Most of us remember the vitamins A, B, C, and D. But, there is one less remembered, but by no means less important vitamin – Vitamin K.
This unique vitamin was discovered in the early 1930s. It was recognized initially for its role in coagulation. Its name is derived from the German word “koagulationsvitamin”.
Vitamin K is actually a generic name for a family of fat-soluble vitamins that produce a protein called prothrombin needed for blood clotting and bone metabolism.
The two main forms of the vitamin are:
- Vitamin K1 (Phylloquinone) which is more commonly found in green leafy veggies, and
- Vitamin K2 (Menaquinone), found in small amounts in organ meats and fermented foods.
Vitamin K2 is further divided into subtypes, out of which MK4 and MK7 are more significant. It has only recently started gaining attention with regards to its effects on bone health, heart diseases, cancer, and more. Vit K2 is required to activate osteocalcin, a protein secreted by osteoblasts, which are bone-building cells.
Since Vitamin K1 is more available in our normal diets, its deficiency is almost non-existent, unlike Vitamin K2. This is why K2 supplements were developed to provide a more convenient source of K2 for our daily diet.
Below is our list of the best 6 K2 supplements that are on the market now.
Our Best Picks
1. Best Vegan K2 Supplement – Vitamin D3 + K2 with Organic Coconut Oil
2. Best Gut-Healthy K2 Supplement – LiveWell’s K2+D3 With Natural MenaQ7®
3. Best High-Strength K2 Supplement – NutriZing’s High Strength Vitamin K2 Supplement
4. Best Overall K2 Supplement – InnovixLabs Full Spectrum Vitamin K2
5. Best Budget-friendly K2 Supplement – Jarrow Formulas MK-7
6. Best K2 Supplement with a High Absorption Rate – Doctor’s Best Natural Vitamin K2 MK-7
1. Best Vegan K2 Supplement: Sports Research’s Vitamin D3 + K2 with Organic Coconut Oil
We all know how Vitamin D is essential for bone health and supporting the immune system. It stimulates calcium absorption and reduces calcium excretion.
To add this super vitamin to the K2 supplement only enhances its benefits.
Sports Research D3+K2 supplement uses completely vegan sources for their ingredients, and even their capsules are plant-based. This makes it a great choice for vegans.
About Sports Research’s Vitamin D3+K2 with Organic Coconut Oil
Sports Research is a family-owned company that uses VegaDELIGHT®, a patented D3 extracted from Lichen and MenaQ7®, a patented form of MK7 sourced from chickpeas combined with the goodness of coconut oil. This is then wrapped up in soft veggie gel made of modified tapioca starch.
SR’s D3+K2 supplements are vegan certified and non-GMO project certified, their product ensures to be soy, gluten, and carrageenan-free with no artificial flavors or coloring.
What it Contains:
A serving of 1 soft gel consists of:
- Vitamin K (as Menaquinone 7 K2) – 100mcg
- Vitamin D (as cholecalciferol D3) – 125mcg
It also contains organic virgin coconut oil, rice bran oil, and a tapioca-based gel.
Manufacturers recommend taking one liquid veggie soft gel daily. The murky appearance of the liquid inside can be attributed to the coconut oil.
The Pros:
- Non-GMO
- Vegan certified
- Soy, gluten, and carrageenan-free
- No artificial colors or flavors
Summary: SR’s D3+K2 with coconut oil supplement provides a great vegan option that combines the positive effects of D3 and K2 for your dietary needs.
2. Best Gut-Healthy K2 Supplement – LiveWell’s K2+D3 With Natural MenaQ7®
Cholestasis is a condition that some suffer (especially those with coeliac disease) wherein their body either isn’t producing enough bile or there is some obstruction.
Bile is essential in the absorption of fat-soluble vitamins and minerals such as calcium and magnesium. Adding MCT oil (a medium-density triglyceride) can greatly improve their absorption through the intestines (1), (2).
LiveWell wisely took that into account when they formulated their supplement with MCT oil, boosting its function.
About LiveWell’s K2+D3 with Natural MenaQ7®
LiveWell’s K2+D3 supplement is a US-manufactured product that incorporates natural MenaQ7, which has shown benefits for bone mineral density and blood vessel integrity (3).
The supplement formulation and labeling are all third-party tested to ensure authenticity. They are produced in a GMP-certified facility that uses completely vegan ingredients.
What it Contains:
The serving size of 1 soft gel consists of:
- Vitamin K2 (as MenaQ7®) – 100mcg
- Vitamin D3 (as cholecalciferol) – 125mcg
Each container provides a 60 day supply of the supplement.
The manufacturers recommend taking one soft gel a day with 8oz of water along with a meal.
The Pros:
- Soy, gluten, and dairy-free
- Sugar, and shellfish-free
- No artificial preservatives
- Third-party tested
Summary: LiveWell’s K2+D3 supplement is formulated with MCT oil which boosts absorption for those with disturbed absorption and digestion issues.
3. Best High-Strength K2 Supplement: NutriZing’s High Strength Vitamin K2 Supplement
Natto is a traditional Japanese fermented soybean food that is known to contain Vitamin K2. In fact, it is the richest source of plant-based K2 there is!
This is why we have NutriZing’s HIgh strength vitamin K2 supplement on our list. Their award-winning product is completely natto-based. So it’s jammed packed with top quality, high strength menaquinone-7.
In addition to that, as it is all trans fat isomers, their absorption is also better.
About Nutrizing’s High Strength Vitamin K2 Supplement
Established in 2014, this GMP-certified brand manufactures its product in non-GMO facilities under ISO guidelines. Their K2 supplement contains the more effective MK-7 type of Vitamin K rather than the MK-4. They use premium ingredients while keeping the final product gluten, dairy, nut, and corn-free.
What it Contains:
The serving size of 1 capsule has:
- Vitamin K2 MK7 (as menaquinone) – 600mcg
Other ingredients include microcrystalline cellulose and the capsule which is veggie-based.
The Pros:
- Non-GMO
- GMP certified
- HIgh strength natto-based Vitamin K2
- Gluten, nut, dairy-free
Summary: Nutrizing’s vitamin K2 supplement is a high strength supplement that sources its MK7 ingredient from natto itself, making it rich and highly effective.
4. Best Overall K2 Supplement: InnovixLabs Full Spectrum Vitamin K2
This California based product is our choice for the best overall Vitamin K2 supplement for a couple of reasons. InnovixLabs Full Spectrum vitamin K2 delivers both MK4 and MK7 forms of vitamin K2, thus ensuring the goodness of both in one pill. The MK4 and MK7 are contained in their bioactive ‘trans’ form which is easily recognized and absorbed.
Size-wise, these are tiny and easy to swallow pills. For those who struggle with pills in general, having them tiny helps.
About InnovixLabs Full Spectrum Vitamin K2
InnovixLabs Vitamin K2 supplement is manufactured in a GMP certified facility and they are third-party tested for freshness, purity, and potency. Their product is non-GMO and does not contain any soy, gluten, or dairy.
The raw materials used to make their vitamin K2 are plants. The starting raw materials used are Geranium flower petals and Acacia tree essential oil. The bovine gelatin used for the capsule is Halal certified.
What it Contains:
The serving size of 1 naturally caramel-colored capsule consists of:
- Vitamin K2 MK4 (as menatetrenone) – 500mcg
- Vitamin K2 MK7 (as menaquinone-7) – 100mcg
Other ingredients include virgin olive oil, medium-chain triglyceride oil, and gelatin as its capsule.
They suggest taking one capsule per day for general health. If for heart and arterial health, take two capsules per day. It is best if consumed with a meal.
The Pros:
- Non-GMO
- Soy and gluten-free
- Third-party tested
- Tiny and easy to swallow
Summary: InnovixLabs Full Spectrum vitamin K2 supplements provide both MK4 and MK7 forms of Vitamin K2 in your diet, in an easy to swallow capsule.
5. Best Budget-Friendly K2 Supplement: Jarrow Formulas MK-7
When looking into buying a dietary supplement, we don’t just look for its quality, we keep an eye on its cost. Since these supplements are a daily long term affair, which we must replenish regularly in order to reap its benefits, they mustn’t break the bank!
We chose Jarrow Formulas’ MK7 for not just its quality but also its very affordable pricing. The lower cost helps to ease the burden for those who are already spending a lot on other medications.
About Jarrow Formulas MK7
Jarrow Formulas® MK-7 is naturally made via fermentation by Bacillus subtilis subspecies Natto. They are non-dairy, gluten, and peanut/tree nut-free. They do not use eggs or fish/shellfish in their products either. The supplement uses vitaMK7®, a registered trademark of Gnosis, for Menaquinone-7.
What it Contains:
Serving size of 1 softgel has:
- Vitamin K2 (as Natural MK7) – 90mcg
Along with non-GMO medium-chain triglycerides and olive oil. The softgel consists of bovine gelatin (BSE-free), glycerin, purified water, and organic caramel. One container provides a two month supply of the supplement.
They recommend having one softgel a day with a meal, or otherwise instructed by a health professional.
The Pros:
- Budget-friendly
- Gluten, soy, and dairy-free
- No eggs or fish/shellfish
Summary: Jarrow Formulas MK7 is a good quality supplement that provides MK7 form of vitamin K2 at a very affordable price.
6. The Best K2 Supplement with a High Absorption Rate: Doctor’s Best Natural Vitamin K2 Mk-7 with MenaQ7
Vitamin K2, when compared to K1, gets absorbed much better. Additionally, it is more available in the blood than K1 (4). Both these features have a role to play in how Vit K2 benefits the body. It helps to have a greater absorption rate as that means, better bioavailability. This is exactly what Doctor’s Best Natural Vit K2 offers.
About Doctor’s Best Natural Vitamin K2 supplements
Their products are manufactured in the US using qualified cGMP manufacturers and are third party tested. Doctor’s Best uses quality K2 extracted from fermented chickpeas. They are gluten-free and soy-free. Their veggie-based gels make them completely vegan too.
The small amount of rosemary extract in the product has an added bonus of helping in the bile, which aids in fat digestion (5).
What it Contains:
1 veggie capsule (which is the serving size) includes:
- Vitamin K2 (from MenaQ7®) – 100mcg
Along with ascorbyl palmitate and rosemary extract, all rolled into a vegetarian capsule.
The manufacturers recommend consuming one capsule daily with your meal.
The Pros:
- Non-GMO
- cGMP facility
- Gluten and soy-free
- Vegan
Summary: Doctor’s Best Natural Vitamin K2 supplement uses natural MenaQ7 purified from fermented chickpeas for optimum bioavailability.
Vitamin K2 and Heart Health
One of the factors that can lead to the development of cardiovascular diseases is arterial narrowing because of calcium buildup along its walls (6). This narrowing forces the heart to work harder to pump blood into vessels, which strains the heart muscles and causes artery stiffening as well.
Vitamin K2 has been shown to reduce the risk of vascular damage, and by extension coronary heart disease. The K2 activated osteocalcin protein also activates another protein called Matrix Gla Protein (MGP). This inhibits the deposits of calcium on the vessel walls (7), (8).
A study was done on Menaquinone-7 (MK7) and its effect on arterial stiffness which showed that MK7 supplementation has a beneficial effect on the pulse wave velocity (9).
Most patients on hemodialysis have a functional vitamin K deficiency. A randomized controlled trial was conducted in 2012 on 53 long-term dialysis patients. The results justified the rationale of a daily supplement of K2 to help in improving the bioactivity of VItamin K dependent proteins (10).
A review published in the Journal of Thrombosis and Haemostasis in 2008 suggested that an adequate vitamin K intake is essential to maintain the risk and rate of calcification as low as possible (11).
Summary: Vitamin K2 is essential for the inhibition of calcium deposits on the blood vessel walls and in turn reduces the risk of cardiovascular disease.
Dosage and Instructions
When it comes to the dosage requirements of K2, we can only go by limited data. The recommended dose for K2 isn’t specific.
Studies have shown that an average daily dose of 90-120mcg of Vit K2 can greatly increase the osteocalcin activation (12), (13).
The findings of a randomized controlled trial conducted in 2013 showed that a dose of 180mcg of Vit K2 (in the form of MK7) resulted in a significant reduction of age-related bone mineral content and density (14).
When it comes to the effects of Vitamin K2 on blood vessel health, a study published in 2015 noted an improvement in arterial stiffness when supplementing with 180mcg of MK7 a day (15).
Yet another study done to examine the effects of Vit K2 on the progression of atherosclerosis and calcification of the blood vessels, noted that a daily dose of 90mcg of Vit K2 reduces its progression (16).
Folks living with rheumatoid arthritis(RA) have been shown to benefit from Vit K2 supplementation (17). These patients have an increased risk of osteoporosis as well. In a cross-sectional study, 84 RA patients showed a marked decrease in disease activity when administered 100mcg of MK7 a day for 3 months (18).
Instructions:
Most of the studies done on this subject aren’t very particular about the timing of supplementation, as in what time of day. Although, almost all of the research suggests that a daily, long-term consumption is more likely to bring out the beneficial effects of Vit K2.
Summary: The recommended dosage of Vit K2 supplements is an average of 90-140mcg daily to get the best out of the nutrient.
Risks and Side Effects of K2 Supplementation
Now for a few words on the risks and side effects of integrating K2 into your daily diet. There are a couple of situations where caution must be exercised when consuming Vit K2.
Vit K2 and Soy allergies: The best source of menaquinone-7 (MK7) is from fermented soy (like natto). So for those with soy allergies, it is not advisable to consume supplements sourcing their Vit K2 from soy.
Vit K2 and Anticoagulants: Those individuals who are on blood thinners like warfarin must be cautious about Vit K2 supplementation as both Vit K1 and K2 produce a protein called prothrombin, that promotes blood clotting.
In such conditions, please consult your healthcare provider and decide on a treatment plan.
Vit K2 and Pregnant and/or breastfeeding mothers: Although Vit K supplementation during pregnancy and breastfeeding aren’t discouraged per se, as pregnant mothers require a higher nutrient supply anyway, the dosages vary. It is better to consult the OB/GYN before taking the supplements.
Vit K and Bile obstruction: For conditions where bile secretion is obstructed like obstructive jaundice, it is recommended to take Vit K2 supplements with bile salts (19).
Other side effects may include:
- Decreased appetite
- Muscle stiffness
- Decreased movement or activity
- Irritability
Summary: Those with soy allergies and those who are on anticoagulant therapy need to be cautious and consult a healthcare professional.
Frequently Asked Questions (FAQs)
Can Vit K2 Cause High Blood Pressure?
No. It’s actually quite the opposite! Vit K2 deficiency has been linked to high blood pressure and stiffer arteries (20). Vit K2 activates matrix Gla protein that helps to ensure that calcium is transported to bones.
By reducing the calcification of blood vessel walls which can lead to arterial stiffness, it reduces the strain on the heart to pump more and increase blood pressure.
Several studies only prove to confirm the positive effect Vik K2 has on the cardiovascular health of the body (21), (22).
Do we Need to Take Vitamin K2 with Vitamin D3?
Both Vit D and K2 are fat-soluble vitamins. Both play a central role in calcium metabolism. Vitamin D3 ensures that calcium is absorbed easily from the food while K2 (MK-7) activates the protein osteocalcin, which integrates calcium into bone and prevents calcium from being deposited elsewhere.
Many animal and human studies suggest Vit D3 has a positive effect on the metabolism of Vit K2 and also promotes K-dependant bone proteins (23), (24).
They work synergistically for bone and cardiovascular health.
Yet, there are a few studies that have not observed any such synergistic effect of combining Vit D and K2 together (25).
Aggregating all the evidence regarding a combined vitamin D and K supplementation, the majority of the studies found beneficial effects.
Is MK4 Better Than MK7?
Menaquinone-4 (MK4) and Menaquinone-7 (MK7) are subtypes of Vit K2. MK-7 shows the highest activity in humans than MK4.
A study was done to investigate the bioavailability of MK4 and MK7. It revealed that MK7 was better absorbed and reached a maximum level within 6hrs. In addition to that, MK7 was detected up to 48hrs (26).
These findings concluded that MK7 was a greater contributor to the effects of vitamin K2 in the body.
Can Vit K2 be Given to Children?
Children and adolescent bones grow and develop most intensively. Up to 90 percent of peak bone mass is acquired by age 18 in girls and by age 20 in boys. Vit K2 is required to activate osteocalcin, the protein needed for bone-building cells. A 2014 study clearly showed that the levels of osteocalcin in children are 8-10 times higher than in adults, so VIt K2 is required more (27).
A controlled trial conducted in the Netherlands demonstrated that a modest supplementation of MK7 (a form of Vit K2) helped increase the level of K2 in the blood and the bioactivity of osteocalcin (28).
The Final Note
Vitamin K2 has proven itself to be a very essential nutrient in the smooth functioning of the body, be it the skeletal system, cardiac system, or even its antioxidant effect on cancer-causing tumor cells.
This little known nutrient has a great impact on our body, especially our bones and heart. Although Vit K2 is available in food, the kind of foodstuffs that provide Vit K2 aren’t commonly consumed by the general population, which easily exposes us to a deficiency of the nutrient.
A deficiency we can’t afford.
This is where supplementing our diet with Vitamin K2 makes the most sense. Many agree that consuming Vit K2 supplements may help reduce healthcare spending on conditions like osteoporosis and rheumatoid arthritis and offer substantial benefits in terms of age-related bone loss and cardiac efficiency.
With the booming demand for K2 supplements, the “nutraceutical” market is flooded with all kinds of supplements with a dozen permutations and combinations. In such a scenario, choosing a good quality supplement to suit your particular need can become daunting.
Having the right information regarding the different brands available and their beneficial effects helps to make an informed decision. This is what we have tried to do for you.
As always, we strongly recommend those who are looking into taking these K2 supplements alongside any other medication, must consult with their treating physician and decide on the supplement that suits them.
Ultimately, keep in mind that nutritional supplements aren’t a substitute for medicines and must not be used as such.