss, nerve damage, etc.

 A meta-analysis of the literature (including 8 randomized controlled trials with 1,077 participants) pointed out that vitamin K supplementation (either K1 or K2) does not affect insulin sensitivity (in terms of insulin resistance, fasting blood glucose, fasting plasma Insulin, C-reactive protein, adiponectin, leptin, and interleukin-6 levels were measured).

 Another literature meta-analysis (meta-analysis, including 5 clinical studies with 533 participants) pointed out that for people without diabetes, vitamin K supplementation has no significant impact on blood sugar control (measurement indicators include fasting blood glucose, 2-hour oral glucose Tolerance test, fasting insulin, insulin resistance).

For healthy people, additional vitamin K supplementation does not bring significant improvements in blood sugar control. More research is needed to confirm the impact on pre-diabetes and people with existing diseases.

Vitamin K Improve coagulation function (for patients taking anticoagulants)

Warfarin is an anticoagulant (also known as a vitamin K antagonist) commonly used for thromboembolism prevention, especially in patients with atrial fibrillation, a history of venous thromboembolism, and artificial valve replacement.

 However, long-term oral anticoagulation with vitamin K antagonists may carry a risk of bleeding or thromboembolic complications.

 Therefore, clinically, coagulation function is regularly tested at an international standardized ratio, and drug dosage adjustments are subsequently made.

The 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, major bleeding and reduce mortality.

 A systematic literature review and meta-analysis (including 4 studies with a total of 678 participants) pointed out that in patients on chronic anticoagulant therapy, there is insufficient evidence to support the need for routine vitamin K supplementation to achieve INR stabilization.

However, for patients with unstable INR without reasonable attribution, vitamin K supplementation may be a viable option to improve INR.

 ビタミンK Good for arteriosclerosis

 Arteriosclerosis is characterized by intima-media thickening, accompanied by increased central arterial lumen, endothelial dysfunction, vascular smooth muscle cell proliferation, increased collagen, and elastin degradation.

Carotid-femoral artery pulse wave velocity is the current 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, increased vascular calcification index: matrix gla protein is also related to aortic stiffness.

 A double-blind, placebo-controlled trial (3 years, 244 healthy postmenopausal women) pointed out that long-term use of MK-7 supplements (vitamin K2) can help improve arteriosclerosis, especially those with higher degrees of arteriosclerosis. object.

In healthy postmenopausal women, taking MK-7 (vitamin K2) may improve aortic stiffness

 Vitamin K Beneficial for chronic kidney disease

 Chronic kidney disease is defined as renal impairment manifested by abnormal albumin excretion or renal insufficiency, with measured or estimated glomerular filtration rate (GFR) as the diagnostic criterion, and persisting for more than three months.

Chronic kidney disease progression is associated with many serious complications, including cardiovascular disease, hyperlipidemia, anemia, and metabolic bone disease

End-stage renal disease and the subsequent need for dialysis or transplantation often account for large total medical costs and impose a heavy burden on patients

 An observational study (13.3 years of follow-up, 3401 participants) found that adequate vitamin K intake was associated with lower all-cause and cardiovascular disease mortality in patients with chronic kidney disease.

 Adequate dietary vitamin K intake may have a positive effect on chronic kidney disease, but further randomized controlled trials are needed to confirm this.