ConsumerLab.com uses JavaScript to provide the best possible experience for our content, but your browser has it disabled. Learn how to enable it here.

Home
/ Product Reviews
/ Vitamin K

Favorited

Not Favorited

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

Find Out If It's Worth Taking Vitamin K and Which Products Are Best

Latest Update

Statins & Vitamin K

Medically reviewed and edited by Tod Cooperman, M.D.

Updated September 03, 2024 ⓘ Expanded July 30, 2024 Published July 11, 2024

Vitamin K Review 2024

Watch the video

+— 38 sources

In addition the results of its expert testing, ConsumerLab uses only high-quality, evidence based, information sources. These sources include peer-reviewed studies and information from agencies such as the FDA and USDA, and the National Academy of Medicine. On evolving topics, studies from pre-print journals may be sourced. All of our content is reviewed by medical doctors and doctoral-level experts in pharmacology, toxicology, and chemistry. We continually update and medically review our information to keep our content trustworthy, accurate, and reliable. The following sources are referenced in this article:

Summary

What is vitamin K?
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 vitamin K 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 how to get vitamin K from food). Higher intakes of certain forms of vitamin K2 from food have been associated with a reduced risk of coronary artery calcification and mortality from coronary heart disease. Vitamin K supplements, typically at high doses, have been clinically evaluated to see if they increase bone density, reduce fractures, or reduce coronary artery calcification and improve cardiovascular function, but results have been mixed, so it is not clear that supplementation will help (see What It Does).
Which form of vitamin K is best?
There are several forms of vitamin K. All are active, but one, the MK-7 form of vitamin K2, has a longer-half life than vitamin K1 and the MK-4 form of K2, so that smaller doses may be used (see What It Is and What to Consider When Buying).
What did CL's tests of vitamin K supplements find?
Among the vitamin K supplements selected and purchased by ConsumerLab for testing, one contained only 80.8% of its listed vitamin K and another contained much more vitamin D than listed. The other products passed CL's tests, including several tested through CL's Quality Certification Program, (see What CL Found).
Which vitamin K supplement is best?
Among the vitamin K supplements that CL tested and Approved for Quality (see What CL Found), CL selected Top Picks based quality, dosage, and price, for vitamin K1 as well the MK-4 and MK-7 forms of vitamin K2, some of which include vitamin D, calcium, and/or magensium. (In addition to the products tested in this review, other products discussed include Jarrow BoneUp and Naturelo Bone Strength.).
How much vitamin K should I 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 most 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 doses, e.g., 180 mcg (see What to Consider When Using)
How to take vitamin K:
Vitamin K is fat soluble, so you'll absorb more of it when you take it with a meal that has fats or oils. However, because other fat-soluble vitamins, such as vitamin D, can compete with vitamin K for absorption, it's best to take vitamin K at least 3 hours apart from vitamin D (see What to Consider When Using). [Note: Many bone health supplements contain vitamins K and D together, but there is no need for this. Also, vitamin K does not lower the risks associated with taking high-dose vitamin D or prevent vitamin D overdose.]
Vitamin K safety and side effects:
Vitamin K is fairly safe. However, it can interact with certain medications, including blood-thinning drugs. If you have an allergy to soy, be aware that most MK-7 forms of vitamin K are derived from soy — although one brand is derived from chickpeas (see Concerns and Cautions).

Make sure you're choosing the best vitamin K supplements approved in our tests!

See the Full Review as a Member

Join now at www.consumerlab.com/join/

Alphabetical list of vitamin K supplements compared in this review

AlgaeCal Plus

Bluebonnet_Vitamin_K1_100_mcg-Bone_Health-2024-small.png

Bluebonnet Vitamin K1 100 mcg

Bronson Vitamin K2

Carlson_Super_Daily_D3_plus_K2-Bone_Health-2024-small.png

Carlson Super Daily D3 + K2

Healthy_Origins_Natural_Vitamin_K2_as_MK-7-Bone_Health-2024-small.png

Healthy Origins Natural Vitamin K2 as MK-7

Innovixlabs_Full_Spectrum_Vitamin_K2-Bone_Health-2024-small.png

Innovixlabs Full Spectrum Vitamin K2

Innovixlabs_Vitamin_D3_plus_K2-Bone_Health-2024-small.png

Innovixlabs Vitamin D3 + K2

Life_Extension_Bone_Restore_Calcium_Supplement_with_Vitamin_K2-Bone_Health-2024-small.png

Life Extension Bone Restore Calcium Supplement with Vitamin K2

Life_Extension_Vitamins_D_and_K_with_Sea-Iodine-Bone_Health-2024-small.png

Life Extension Vitamins D and K with Sea-Iodine

New_Chapter_Plant_Calcium_Bone_Strength_Take_Care-Bone_Health-2024-small.png

New Chapter Plant Calcium Bone Strength Take Care

Sports Research D3 + K2

Thorne Vitamin D + K2

You must be a member to get the full test results along with ConsumerLab.com recommendations and quality ratings. You will get results for 12 vitamin K supplements, including seven selected for testing by ConsumerLab.com and five 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 -- -- including combinations with vitamin D
ConsumerLab.com'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

Join to unlock the full report and get full access to over 1,400 reviews

See the Full Review as a Member

Join now at www.consumerlab.com/join/

Related CL Answers (16)

Load More…

Join over 250,000 people on our weekly email list.

Featured In

Good Housekeeping

Eat Right

People's Pharmacy

Reader's Digest

US News

OUR MISSION: To identify the best quality health and nutritional products through independent testing.

Join Now & Get Full Access