The Two Forms of Vitamin K and Why You Need Them

Updated: June 7, 2023

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Lara Pizzorno is the author of “Your Bones: How You Can Prevent Osteoporosis and Have Strong Bones for Life – Naturally” and a member of the American Medical Writers Association with 29 years of experience specializing in bone health.

Recently we asked Lara if she would help us provide a series of short, ongoing videos to help you (our customers and readers) stay up to date on the latest facts and science related to bone health.

In this latest video, Lara discusses the two different types of vitamin K2 and why you need each. Watch the video below (or read the transcript provided) and let us know what you think in the comments. 🙂

Hello, my name’s Lara Pizzorno. I’m the author of “Your Bones” and I’m here to share with you some information that I hope will help you to have healthier bones. In this series of videos we’re talking about Vitamin K in both its form, K1 and K2. And in this video we’ll be covering the first topic that I mentioned in the overview video which is Vitamin K in both its forms. K1 and K2 plays a number of critical roles in your bones’ health.

Very briefly, K1 has powerful anti-inflammatory actions.

When you get too little K1 from your diet, your inflammation goes up, and anything that promotes inflammation will also lead to excessive osteoclast activation and bone loss. Remember, the osteoclasts are the specialized cells in our bodies that break down old bone so that it can be replaced with new bone. But when they get activated too frequently, we lose too much bone to replace it quickly enough.

Too little K1 will result in inflammation occurring in your body, and when your body is inflamed, even a chronic low grade inflammation, your osteoclasts are activated and this promotes bone loss. Both Vitamin K1 and K2 are the co-factors for very different but very important enzymes. Without K1 and K2 inserted into these enzymes, they don’t work, and when they don’t work they’re unable to activate some very important proteins. So those don’t work either.

The biochemistry is pretty complicated, but you don’t have to know all the steps involved to understand that:

  1. Vitamin K1 is required to activate the proteins better involved in blood clotting,
  2. and Vitamin K2 is required to activate the proteins that determine where calcium goes in our bodies, making sure that the calcium we absorb goes into our bones where we want it and not into our arteries or our hearts where we don’t. That’s the job of the proteins activated by K2.

One of these proteins called osteocalcin pulls calcium into our bones and another called matrix-Gla protein actively prevents calcium from depositing in soft tissues, not only our arterieheart-failure-new-chapter-bone-supplements-for-bone-healths and hearts but our kidneys, breasts, and brain where we certainly don’t want calcium deposits. The latest research is actually even showing on its animal studies still, but it’s showing, that Vitamin K2 can even remove calcium that is already deposited in the cardiovascular system. So too little K2 can result in calcium depositing where we don’t want it in soft tissue, like our blood vessels instead of in our bones.

You may remember back in 2011 hearing results from an analysis of the data from the Women’s Health Initiative study that taking calcium and Vitamin D might actually even increase your risk for having a heart attack.

When this paper was published, it initiated a press feeding frenzy, and lots of articles came out and scared a lot of us from taking enough calcium and Vitamin D that we needed to have healthy bones.

What was really going on here?

Well, we certainly have to have calcium and Vitamin D. We have to have Vitamin D to absorb the calcium. So obviously there was some other factor that was missing, and now just from listening to the few things I have explained to you about Vitamin K, you know that Vitamin K2 activates the proteins that are responsible for regulating where calcium goes, putting it into bone and preventing it from depositing in our hearts or arteries. So you, unlike the doctors who conducted this study, can probably figure out what was wrong.

The women in this study were not taking Vitamin K2, they were only taking calcium and Vitamin D.

So the calcium that they were absorbing was not being regulated into where it was going. It’s not surprising that it could have caused problems.

Not only does Vitamin K2 regulate where calcium goes in your body, but Vitamin K2 and Vitamin D work together, they’re a team.

Vitamin D increases both our body’s ability to absorb calcium, and at the same time Vitamin D also increases our body’s production of Vitamin K dependent proteins, osteocalcin and matrix-Gla protein. Osteocalcin which puts calcium when we want it and matrix-Gla protein which keeps it out of the places where we don’t want it.

Our bodies come pre-programmed to keep us healthy. Your body knows automatically that Vitamin D will only increase your absorption of calcium but do nothing to regulate where that calcium goes. Your body knows that that is the job of Vitamin D’s partner, K2. Your body is pre-programmed for this partnership. When you take Vitamin D, your body automatically produces more of the Vitamin K dependent proteins, osteocalcin and matrix-Gla protein, so that the increased calcium you will be absorbing is going to be put in the right place.

This, however, can only happen when you provide your body, not only with calcium and Vitamin D, but with the K2 that it has to have to activate ostecalcin and matrix-Gla protein. So that’s the quick overview. To have healthy bones, we must have Vitamin K, and we need it in both its forms, K1 and K2.

In our next video we’ll start talking in detail about Vitamin K1 and all the ways in which it helps us to have healthy bones. And we’ll also discuss what happens when we don’t get enough Vitamin K1. Thanks for tuning in. I hope this has been helpful for you.


El Asmar MS, Naoum JJ, Arbid EJ. Vitamin k dependent proteins and the role of vitamin k2 in the modulation of vascular calcification: a review. Oman Med J. 2014 May;29(3):172-7. doi: 10.5001/omj.2014.44. PMID: 24936265

Flore R, Ponziani FR, Di Rienzo TA, et al. Something more to say about calcium homeostasis: the role of vitamin K2 in vascular calcification and osteoporosis. Eur Rev Med Pharmacol Sci. 2013 Sep;17(18):2433-40. PMID: 24089220

Wahlqvist ML, Tanaka K, Tzeng BH. Clinical decision-making for vitamin K-1 and K-2 deficiency and coronary artery calcification

Theuwissen E, Smit E, Vermeer C. The role of vitamin K in soft-tissue calcification. Adv Nutr. 2012 Mar 1;3(2):166-73. doi: 10.3945/an.111.001628. PMID: 22516724

Schurgers LJ, Uitto J, Reutelingsperger CP. Vitamin K-dependent carboxylation of matrix Gla-protein: a crucial switch to control ectopic mineralization. Trends Mol Med. 2013 Apr;19(4):217-26. doi: 10.1016/j.molmed.2012.12.008. Epub 2013 Jan 30. PMID: 23375872

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van den Heuvel EG, van Schoor NM, Lips P, Magdeleyns EJ, Deeg DJ, Vermeer C, den Heijer M. Circulating uncarboxylated matrix Gla protein, a marker of vitamin K status, as a risk factor of cardiovascular disease. Maturitas. 2014 Feb;77(2):137-41. doi: 10.1016/j.maturitas.2013.10.008. Epub 2013 Oct 24. PMID: 24210635

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Article Comments

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  1. Rachel Bossie

    September 22, 2015 , 7:05 am

    Great introduction to Vitamin K and spoken clearly in understanding terms; very informational. Thank you.

  2. Rachel Bossie

    September 22, 2015 , 7:09 am

    Thank you for the enlightening facts and helpful information on Vitamin K and spoken in clear and understanding terms. I look forward to listening to your other videos.

  3. Clemie

    November 28, 2019 , 10:28 am

    I apresiate your information about K1 and K2. I am already taking Vitamin K2 with Vitamin D3. Thank you.

  4. Blaire AlgaeCal

    November 29, 2019 , 8:50 am

    So glad you found this information helpful, Clemie! ?

    – Blaire @ AlgaeCal

  5. Mary

    October 9, 2022 , 6:44 am

    Is K1&K2 in one pill

  6. Brianne Bovenizer

    October 9, 2022 , 9:17 am

    Hi Mary,

    Thanks so much for your comment! AlgaeCal Plus contains only vitamin K2, however you may be able to find a combination if you check out your local health food store! That said, K1, unlike K2, is much easier to obtain from you diet. Some great food sources for this include dark leafy greens, such as kale, spinach and collard greens!

    I hope this helps! 🙂

    – Brianne @ AlgaeCal

  7. Stacy Harris

    November 10, 2022 , 3:54 am

    I stumbled upon this video because I was researching why I brushed so easily. One of this first reasons that popped up was a deficiency of vitamin K. I clicked on that link which led me to this video. I had researched in the past about my problems with easy brushing and I bought a supplement with k2/d3. I really didn’t totally understand the relationship in taking those two supplements together until NOW. This video explained in detail the reason why you need both vitamins and calcium(which I also take) to get the benefits of these supplements. Thanks so very much for publishing this video. Many more women need to be educated about how important these vitamins are and to start taking them at an early age to help prevent osteoporosis, inflammation and bruising.

  8. Chelsea Dugas

    November 11, 2022 , 11:21 am

    Thank you for your feedback, Stacy! We’re happy this information has provided another piece of the puzzle to your health. Please know that our Bone Health Consultants are available 7 days a week at 1-800-820-0184 (USA & Canada, toll-free) or by email at [email protected] to answer all your questions and provide personalized support! 🙂

    – Chelsea @ AlgaeCal

  9. Marion Zola

    May 3, 2023 , 8:54 pm

    I have been taking algae CAL plus and strontium for years. I also exercise. I do Pilates, classes online with the save Institute and walking. Nonetheless, in January, I fell off an elevated place onto a stone floor, where I broke my femur. Despite good DEXA scans, my doctor says that if I broke a bone, I automatically have osteoporosis. What do you think of this comment?

  10. Yoori AlgaeCal

    May 7, 2023 , 3:30 pm

    We are sorry to hear of your fracture, Marion! I hope you got all the support you need and you’re recovered by now.

    Marion, my understanding is that while you’re prone to more fractures when you have bone loss, it doesn’t necessarily mean that if you broke a bone, you automatically have bone loss. The best way to find out if you have bone loss would be through a DEXA scan. I recommend clarifying this with your physician! 🙂

    – Yoori @ AlgaeCal

  11. Diana Cosgrove

    May 17, 2023 , 9:28 am

    I never knew that the two sources of vitamin k had such different functions and that both were needed for healthy bones. Thank you for sharing this information.

This article features advice from our industry experts to give you the best possible info through cutting-edge research.

Lara Pizzorno
MDiv, MA, LMT - Best-selling author of Healthy Bones Healthy You! and Your Bones; Editor of Longevity Medicine Review, and Senior Medical Editor for Integrative Medicine Advisors.,
Dr. Liz Lipski
PhD, CNS, FACN, IFMP, BCHN, LDN - Professor and Director of Academic Development, Nutrition programs in Clinical Nutrition at Maryland University of Integrative Health.,
Dr. Loren Fishman
MD, B.Phil.,(oxon.) - Medical Director of Manhattan Physical Medicine & Rehabilitation and Founder of the Yoga Injury Prevention Website.,
Prof. Didier Hans
PHD, MBA - Head of Research & Development Center of Bone Diseases, Lausanne University Hospital CHUV, Switzerland,