Vitamin K2 (Menaquinone-7)
What is Vitamin K2?
Vitamin K is an essential nutrient for blood coagulation. Vitamin K nutrients are a family of fat-soluble molecules which are an essential nutrient for blood coagulation. First discovered in 1929, vitamin K has also been historically associated with protection against tooth decay, increased bone health and prevention of chronic diseases.
The main function of vitamin K is the activation of various proteins which perform essential functions within the body. There are around 12 proteins within the body that remain inactive until they are stimulated by vitamin K.
There are two main forms of vitamin K:
Vitamin K1 (phylloquinone) – abundant in leafy greens and other plant foods
Vitamin K2 (menaquinone) – small amounts found in animal foods, fermented food and gut bacteria.
Vitamin K2 can be particularly difficult to get entirely through diet. Since we can only derive small amounts of vitamin K2 from some foods, supplements are often recommended to many people.
Vitamin K2 can be further divided into nine other subtypes, the most important of which is menaquinone (MK-7). Vitamin K2, particularly MK-7, has become the preferred supplementary form of the vitamin for supporting bone and vascular health.
MK-7 has become the most extensively studies form of vitamin K2 because of its high bioavailability. MK-7 is also one of the most biologically active and stable forms of vitamin K2 inside of the body, meaning that it’s easier to build up consistent levels of these molecules within the blood.
Vitamin K2 (MK-7) has been studies widely in relation to a wide variety of health conditions. Here’s snapshot of the key benefits of Vitamin K2 supplementation:
Supports bone health. A variety of studies have shown that vitamin K2 can help to strengthen bones and increase bone mineral density. This is especially important for women at risk of osteoporosis. This is because vitamin K2 is needed to activate the protein (osteocalcin) which is required for bones to take in calcium. Without enough vitamin K2, bones can’t absorb enough calcium and become weak. Some research has also shown that MK-7 supplements can reduce the symptoms of rheumatoid arthritis.
Heart health. There’s an association between higher K2 intake and lowered risk of cardiovascular disease. According to several studies, vitamin K2 prevents harmful arterial deposits of calcium which are a major risk factor for heart disease.
Anti-cancer effects. Some studies have suggested that vitamin K2 levels may be linked with a lower incidence of cancer. Higher vitamin K2 has been linked 63% lower rates of prostate cancer. Six separate clinical trials have also shown that vitamin K2 supplementation ay improve overall cancer survival rates and reduce recurrence after treatment.
Brain Benefits and Mode of Action
Vitamin K2 (MK-7) supplementation is helpful for a wide variety of body-wide systems. Vitamin K2 is also the principle form of vitamin K which the brain uses. Neuroscientists have begun to reveal some powerful effects in the brain.
Vitamin K2 might be able to boost our cognitive performance. Supplementing with MK-7 appears to help with our ability to learn and ‘mental sharpness’.
Studies have shown that K2 can help with the production of a substance in the brain called myelin. Myelin is the fatty substance which enwraps the axons that neurons use to communicate with each other. This myelin sheath allows for the quick transfer of electrical signals: the stronger the myelin sheath, the quicker and more powerful these electrical signals become.
Enhancing these myelin sheaths might boost our capacity for mental ‘sharpness’ and help a variety of cognitive processes.
Vitamin supplements have also been suggested to help delay cognitive decline which is associated with aging.
Previous studies have shown that higher levels of K2 are associated with better memory, particularly in older adults. As we age, myelin can become dysregulated, which can play a role in poor memory and cognition. By boosting the production of myelin, vitamin K2 might be able to prevent age-related cognitive decline and diseases such as dementia.
Studies have shown that vitamin K2 helps to transport electrons to the mitochondria. Mitochondria, are the ‘powerhouses’ of cells. These tiny pieces of cellular machinery are responsible for creating energy (in the form of ATP). In some fly models, vitamin K2 has been shown to boost mitochondrial function. This might improve neuronal health and protect cells from oxidative stress. The associated increase in energy (ATP) production may also benefit our focus, concentration and energy levels.
Mode of action: Several brain proteins are dependent on vitamin K2. These proteins remain inactive without the presence of vitamin K2, meaning that a variety of neuronal and glial cell functions can be compromised. Vitamin K2 is also vital for the synthesis of sphingolipids which contribute to the formation of myelin which insulates axons. By supporting the synthesis of sphingolipids, vitamin K2 supports optimal myelin production and helps a variety of cognitive processes.
How to Take
Vitamin K supplements work best when taken with other fat-soluble vitamins and co-factors. In particular, vitamin K works best when taken alongside vitamin D. It’s recommended to combine vitamin K2 with vitamins D and A in order to keep nutrient levels in balance.
Vitamin K2 (MK-7) will perform best in powdered or capsule form.
Recommended dose: 90-360µg
MK-7 is highly bioavailable, and requires much lower doses than other vitamin K subtypes. More research is required to understand the safe upper limit for MK-7 supplementation. Large positive effects can be seen at low doses, so it’s sensible to begin at the lower end of the dosage scale.
Vitamin K2 (MK-7) are generally safe and well-tolerated by most people. MK-7 is suitable for long term supplementation. Vitamin K2 supplements can reduce the effectiveness of Warfarin and other blood thinning medications. Hence, anyone taking these medications should consult their doctor before adding K2 to their supplement regime.
Classification: Cognition, Memory and Strength
We’ve classified vitamin K (MK-7) as a cognition and memory enhancer because of its myelin boosting properties. Vitamin K2 (MK-7) can help sharpen mental performance and increase focus and concentration. You may also feel energy boosting benefits and improvement to creative and abstract thought.
We’ve also classified vitamin K2 (MK-7) as a strength promoter because of its ability to strengthen bones and boost vascular health. You may find your physical performance is improved by this supplement.
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