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Amid Confusion on Calcium Supplementation Safety, Vitamin K2 Study Offers Solution

<p>A recent article on vitamin K2 revealed new findings and an in-depth analysis of the nutrient&#8217;s use for promoting heart health when taken with calcium supplements. The results build on previous studies that have offered conflicting results regarding calcium safety and the possible risks to cardiovascular health upon supplementation.</p>

A recent article published in “Integrative Medicine" on vitamin K2 revealed new findings and an in-depth analysis of the nutrient’s use for promoting heart health when taken with calcium supplements. The results build on previous studies that have offered conflicting results regarding calcium safety and the possible risks to cardiovascular health upon supplementation.

The 2015 article, “Proper Calcium Use: Vitamin K2 as a Promoter of Bone and Cardiovascular Health," authored by Katarzyna Maresz, Ph.D., president and scientific coordinator, International Science and Health Foundation, revealed taking vitamin K2 can lower calcium-related health risks, such as an increased risk for heart disease. 1

Studies published in 2014 showed calcium supplementation did not increase heart disease risk or cause death in female subjects.2,3 However, Maresz’s article analyzed several different studies offering mixed messages on calcium safety, some of which show calcium supplementation did negatively affect cardiovascular health in certain populations.4,5,6

Research published in 2014 helped rebuild consumer confidence that calcium would not cause cardiovascular disease (CVD). However, various studies are showing mixed results on the issue.

“We need to remember that each study contains [a] different population, dose of calcium and time of supplementation, or even different statistical analysis," Maresz explained. She also said a number of studies have evaluated the risk of calcium supplementation, and because of the conflicting results, the link between calcium and heart disease should “at least be considered a concern."

This is where vitamin K2 comes in. In her recent article, Maresz explained how vitamin K2 acts as an inhibitor of arterial calcification and arterial stiffening, so consuming adequate amounts of the vitamin can lower the risk of vascular damage. This is because it activates matrix GLA protein (MGP), which works to prevent calcium deposits on blood vessel walls. People deficient in vitamin K experience inadequate activation of MGP, impairing the calcium removal process and increasing the risk of more serious issues, such as heart disease.

Maresz’s article explained how vitamin K2 content in today’s food supply has dropped significantly due to modern manufacturing practices, so supplementation can help consumers obtain the levels they need. A study published in 2015 on subjects supplementing with NattoPharma’s MenaQ7® vitamin K2 as MK-7 (menaquinone-7) demonstrated that supplementing with the nutrient can positively impact cardiovascular health.7 Researchers studied 244 healthy post-menopausal women, ages 55 to 65 years, for three years by using pulse wave velocity and ultrasound technologies. Participants took either 180 mcg/d of MenaQ7 during the three-year period, or placebo capsules. The study results confirmed the vitamin K2 supplement inhibited age-related arterial stiffening, and also significantly improved vascular elasticity.

“This cardiovascular study is significant because it shows that vitamin K2 not only benefits our bone health, but is also important to heart health," said Dennis Goodman, M.D., a board-certified cardiologist and director of integrative medicine at NYU Langone Medical Center, in a release from NattoPharma. Goodman further explained that flexibility of the arteries also has a direct connection to a person’s longevity. Calcification in the arteries can add 10 years to a person’s biological age.8

Manufacturers of both calcium and vitamin K2 should stay on top of the latest studies and realize more consumers are looking to research before purchasing products. “Whether positive or negative, these studies have an impact on how consumers view supplements, which are vital due to our nutrient-depleted diets," Maresz said. “As more science about the virtues of vitamin K2 is publicized, consumers will be seeking supplements that combine calcium and [vitamin] K2 … supplement manufacturers [should] make science part of their message."

Maresz added she has observed how consumers are actively educating themselves on vitamin K2, as demonstrated by interest in the educational portal, created to highlight research on the nutrient. She believes vitamin K2 will soon be recognized as a crucial partner to calcium, much like vitamin D, and supplement manufacturers can help make that connection for consumers.

Though the research behind calcium safety may cause confusion, studies on vitamin K2 prove that the nutrient can help mitigate the possible risk of vascular damage caused by calcium build up, making vitamin K2 an essential player in optimal bone and heart health.


1. Maresz K. “Proper Calcium Use: Vitamin K2 as a Promoter of Bone and Cardiovascular Health." Integrative Medicine: A Clinician’s Journal. 2015 Feb: 14(1).

2. Lewis JR et al. “The Effects of Calcium Supplementation on Verified Coronary Heart Disease Hospitalization and Death in Postmenopausal Women: A Collaborative Meta-Analysis of Randomized Controlled Trials." Journal of Bone and Mineral Research. 2014 July. doi: 10.1002/jbmr.2311

3. Pik JM et al. “Calcium supplement intake and risk of cardiovascular disease in women." Osteoporos Int. 2014 August. doi: 10.1007/s00198-014-2732-3

4. Xiao Q et al. “Dietary and supplemental calcium intake and cardiovascular disease mortality: the National Institutes of Health-AARP diet and health study." JAMA Intern Med. 2013;173(8):639-646.

5. Pentti K et al. “Use of calcium supplements and the risk of coronary heart disease in 52-62-year-old women: The Kuopio Osteoporosis Risk Factor and Prevention Study." Maturitas. 2009 May 20;63(1):73-78. doi: 10.1016/j.maturitas.2009.03.006. Epub 2009 Apr 24.

6. Li K, Kaaks R, Linseisen J, Rohrmann S. “Associations of dietary calcium intake and calcium supplementation with myocardial infarction and stroke risk and overall cardiovascular mortality in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition study (EPIC-Heidelberg)." Heart. 2012;98(12):920-925.

7. Knapen MH et al. “Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women: double-blind randomised clinical trial." Thromb Haemost. 2015 Feb 19;113(5).

8. Rosenhek et al. “Predictors of Outcome in Severe, Asymptomatic Aortic Stenosis." The New England Journal of Medicine." 2000; 343:611-617.

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