Product Reviews
Vitamin K Supplements Review (Including Calcium, Vitamin D, Magnesium & Boron)

Reviewed and edited by Tod Cooperman, M.D. Tod Cooperman, M.D.
Initial Posting: 11/23/19  Last Update: 4/28/20

Find the Best Vitamin K Supplement

Tests and Reviews of Popular Vitamin K Supplements & CL's Top Picks

Vitamin K Supplements Reviewed By
Alphabetical list of vitamin K supplements compared in this review
Country Life Vegan K2 Innovix Labs Vitamin K2 Relentless Improvement K2 Menatetrenone
Dr. Mercola Vitamin K2 Jarrow Formulas Bone-Up Thorne Basic Bone Nutrients
GNC Calcimate Complete Life Extension Vitamin D & K With Sea-Iodine Zhou K2 + D3
Healthy Origins Natural Vitamin K2 As MK-7 New Chapter Bone Strength Take Care  
Country Life Vegan K2 Dr. Mercola Vitamin K2 GNC Calcimate Complete Healthy Origins Natural Vitamin K2 As MK-7 Innovix Labs Vitamin K2 Jarrow Formulas Bone-Up Life Extension Vitamin D & K With Sea-Iodine New Chapter Bone Strength Take Care Relentless Improvement K2 Menatetrenone Thorne Basic Bone Nutrients Zhou K2 + D3
Make sure your taking the best vitamin K supplement and it's right for you!
Isn't your health worth it?

If you already are a member, SIGN IN now.
  • What is it? Vitamin K helps with proper blood clotting as well as with calcium utilization in bones and the cardiovascular system (See What It Does).
  • Do you need to take it as a supplement? Most people are not deficient in vitamin K and symptomatic deficiency is rare, so unless you have a malabsorption condition or are severely malnourished, you likely get sufficient vitamin K from your diet (e.g., from green leafy vegetables, dairy, and fermented foods -- see Vitamin K from food). Vitamin K supplements have been clinically tested to increase bone density and reduce fractures, as well as to improve cardiovascular function, but results have been mixed, so it is not clear that supplementation will help (see What It Does).
  • Which form? There are several forms of vitamin K. All are active, but one, the MK-7 form of vitamin K2, can increase blood levels of vitamin K up to 8 times as much as other forms. It's generally more expensive than the others, but it likely that you can take less of it (see What It Is and What to Consider When Buying).
  • How much to take? For adults, adequate daily intake of vitamin K is 90 mcg for women and 120 mcg for men. It is difficult to know what dose may be useful in bone health (or if any dose is truly beneficial). However, studies involving supplements containing K1 or the MK-4 form of K2 tend to use very high doses (e.g., 500 mcg to 45,000 mcg), while studies with the MK-7 form of K2 have used more moderate dosing, e.g., 180 mcg. (See What to Consider When Using).
  • How to take it: Vitamin K is fat soluble, so you'll absorb more of it when you take it with a meal that has fats or oils. Other fat-soluble vitamins, like vitamin D, can compete with its absorption, so take them at least 3 hours apart. (See What to Consider When Using).
  • Best choice? Products vary in quality and cost (See What CL Found). Among Approved products, identified several which represented its Top Picks.
  • Cautions: Vitamin K is fairly safe. However it can interact with certain medications. If you have an allergy to soy, be aware that most MK-7 forms of vitamin K are derived from soy, (See Concerns and Cautions). One branded form of MK-7 (MenaQ7) is derived from chickpeas and claims to be soy-free (See What It Does), although a product containing this form did not pass testing (See What CL Found).
You must be a member to get the full test results along with recommendations and quality ratings. You will get results for 8 vitamin K supplements selected by and 3 others that passed testing in its voluntary Quality Certification Program.

In this comprehensive review, you'll discover:
    • Which vitamin K supplements failed our tests and which ones passed
    •'s Top Picks among vitamin K supplements
    • How to choose a vitamin K supplement that best suits your needs
    • The difference in potency among the popular forms of vitamin K: vitamin K1 and two forms of vitamin K2  -- menaquinone-4 (MK-4) and menaquinone-7 (MK-7)
    • The dose of vitamin K used for specific applications and how to best take it for maximum absorption
    • How to get vitamin K from foods
    • Potential drug interactions and side effects of vitamin K, including interactions with certain anticoagulants and soy allergy  

If you already are a member, SIGN IN now.

Learn More About Vitamin K Answers -- for Vitamin K Supplements Review (Including Calcium, Vitamin D, Magnesium & Boron)
What is the difference between forms of vitamin K2? Get the answer >>

Do any supplements help prevent or treat osteoporosis? Get the answer >>

I'm considering taking vitamin K for my bones, but I take blood thinner (anti-coagulant) medication. Is there a problem taking both? Get the answer >>

Which supplements reduce the risk of stroke? Which increase the risk of stroke? Get the answer >>

Have you tested vitamin K supplements with MenaQ7? Is this a good source of vitamin K if I need to avoid soy? Get the answer >>

Can vitamin K2 really help decrease calcium in the arteries? Get the answer >>

If vitamin K absorption appears to be reduced by other fat-soluble vitamins, like vitamin D, why do some "bone health" supplements combine them? Should they be taken separately? Get the answer >>

I am having trouble sleeping. I regularly take a multivitamin, fish oil, magnesium, calcium, vitamins D and K, and a protein supplement. I also take a low-dose blood pressure medication. Could any of these supplements be causing my insomnia? Get the answer >>

I've heard it's best to take fat-soluble supplements, like CoQ10, curcumin, and vitamin D, with fats or oils to increase absorption. Would taking them with a fish oil capsule be enough? Get the answer >>

Are the "% DV" numbers on vitamin supplement labels really based on what I need? Get the answer >>

Are there any supplements I should avoid when taking an antibiotic? Are there any that may be helpful? Get the answer >>

Is it true that overdoses of vitamin D only occur when you don't get enough vitamin K? Get the answer >>

Does taking a laxative interfere with the absorption of vitamins or minerals? Get the answer >>

Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins? Get the answer >>

What are natural remedies for coronavirus (COVID-19)? Do supplements like zinc, vitamin C, or herbals work? Get the answer >>
Join |  Sign In
Join Us on Facebook! Join Us on Instagram! Join Us on Twitter! Join Us on YouTube! Join Us on YouTube!
Product Reviews
Brands Tested
Health Conditions
CL Answers
Clinical Updates
Recalls & Warnings
Recommended Intakes
Where to Buy Products
Testing Program
How Products Were Tested
Quality Certification Program
Join CL Today
Join Free Newsletter
Group Subscriptions
Gift Membership
About Us
The CL Seal
CL Survey
Privacy Policy
Contact Us/Help

©2020, LLC. All rights reserved. A single copy of a report may be printed for personal use by the subscriber. It is otherwise unlawful to print, download, store or distribute content from this site without permission. name and flask logo are both registered trademarks of, LLC. This site is intended for informational purposes only and not to provide medical advice.