What is Vitamin K2?
Vitamin K was first discovered in 1929 by a Danish scientist named Henrik Dam. He initially recognized that the component was not Vitamin A, C, D, or E, but could not determine what exactly the compound was. Further experimentation revealed that Dam discovered a new vitamin with antihemorrhagic properties, and he called it a “Koagulations vitamin” or Vitamin K. It was separately discovered by the Canadian dentist Weston Price, who was studying the relationship between dental health and diet in various human populations. He found that populations that did not consume a predominantly industrial diet had high amounts of an unknown nutrient in their system that protected against tooth decay. This nutrient, which he called Activator X, is now thought to be Vitamin K.
Vitamin K is thought to be a product of microbial action and biosynthesis because it is found mostly in leafy greens as well as fermented foods. There are two forms of Vitamin K: K1 and K2. K1 is found in plants, and it is mostly associated with blood clotting, as it assists the liver in creating blood-clotting proteins. K2 is found in meat and fermented foods, and it is further subdivided into several subtypes with multiple uses and benefits. Vitamin K2 activates proteins that regulate calcium levels in the body. There is a synthetic form of Vitamin K, called Vitamin K3, but it was banned by the Food and Drug Administration because it causes severe liver damage.
Benefits and Uses of Vitamin K2
Blood Clotting
Vitamin K2 is considered to be an anti-coagulant. A study on rabbits revealed that Vitamin K2 does this by reducing the total cholesterol, lipid peroxidation, and factor X activity in plasma. Since it can also decalcify arteries, a higher Vitamin K2 intake can prevent blood clots and reduces pressure on the heart as it pumps blood.
Liver
Due to its role in blood coagulation, Vitamin K may be supplied to people suffering from liver diseases linked to abnormal bleeding. When this occurs, a doctor will often give an oral supplement or injection to treat the issue. In one study on the effects of Vitamin K2 and bone health, the researchers coincidentally discovered that Vitamin K2 may prevent liver cancer. Much more research is needed to confirm this.
Bone Health
Vitamin K2’s role in regulating calcium makes it an important nutrient in bone health by inducing bone mineralization. Because of this, Vitamin K2 supplementation is recommended for bone loss conditions like osteoporosis and osteopenia. Clinical trials support this, with a Japanese study showing that Vitamin K2 reduces the incidence of fractures by consuming 45 mg of Vitamin K2 per day. This high dosage is not available in all countries, but other studies show that smaller doses found in dietary supplements like daily multivitamins are still useful in preventing bone fractures.
Heart Disease
The risk of heart disease increases as calcium builds up in arteries. Numerous animal studies and clinical trials confirm that Vitamin K2 reduces vascular calcification, especially in high risk patients who may lack sufficient Vitamin K, like diabetics and post-menopausal women. One study showed a possible correlation between the amount of Vitamin K2 ingested and a lower risk of heart disease. Another study of over 16,000 women showed that for every 10 mcg of Vitamin K2 ingested, the risk of heart disease was reduced by 9%. These studies are epidemiological studies however, and there is still need for controlled clinical trials that study the effects of Vitamin K2 on heart disease, particularly since it is the most prevalent cause of death.
Inflammation
There are some links between Vitamin K2 and inflammatory diseases, such as inflammatory bowel disease (IBD) In one study, there was a correlation between high levels of Vitamin K and lowered inflammation. However, this research is still preliminary and requires further analysis in randomized clinical trials to reveal if there truly is a causal relationship.
Autoimmune Diseases
Vitamin K2 can be used in combination with Vitamin D to insure proper immune system health. However, the role of Vitamin K2 alone in many autoimmune diseases is not well documented scientifically. One which is well documented, however, is rheumatoid arthritis. Vitamin K2 can be used to treat and prevent rheumatoid arthritis, and many medical doctors suggest that even a simple change in diet can provide enough Vitamin K2 to allow for complete remission.
Cancer
Although the evidence is still in preliminary stages, there are promising studies that show a correlation between Vitamin K2 intake and cancer prevention. Laboratory experiments revealed that Vitamin K2 inhibits growth of hematologic cancers like myeloma and lymphoma. Much more research needs to be completed in this area, but groups are working to discover if long term Vitamin K2 intake would work as a cancer prevention medication. Always check with your oncologist before trying natural cancer treatments.
Brain Function
There are limited reports that suggest Vitamin K2 plays a role in cognitive function. There are at least two Vitamin K dependent proteins in the brain, and although those proteins are not directly related to cognition, those proteins do signal to neurons and to the glia which can influence cognitive ability. There are animal studies that suggest Vitamin K2 can influence behavior, but human studies and clinical trials have not yet been performed. Epidemiological evidence suggests that Vitamin K2 improves memory and may even prevent dementia.
Varicose Veins
It is a persistent myth that Vitamin K can treat varicose veins, but there is no scientific evidence to support this, despite the numerous studies that attempted to find a link between the two. Because Vitamin K is known for improving artery health, many have attempted to treat their varicose veins with Vitamin K supplements or a Vitamin K-rich diet. However, the process that creates varicose veins differs from the typical calcification of arteries and cannot be treated with Vitamin K2. Despite this, many still use these methods as well as Vitamin K-enriched topical creams to treat varicose veins and spider veins.
Weight Loss
Vitamin K2 is anecdotally associated with weight loss. Although Vitamin K itself is not the strict cause of weight loss, a diet rich in Vitamin K is a diet laden in healthy foods like asparagus, turnip greens, broccoli, kale, spinach, cabbage, dark green lettuce, dairy, green tea, and meats. That being said, foods in a Vitamin K-rich diet are ones associated with most healthy diet regimens.
Erectile Dysfunction
Erectile dysfunction is a symptom of several conditions that are treated with Vitamin K2, including low testosterone and atherosclerosis. In a strict sense, Vitamin K2 is not meant to treat erectile dysfunction directly. However, if the underlying condition causing erectile dysfunction is caused by a Vitamin K2 deficiency or could be treated with Vitamin K2, then erectile dysfunction can also improve as a result.
Estrogen
Vitamin K and estrogen do not work well together. Research shows that estrogen treatments can actually interfere with Vitamin K absorption. Conversely, Vitamin K inhibits estrogen activity by lowering the ratio of estradiol to estrone, two different types of estrogen hormones.
Eye Sight
Vitamin K2 is thought to play a role in eye health and vision because of its ability to distribute calcium throughout the body. Since it decreases artery calcification, it is also thought that it insures the health of the delicate vascularization of the eye. There is not much research specifically on Vitamin K and its effects on vision itself, but it is well supported scientifically in its role in artery health.
Skin
Research confirms that topical Vitamin K2 treatments prevent, and in some cases lessen, signs of aging by reducing fine lines and wrinkles. It can do this because of its ability to reduce calcification and increase elasticity of the skin. Further research confirms that the inability to process Vitamin K2 or a deficiency can even lead to premature aging and increased wrinkles. Other vitamins necessary for good skin health (e.g. Vitamin A and D) are dependent on Vitamin K2 to function properly.
Teeth
There are decades of studies supporting Vitamin K2’s role in preventing tooth decay and improving the health of the surrounding periodontal tissue. Deficiencies in Vitamin K2 can lead to bleeding gums, although supplementation does not show improvements for this condition. However, Vitamin K2 can reverse tooth decay by reinforcing teeth with Calcium.
Bruising
Vitamin K2 is less known for its ability to treat bruising and discoloration of the skin, however, there is research that shows topical Vitamin K1 treatments can decrease the time it takes to heal bruises, and it can even be used as a treatment following laser therapies and cosmetic injections.
Kidney Stones
Getting the appropriate amount of Vitamin K2 daily can prevent kidney stones. People with kidney stones often secrete a Vitamin K2-dependent compound in order to decalcify them. Without enough Vitamin K2, the stones cannot decalcify and result in severe pain and bloody urine. Although there is not much scientific literature on this, many medical doctors suggest Vitamin K2 daily as a preventative measure.
Acne
Vitamins A and D are known to prevent acne; however, research shows that many proteins in those vitamins depend on Vitamin K2 in order to work properly. Without Vitamin K2, acne prevention decreases as the other vitamins cannot fully function.
Testosterone
Numerous studies show that Vitamin K2 increases testosterone levels in males. One study showed that Vitamin K2 causes testosterone production directly by the testes and not via the brain, and testosterone levels had increased by nearly 70-90% in rats. Some hypothesize that Vitamin K2 may even play a role in prostate health, but further studies are needed on this. Clinical trials have not confirmed this yet in humans, but many people anecdotally promote taking Vitamin K2 supplements to increase testosterone production.
Gut Bacteria
Certain gut bacteria produce Vitamin K2. Studies in rats reveal the quantities of Vitamin K2, but the reasoning behind why this occurs has only been hypothesized and not yet tested. One idea regarding the benefits of bacteria producing Vitamin K2, is to store excess Vitamin K2 in the event of a deficiency.
Blood Pressure
An epidemiological study showed no correlation between the amount of Vitamin K2 and blood pressure levels. However, it is admitted that the initial study that listed these results was small with limited findings. Another study relays that since calcification causes the heart to work harder to pump blood, blood pressure can increase, therefore, the decalcifying properties of Vitamin K2 may prevent high blood pressure.
Hair Loss
Vitamin K2 has been anecdotally linked to hair loss as well as hair loss prevention, but there are not many studies confirming either case. While some claim that it can promote hair growth, others say that the increase in testosterone caused by Vitamin K2 can lead to hair loss and bald patches. Testosterone and balding are scientifically proven to have a causal relationship, but Vitamin K2’s role in that relationship is less certain.
What K2 to take: MK4 or MK7?
There are several subtypes of Vitamin K2, and two of the more common options are MK4 and MK7. The “M” stands for menaquinone, a compound that is synonymous with Vitamin K2. MK4 is considered a short chain menaquinone, whereas MK7 is a long chain menaquinone. Since MK7 has the longer chain, it is the more active of the two and more available for biological reactions that support healthy circulation. Due to this, an MK7 supplement is preferred over an MK4 supplement. MK4 also has a short biological half-life of sixty minutes, making it a poor dietary supplement.
Vitamin K2 Side Effects, Dangers, Safety, Warnings
Vitamin K2 is virtually non-toxic and safe to consume, but it may interact with other drugs and is not recommended in those situations. Anti-coagulants, or blood thinners, will interact with the similar coagulating properties of Vitamin K2.
Some reports claim there are no dangers to taking Vitamin K2 while pregnant. Other reports suggest avoiding Vitamin K2 supplements during pregnancy, as it can cause the infant to have jaundice. There was one interesting study that reported that women who ingested more Vitamin K2 in the first three months of pregnancy were more likely to have babies that cry less.
Side effects are not common, and some side effects are in fact very rare, but if they occur then medical assistance should be sought out immediately. Many of these symptoms may result from a Vitamin K2 allergy. Less common side effects include: decreased appetite, decreased movement, difficulty breathing, enlarged liver, general body swelling, irritability, muscle stiffness, paleness, and yellow eyes or skin. Rare side effects include: difficulty swallowing, irregular breathing, lightheadedness, fainting, shortness of breath, rash, hives, itching, swelling of eyelids, face, or lips, tightness in chest, and wheezing.
Vitamin K2 Dosage: How much should I take?
Most of the Vitamin K1 humans need is adequately taken through diet, however Vitamin K2 may need supplementation particularly because the modern Westernized diet includes less fermented foods than what was historically eaten. The U.S. Food and Nutritional Board recommends a daily intake of Vitamin K2 for men over the age of 19 – 120 mcg, and a daily intake for women over the age of 19 – 90 mcg. Daily multivitamins typically contain some Vitamin K2 that should be adequate in combination with a healthy diet. However, some health conditions may require higher doses of Vitamin K2, as prescribed by a doctor, like osteoporosis and heart disease.
There are no upper limits on the amount of Vitamin K2 in the United States because there are no known toxic effects of ingesting too much Vitamin K2. However, the U.K.’s Food Standards Agency suggests ingesting no more than 1000 mcg per day for a normal person not on blood thinner medications.
Vitamin K2 Deficiency Signs and Symptoms
A Vitamin K2 deficiency is a factor in many conditions including diabetes, osteoporosis, cancer, inflammatory disease, and cardiovascular diseases. There are several preliminary signs and symptoms that a person may have a Vitamin K2 deficiency that range from mild to severe. Those with a Vitamin K2 deficiency may be more prone to bruising and bleeding, as well as dental cavities. Those diagnosed with osteoporosis or who experience frequent or increased fractures may have these conditions due to a deficiency. Autoimmune diseases, heart disease, and diabetes can occasionally be linked to Vitamin K2 deficiency. People may also experience forgetfulness, and along those lines, Vitamin K2 is linked to dementia.
Certain drugs can also lead to a Vitamin K2 deficiency. Warfarin/Coumadin and other anticoagulants used to treat blood clots work by blocking Vitamin K. Although the target of these drugs is Vitamin K1, it actually blocks both forms of Vitamin K. Antibiotics also lead to deficiencies because they work by killing all gut bacteria (both dangerous and healthy bacteria), and there are many gut bacteria that produce Vitamin K2. Estrogen drugs can also interfere with Vitamin K2 absorption. A low fat diet or fat blocking supplements, like statins, can also prevent the body from absorbing Vitamin K2.
Vitamin K2 Fat-Soluble Absorption
If taking a Vitamin K2 supplement (be sure it is an MK7), consume it with fat. Since it is fat-soluble, the supplement will not be absorbed by the body without combining it with fat as well. Vitamin K will compete with other fat-soluble vitamins, like Vitamin D, so it is recommended to take Vitamin D with breakfast, and Vitamin K2 with dinner. This way, the body can maximize absorption.
Best Vitamin K2 Supplement to Buy
I look for a Vitamin K2 that is made free or allergens and GMOs. Also, one that is obviously made from MK7 for all the reasons stated above.
The reason this is my favorite is because its the most bio-available form of K2, it’s free of soy and most importantly it has clinical trial data to back it. That’s pretty rare for supplements so it’s quite the feather on their cap. The best part? It’s one of the cheaper Vitamin K2 supplements on the market. That is a rare combo, high quality, clinical data and the best price.
References:
https://link.springer.com/chapter/10.1007/978-1-4899-1789-8_19
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4052396/
http://jn.nutrition.org/content/134/11/3100.long
https://www.ncbi.nlm.nih.gov/pubmed/19179058
http://www.who.int/mediacentre/factsheets/fs310/en/
https://www.ncbi.nlm.nih.gov/pubmed/9414028
https://www.ncbi.nlm.nih.gov/pubmed/26321585
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3151653/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5026413/
https://www.ncbi.nlm.nih.gov/pubmed/26923488
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5494092/
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https://www.ncbi.nlm.nih.gov/pubmed/17724449
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5037517/
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https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3760599/
https://www.ncbi.nlm.nih.gov/pubmed/25613567
https://www.ncbi.nlm.nih.gov/pubmed/1492156
https://www.ncbi.nlm.nih.gov/pubmed/26389791
Where does magnesium play its role with K2 and D3? Do these three compliment each other? And should one take a supplement that has both MK-4 and MK-7 in it or just MK-7?
Some people believe that magnesium helps metabolize Vitamin D3. I’m not sure if theres any concrete evidence behind it. I personally would take just MK7 as opposed to MK4 + MK7 as it is more bio-available than MK4.
I read to take K2 WITH Vitamin D to improve Vitamin D absorption.
But, you say take one in morning and one in eve; why do the make them in a supplement together, if they need to be taken separate?
I am trying sooooo hard to get my Vitamin D levels UP!
If you take K2 and Vitamin D together they compete with each other. Its of my belief you should take one at breakfast, and one at dinner, both with fats.
I thought MK4 and MK7 had different functions. isn’t one better for the bones?
In my opinion MK7 is a much better all around dietary supplement for all functions.