Vitamin K2 can help strengthen your bones and improve your cardiovascular health.
Given the prevalence of osteoporosis and heart disease, that’s a goal just about everyone should strive for.
Several different molecules belong to the family of compounds known as Vitamin K2, and all of them play a critical role in how your body regulates blood clotting, blood vessel structure, and bone health.
Our research team has analyzed the vitamin K2 supplements on the market to determine which are the most potent and most effective—here are our rankings.
1. Sports Research Natural MK-7 Vitamin K2
Sports Research makes a high-quality vitamin K2 supplement that uses the proprietary chickpea extract MK-7 as its source for the vitamin.
Each capsule contains 100 micrograms of vitamin K2, and the capsules are made of vegetarian-friendly glycerine.
To top it off, the vitamin K2 is dissolved in extra virgin organic olive oil, which helps substantially with absorption. All of these perks make it one of the best K2 supplements out there.
2. Zhou Nutrition K2 + D3
If you want to improve your heart health and bone health at the same time, Zhou Nutrition’s K2 + D3 is an excellent choice.
It combines 90 micrograms of vitamin K2 with 5000 IUs of vitamin D3, a critical vitamin for (you guessed it) heart and bone health that many people are chronically lacking, especially in the winter. With no extraneous ingredients and third-party testing for purity and dosage, you can’t go wrong with Zhou K2 + D3.
3. MaryRuth’s Organics Vitamin K2
MaryRuth’s Organics delivers its vitamin K2 supplement in liquid form, dissolved in organic olive oil.
This means the supplement is extremely pure and extremely well absorbed, because the fat-soluble vitamin K2 is ingested in a dissolved format already.
The liquid format means it’s easy to mix into shakes, smoothies, and drinks. Minimalists will love this supplement too, as its sole ingredients are vitamin K2, organic olive oil, and water.
4. InnovixLabs Full Spectrum Vitamin K2
InnovixLabs walks the line between the standard dosage vitamin K2 supplements and those that offer megadose-range amounts of vitamin K2.
It provides 500 micrograms of vitamin K2 in the MK-4 form as well as an additional 100 micrograms in the MK-7 form, so it might be more biologically active than single-form vitamin K supplements.
These are dissolved in a mix of olive oil and MCT oil, so it’s bound to be absorbed well, too.
5. Life Extension Super K
Life Extension Super K is the go-to supplement for people who want a megadose of all three K vitamins.
While K2 has specific uses in arterial and bone health, vitamins K1 and K3 may play a role in health as well. Unlike other vitamin K2 supplements, Life Extensions Super K doesn’t stick to standard dosages–one capsule contains 2600 micrograms of the K vitamins, of which 1000 is vitamin K2.
Most people would be better suited with a standard dosage, but if you know you want a high dose, Life Extension should be your choice.
6. Jarrow Formulas MK-7
Jarrow Formulas delivers 90 micrograms of vitamin K2 in a gelatin-based softgel. The vitamin is dissolved in a mix of medium chain triglycerides and soybean oil, so absorption is likely to be good.
That aside, it’s a pretty standard vitamin K2 supplement, neither standing out or failing on any other front.
7. Solgar Vitamin K2
Solgar Vitamin K2 is a straightforward, simple vitamin K2 supplement with 100 micrograms of vitamin K2 per capsule. The capsule are vegetarian friendly, and delivers a small amount of calcium as well.
Aside from silica as a binder and filler, the supplement design is fairly clean, though not the best.
8. Now MK-7 K2
Now Foods has a vitamin K2 supplement that uses the popular MK-7 extract from chickpeas as its source of the active ingredient, but unfortunately the quality of the rest of the supplement is subpar.
It has a few fillers that the best vitamin K2 supplements don’t have, and it doesn’t deliver the supplement alongside any synergistic vitamins or in a format that’s rapidly absorbed.
9. Nature Made K2
Nature Made is about as basic as you can get in a vitamin K2 supplement. It delivers 100 micrograms of vitamin K2, but it doesn’t use as clean of a supplement design as many of its competitors.
It uses soybean oil to dissolve the vitamin K2, instead of the healthier but more expensive olive oil or coconut oil used by other supplements, and purists will not like the use of artificial coloring agents either.
10. Doctor’s Best Natural Vitamin K2
While it’s a fairly popular vitamin K2 supplement, Doctor’s Best Natural Vitamin K2 gets outclassed by its competitors on several fronts.
Its dosage is half that of most other vitamin K2 supplements, and its ingredients list is bloated with stabilizers, preservatives, and binders that aren’t necessary. It doesn’t deliver its vitamin K2 in a fat-based solvent, so absorption isn’t expected to be great either.
Vitamin K2 benefits and side effects
Vitamin K2 is essential for blood coagulation and plays a vital role in other aspects of creating good health.
If you’ve never heard of it, you’re not alone; vitamin K2 gets little attention in the Western world despite its importance in optimal physical function.
Originally reported by a German scientific publication in 1929 as a key component in the blood clotting process, Koagulationsvitamin came to be known as vitamin K2. (1)
Weston Price, a legendary dentist of the same era who gathered data around the world focused on links between diet and disease, is believed to have discovered vitamin K2 as well. He didn’t know what it was, referring to it as Activator X, and noting in his journals this mystery nutrient appeared to prevent tooth decay and chronic disease in populations who ate non-industrial diets. (2)
Modern science designates the two types of vitamin K as K1 and K2: vitamin K1 is phylloquinone, and is found in leafy green plant foods (and many green drinks); vitamin K2 is menaquinone, occurring in fermented foods and animal products. (3)
Just like all the components of an engine are necessary in order to start the vehicle and drive off, everything in the body is designed to interact and perform various segments of the required processes for running the physical engine.
Vitamin K modifies proteins to facilitate the binding of calcium, an essential mineral for strong bones and good teeth, as well as other bodily functions. (4)
K1 is utilized by the liver in activating the calcium-binding properties of protein that clot blood; K2 activates the proteins in charge of regulating the distribution of calcium throughout the body. (5)
Researchers believe vitamin K2 prevents the build-up of calcium in arteries (6), which is a major risk factor in developing heart disease.
A European study spanning 7 to 10 years found participants who ingested the highest levels of vitamin K2 developed calcification of the arteries at a 52% lower rate than those who got the least, and were 57% less likely to die of heart disease. (7)
When data from a large study of more than 16,000 women was analyzed, the results showed subjects reduced the risk of developing heart disease by 9% for every 10 micrograms of vitamin K2 taken. (8)
In these observational studies, intake of vitamin K1 had no effect on outcomes.
Since cardiovascular disease is the leading cause of death worldwide today (9), clinical trials to determine the role vitamin K2 can play in prevention are vital.
When important micronutrients are missing from the diet, any number of bodily processes can go awry.
1. Bone Health and Reducing the Risk of Osteoporosis
Elderly western women are particularly vulnerable to this disease in which bones become more porous and fracture easily.
When menopausal women took K2 supplements over a three-year period, they experienced reduced rates of declining bone mineral density in comparison to women who took no supplements. (12)
2. After conducting 13 separate trials, Japanese medical authorities recommend high doses of vitamin K2 supplements to prevent and treat osteoporosis. (13)
Only one of these lengthy trials failed to show significant improvement in bone density; more than half the studies confirmed that the occurrence of bone fractures in subjects taking K2 decreased by impressive rates: between 60% and 81% for hip, spinal and non-spinal fractures. (14)
3. Improved Dental Health
Dr. Weston Price believed vitamin K2 was vital for preventing cavities and promoting good oral health, but his theory has not been tested on humans.
Animal studies exploring the role of K2 in bone health indicate a potential link between strong bones and good teeth.
Osteocalcin, the protein important for bone metabolism, also regulates proteins vital for dental health. (17) The growth of new dentin underneath tooth enamel appears to be stimulated by osteocalcin. (18)
Researchers believe vitamin K2 may work in concert with vitamins A and D in keeping teeth strong and free of cavities. (19)
4. Cancer Prevention
While modern science continues to come up with more ways to treat cancer, the incidence of cancer is on the rise. More than 8 million people died of the disease in 2012, and 14 million new cases were diagnosed the same year. (20)
Vitamin K2 has been studied in relation to several types of cancer, including liver cancer. One trial indicated that the recurrence of liver cancer can be reduced by taking vitamin K2 supplements, and another showed lengthier survival periods for patients taking K2. (21, 22)
A large study of 11,000 men concluded a high intake of K2 lowered the risk of advanced prostate cancer by 63%. (23) Vitamin K1 had no effect in the trial.
5. Sources of Vitamin K2
Vitamin K1 is present in a typical diet at approximately ten times the amount of vitamin K2; since the body can convert K1 to K2, this is helpful. But it’s an inefficient process, and eating foods rich in K2 is a good way to make certain you get enough.
Intestinal bacteria are also capable of producing vitamin K2, but evidence suggests this can be negatively impacted by wide-spectrum antibiotics used to treat common illnesses. (24, 25) If you’ve ever taken antibiotics, your ability to manufacture vitamin K2 internally may be compromised.
Unfortunately, foods rich in vitamin K2 aren’t on the top of everyone’s grocery list. Animal foods are good sources of a vitamin K2 subtype called MK-4, and fermented foods help you get subtypes MK-5 through MK-14. (26)
Include these for the first subtype: Dairy products, high-fat and only from grass-fed cows, including cheese and butter, liver and other organ meats and egg yolks.
Fermented foods aren’t eaten as often in modern times, but these are excellent sources of other vitamin K2 subtypes: Miso and natto, fermented soy products and sauerkraut.
Vitamin K2 is fat-soluble, which means the body can access the nutrient only when combined with fat; lean meats have limited amounts of vitamin K2.
Supplements are widely available at reasonable cost, and may be more effective when taken with vitamin D. While the RDA for K2 is 1500 micrograms, dosages up to 45 milligrams (45,000 micrograms) have been safely used in test protocols.
Summary: If you have any doubts that you’re getting enough vitamin K2, adding rich food sources to your diet or taking a supplement could save your life.