Vitamin K2: The Missing Link in Combating Modern Chronic Diseases?
Vitamin K is a fat-soluble vitamin whose main purpose is to regulate calcium and blood clotting.[1] There are two types of vitamin K: K1, which is found in leafy greens and blueberries and is necessary for blood clotting, and K2, which is made by bacteria in the gut and found in animal liver, fermented foods, meat, and dairy, and assists in calcium regulation. K2 is the one we are most interested in.
Vitamin K2 is rare in the Western diet, and most people don’t even know of its importance. Some people think that K2 is the missing link between diet and several chronic diseases. In the early 20th century, Dr. Weston Price, who traveled the world studying the relationship between diet and disease in different populations, noticed that the diets of nonindustrial societies were high in an unidentified nutrient that seemed to protect against tooth decay and chronic diseases. He named this mystery nutrient “Activator X,” but he likely identified vitamin K2.
Vitamin K2’s most important function is to regulate calcium deposition.[2] That is, it promotes the calcification of bones and prevents the calcification of blood vessels. Vitamin K2’s primary mechanism of action is through the vitamin K cycle, a metabolic pathway that uses vitamin K to modify proteins. Vitamin K2 is used to attach a carbon dioxide molecule to glutamate in the protein, which then allows the protein to bind calcium ions.
The role vitamin K2 plays is still not well understood, but research has shown it to be beneficial to heart and bone health and may even help fight cancer:
- Improves bone health – The bone-building proteins matrix GLA and osteocalcin are activated by K2 and use it to bind calcium for transport into the bones, which boosts mineralization and strengthens the bones. Osteoporosis, or the weakening of bone tissue, is common in Western countries. Several studies have found that people taking K2 supplements had better bone mineral density and fewer fractures.[3] K2 supplements are even officially recommended for preventing and treating osteoporosis in Japan. Based on its role in bone metabolism, it’s also reasonable to assume that K2 plays a role in dental health
- Helps prevent heart disease – Calcium buildup in the arteries is a major risk factor for heart disease. K2 binds calcium in the arteries, which helps maintain proper arterial flexibility and prevents arterial plaque buildup. In one long-term study, the people with the highest vitamin K2 intake were 52% less likely to develop artery calcification and had a 57% lower risk of dying from heart disease[4]
- May help fight cancer – K2 suppresses the genes that make cells cancerous and expresses the genes that make cells healthy. Several studies have shown that vitamin K2 reduces the recurrence of liver cancer and increases survival times[5]
- Helps prevent diabetes – K2 helps make insulin and increases your insulin sensitivity[6]
- Helps optimize sex hormones – K2 increases testosterone and fertility in men and decreases androgens in women with PCOS[7]
- Enhances exercise performance – K2 increases the ability to utilize energy during bouts of physical activity[8]
There are multiple forms of vitamin K2, referred to as menaquinones, that have side chains of differing lengths (MK-4 through MK-13). MK-5 through MK-13 are produced by bacterial syntheses, such as in fermented foods, while MK-4 is the only form that is from animal sources. This is interesting because our ancestors would not have had widespread access to fermented foods, but animal foods were widely available. MK-4 and MK-7 are the most popular forms of vitamin K2 supplements, but they are not exactly interchangeable.
There is a widespread belief that because MK-7 has a longer half-life than MK-4, that is, it stays in the bloodstream longer, it is more bioavailable than MK-4. But the evidence may suggest otherwise. MK-4 is shown to be quickly absorbed in the body and is stored in the brain, testes, bones, heart, kidneys, pancreas, and salivary glands.[9] MK-7 is not stored in any organs but appears to go straight to the bones and teeth. Meanwhile, in pregnant women, MK-4 is found in the umbilical cord plasma and breast milk, while MK-7 is only found in the placenta and is absent from the umbilical cord and breast milk.[10] This suggests that MK-4 is the version of vitamin K2 needed for childhood development. MK-7 may therefore remain in the blood longer because it is not as useful to the body as MK-4.
MK-4 regulates gene expression in specific ways that no other form of vitamin K does. Meanwhile, it is transported around the body via HDL, so-called “good cholesterol,” while MK-7 is transported by LDL, so-called “bad cholesterol.” From this evidence, it would appear that MK-4 is nature’s preferred form of vitamin K2.
Vitamin K2 works synergistically with other vitamins, in particular with vitamin D, to form strong bones.[11] Vitamin D raises blood calcium levels by increasing calcium absorption through the gut, and vitamin K2 ensures the calcium is deposited in your bones, not your arteries. Studies show that D & K2 together help maintain strong bones and support cardiovascular health better than taking them separately.[12]
Most diets are fairly rich in vitamin K1 but not K2. People used to get proper amounts of vitamin K2 via fermented foods and organ meats, but those are no longer consistently part of most diets. Widespread deficiency of vitamin K2 is caused by an aversion to eating offal, animals raised on grains and soy, factory farms, high antibiotic use in the food supply, soil depletion, processed food, gut dysfunction, and statin use. While both vitamin K1 and K2 are important, research shows that consuming preformed K2 through our diet is crucial for optimal health in humans.[13] This is a supplement that is often an afterthought to taking vitamin D supplements but may be the missing link between diet and disease.
The optimal daily intake of vitamin K2 MK-7 is 100-200mcg, though higher dosages of MK-4 of up to 45mg have been shown to benefit specific conditions such as osteoporosis. Given that vitamin K2 is not widely studied and there are no studies comparing MK-4 directly to MK-7, it is best to supplement with both forms of vitamin K2. Always take vitamin K and other fat-soluble vitamins like A, D, and E with a fat source for maximum absorption. Vitamin K toxicity is extremely rare, but some people report allergic reactions, anxiety, insomnia, and heart palpitations when taking synthetic K2. Vitamin K supplements can also interfere with anticoagulant medication, so talk to your doctor before taking any supplements.
THRIVE contains 100mcg of K2 MK-7 and 500mcg of K2 MK-4, which are the two most important forms of K2.
Note: This article is for educational purposes only and does not constitute medical advice. Always consult a physician before taking any supplement. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4580041/
[2] https://pubmed.ncbi.nlm.nih.gov/22516724/
[3] https://pubmed.ncbi.nlm.nih.gov/16801507/
[4] https://pubmed.ncbi.nlm.nih.gov/15514282/
[5] https://pubmed.ncbi.nlm.nih.gov/16400650/
[6] https://pubmed.ncbi.nlm.nih.gov/29196151/
[7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3180407/
[8] https://pubmed.ncbi.nlm.nih.gov/28646812/
[9] https://pubmed.ncbi.nlm.nih.gov/17982185/
[10] https://pubmed.ncbi.nlm.nih.gov/3348316/
[11] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613455/