Compared to other vitamins, Vitamin K is relatively unheard of. Vitamin K isn’t always readily recognizable even as a dietary supplement. The “K” in vitamin K originally stood for “koagulation” which is the Danish word for coagulation. In line with this, vitamin K plays a key role in coagulation, or blood clotting, which then prevents excessive bleeding from occurring. It also plays a role in bone metabolism and bone remodeling, where mature bone tissue grows new bone tissue.
It is also a fat-soluble vitamin, just like vitamins A, D, and E. This means that the body absorbs the vitamin from the fat you consume. When it’s not in use, the body stores vitamin K in the body’s liver and fat tissues.
Vitamin K comprises a group of vitamins, with the most important ones being K1 and K2. You can get your vitamin K1 from leafy vegetables, olive oil, and soybean oil. Meanwhile, you can also source vitamin K2 from meat, cheese, and eggs. Gut bacteria also produce vitamin K2, whether it’s natural or synthetic. Highly processed foods don’t contain Vitamin K1 and K2.
Both vitamin K variants have the same coagulation factors. Recently, some researchers have speculated that Vitamin K2 could treat osteoporosis and steroid-induced bone loss, but no studies have confirmed this yet. K2 also has a special role in monitoring that calcium goes to the right places, for example; your bones, and making sure it doesn’t build up in places where it shouldn’t, like your kidneys and blood vessels. Vitamin K2 is also essential in the formation of MGP, a protein that blood vessels produce that stops calcium from building up and blocking your blood vessels.
Men who consume high amounts of vitamin K2 also appear to have a lower risk of having advanced prostate cancer.
Vitamin K2 and osteoporosis

As previously mentioned, it’s being looked into whether vitamin K2 is a viable treatment for osteoporosis. K2 assists the body in moving calcium out of your blood and into your bones. This is where bone remodeling comes in. The bone is a living substance that is constantly in a cycle of being destroyed and created. As we grow older, more bones may regenerate less. This ends up increasing the risk of fractures. Now, this is where vitamin K2 comes in. There have been studies that suggest that vitamin K2 affects bone density.
We should also note that 1 in 5 men over the age of 50 will experience an osteoporotic fracture. And that men makeup 20-25% of all hip fractures have an estimated lifetime risk of 30% for experiencing an osteoporotic fracture, especially once they’re over 50, which is like the risk of developing prostate cancer .13 controlled studies focused on how taking vitamin K2 supplements (15 to 45 mg of MK-4, daily) affects bone density and how fracture rates. The studies found that vitamin K2 reduced the risk of spinal fractures by 60%, hip fractures by 77%, and other non-spinal fractures by a whopping 81%.
The NIH declared that the evidence found in vitamin K2 and its aid in preventing osteoporosis remains unclear. Therefore, more studies are needed.
Vitamin K2 in the fight against cancer and cardiovascular disease
Vitamin K2’s role in monitoring calcium isn’t just for the bones, but also your heart. It’s been found that vitamin K2 might reduce the risk of cardiovascular disease because of its role in reducing calcium buildup in the arteries found around the heart.
Vitamin K2 plays a vital role not just in fighting cardiovascular disease, but also in fighting cancer. A study of nearly 25,000 people found that incorporating and consuming dietary vitamin K2 correlated with a lower risk of lung and prostate cancer in men. Another 2008 study of 11,000 men found that those with the highest intake of vitamin K2 had a 63% lower risk of developing advanced prostate cancer.
Getting enough vitamin K2

Food is the best way to increase your intake of vitamin K2. Foods such as; dark chicken meat, liver, egg yolks, cheese, butter, and other dairy products, and natto, which is a traditional Japanese dish made of stringy fermented soybeans.
Of course, you can also find vitamin K2 through vitamin supplements. It’s usually found in multivitamin blends, Vitamin K supplements, and you can even find formulations that are made solely of vitamin K2.
The recommended dose for men, according to the US National Institutes of Health, is a daily intake of 120 mcg of Vitamin K. Therefore, it’s not recommended to take vitamin K in high doses. Researchers have not yet set a maximum safe dose.
K2 and medication
As long as you take vitamin K at recommended doses, it is rare to see any side effects. But many drugs could interfere with the effects of vitamin K. Blood thinners, antibiotics, aspirin, antacids, and medication for cancer, seizures, and high cholesterol are some drugs that could affect vitamin K.
Taking too much vitamin K can also negatively interact with a medication called coumadin. Coumadin is an anticoagulant also known as warfarin. Too much vitamin K can decrease the effectiveness of coumadin and instead can increase the risk of heart attacks and strokes due to blood clots.
Taking too much vitamin K could also lead to vitamin K toxicity. Vitamin K toxicity can rupture red blood cells, leading to anemia.
Be sure to talk to your healthcare professional about the compatibility of your medication before you take vitamin K2 supplements and be sure to only take the recommended dosage. Once again, do not take vitamin K supplements unless they advise you to do so. Anyone using coumadin may need to watch their diet and closely control the amount of vitamin K that they intake.