Product ReviewsVitamin K Supplements Review (Including Calcium and Vitamin D)
Initial Posting: 5/20/17 Last update: 6/8/17
Find the Best Vitamin K Supplement
See Which Vitamin K Supplements Passed CL's Tests & the Top Picks
Brands compared in report
 | AdvoCare Calcium Plus |
 | AlgaeCal Plus |
 | Carlson Vitamin K2 |
 | Doctor's Best Artery Prime With MenaQ7 |
 | Garden of Life Vitamin Code Raw K-Complex |
 | GNC K-2 |
 | Healthy Origins Natural Vitamin K2 As MK-7 |
 | Jarrow Formulas Bone-Up |
 | Nature's Way Alive Calcium Bone Formula |
 | NOW Vitamin D-3 & K-2 |
 | USANA Vitamin D |
 | Viactiv Calcium Plus D - Milk Chocolate |
More about this report
Can you trust your vitamin K supplement? ConsumerLab.com tests revealed some popular vitamin K supplements contained less vitamin K or another key ingredient, than claimed. One of these was also found to be contaminated with lead. Another product failed to disintegrate in the allotted time.
Fortunately, our tests also found several high quality products which can provide a significant dose of vitamin K for less than one cent per day. Among products which were Approved, ConsumerLab.com selected several Top Picks for providing the best quality and value.
In addition to its critical role in blood clotting, vitamin K may increase bone mineral density and reduce the risk of hip fracture when consumed with adequate intake of calcium and vitamin D. For this reason, vitamin K supplements have been clinically studied for aspects of bone health, as well as for other applications, such as cardiovascular health. Results of these studies, however, have been mixed.
You must be a member to get the full test results and quality ratings for twelve supplements with vitamin K -- eight selected for testing by ConsumerLab.com and four others that passed the same tests through CL's voluntary, Quality Certification Program.
In this comprehensive review, you'll discover:
In this comprehensive review, you'll discover:
- Which are the best-rated vitamin K supplements, and which failed our quality tests
- ConsumerLab.com's Top Picks among products
- Quality and cost comparisons to help you 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
Related questions and answers
- What is the difference between forms of vitamin K2? >>
- Do any supplements help prevent or treat osteoporosis? >>
- I'm considering taking vitamin K for my bones, but I take blood thinner (anti-coagulant) medication. Is there a problem taking both? >>
- Which supplements reduce the risk of stroke? Which increase the risk of stroke? >>
- Have you tested vitamin K supplements with MenaQ7? Is this a good source of vitamin K if I need to avoid soy? >>
- Can vitamin K2 really help decrease calcium in the arteries? >>
- 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? >>
- 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? >>
- 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? >>
- Are the "% DV" numbers on vitamin supplement labels really based on what I need? >>
- Are there any supplements I should avoid when taking an antibiotic? Are there any that may be helpful? >>
- Is it true that overdoses of vitamin D only occur when you don't get enough vitamin K? >>
- Does taking a laxative interfere with the absorption of vitamins or minerals? >>
- Is it better to get vitamins from foods or supplements, and are natural vitamins better than synthetic vitamins? >>