The Essential Trio: Understanding the Vitamin K, D, and Calcium Connection

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The Pure TheraPro Team

The Pure TheraPro Education Team is comprised of researchers from diverse backgrounds including nutrition, functional medicine, fitness, supplement formulation & food science. All articles have been reviewed for content, accuracy, and compliance by a holistic integrative nutritionist certified by an accredited institution.
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When it comes to maintaining healthy bones and optimal bodily functions, the synergy between vitamins K and D, alongside calcium, is indispensable. This trio works in a delicate balance, each element supporting the other to ensure our bodies function at their best. Let's delve into how these nutrients interact, their benefits, and considerations when supplementing them.

Vitamin D: The Sunshine Vitamin

Vitamin D is a fat-soluble vitamin crucial for the absorption and regulation of Calcium and Phosphorus, essential elements for maintaining healthy bone structure. Uniquely, it can be synthesized by the human body when the skin is exposed to sunlight.

Types of Vitamin D:

  • Vitamin D2 (Ergocalciferol): Primarily obtained through dietary sources such as fortified foods and plant-based supplements.
  • Vitamin D3 (Cholecalciferol): More effectively raises vitamin D levels in the blood and can be obtained through sun exposure, animal-based foods (like fatty fish and egg yolks), and supplements.

Vitamin D enhances Calcium absorption from the gut and maintains adequate serum Calcium and Phosphate levels, enabling normal mineralization of bones and preventing hypocalcemic tetany. It also plays roles in immune function and inflammation management.

According to data from the National Health and Nutrition Examination Survey (NHANES), about 42% of the American population has vitamin D deficiency (with many more having insufficient levels that don't quite meet the definition of a full-blown deficiency). This rate is higher among African Americans (82%) and Hispanics (69%), largely due to skin pigmentation reducing UV light absorption, which is necessary for the body to produce Vitamin D.

Symptoms of Vitamin D Deficiency:

  • Bone Pain and Muscle Weakness: These symptoms can be subtle but are often noticeable and can be attributed to inadequate Vitamin D levels, which are crucial for bone and muscle health.
  • Fatigue and General Malaise: Chronic tiredness that doesn’t improve with rest might be linked to insufficient Vitamin D.
  • Frequent Infections: Vitamin D plays a key role in the immune system, and low levels may lead to an increased risk of infections.
  • Depression or Mood Changes: There’s an established link between low Vitamin D levels and the risk of depression and other mood disorders.

Vitamin K: The Unsung Hero

Vitamin K, particularly in its K2 form, is crucial for bone health and blood coagulation. It activates proteins that regulate Calcium deposition, ensuring Calcium is directed towards the bones and away from arteries where it could cause harm. High vitamin K foods include leafy greens, such as kale and spinach, as well as fermented foods like natto.

Types of Vitamin K:

  • Vitamin K1 (Phylloquinone): Found primarily in green leafy vegetables, K1 is traditionally responsible for blood coagulation.
  • Vitamin K2 (Menaquinones): Produced by gut bacteria and found in fermented foods and some animal products, K2 is particularly effective in activating proteins that regulate calcium deposition in bones and teeth and preventing calcification of arteries and other soft tissues.

Symptoms of Vitamin K Deficiency

  • Easy Bruising and Bleeding: Vitamin K is essential for blood clotting. A deficiency might lead to more frequent bruising and bleeding episodes, such as nosebleeds or bleeding gums.
  • Excessive Menstrual Bleeding: Women may experience heavier than normal menstrual bleeding.
  • Blood in Urine or Stool: This can indicate severe deficiencies, leading to bleeding in internal organs or the gastrointestinal tract.
  • Osteoporosis or Reduced Bone Density: Vitamin K is important for bone health, and a deficiency can lead to weakened bones.

Calcium: The Building Block

Calcium is the most abundant mineral in the body, vital for building and maintaining strong bones and teeth. It also plays key roles in nerve transmission, muscle contraction, and cardiovascular health. However, surveys indicate that many Americans, particularly older women, do not meet these recommendations. Only about 32% of females and 51% of males meet the recommended intakes.

Forms of Calcium:

  • Calcium Citrate: Known for good absorption, this form does not require stomach acid for absorption, making it a preferable choice for older adults.
  • Calcium Carbonate: Requires stomach acid for absorption and is therefore best taken with food.

Symptoms of Calcium Deficiency

  • Muscle Cramps and Spasms: Hypocalcemia (low calcium levels) can cause muscle cramps, particularly in the back and legs.
  • Numbness and Tingling: People may feel these sensations around their mouth or in their fingers and toes.
  • Convulsions: Severe calcium deficiency can lead to seizures.
  • Confusion or Memory Loss: Calcium is vital for nervous system health, and its deficiency can affect cognitive functions.

Balancing the Trio: Why the Right Combination Matters?

The interplay between vitamin K, vitamin D, and calcium is complex. Vitamin K directs calcium into the bones and away from arteries, vitamin D enhances calcium absorption, and calcium builds and maintains bone structure. However, excessive supplementation of calcium and vitamin D, without adequate vitamin K, can lead to improper calcium deposition in arteries rather than bones.

Main Benefits of Adequate Vitamin D, Vitamin K, and Calcium Include:

  • Bone Health Support: Vitamin D and Vitamin K2 both enhance calcium absorption and direct its deposition to the bone, which can help improve bone density and reduce the risk of fractures.
  • Heart Health Support: Vitamin K2 reduces the risk of vascular calcification, a common issue when high levels of calcium are consumed without the balancing effect of Vitamin K.
  • Enhanced Absorption and Utilization: Vitamin D improves calcium absorption in the gut, while Vitamin K2 activates proteins that integrate calcium into bone and prevent its deposition in the arteries.

Why Supplementing Vitamin D and Calcium Alone Isn't Ideal?

The supplementation of calcium alongside vitamin D is a common practice aimed at preventing or treating osteoporosis and maintaining bone health. While these supplements can be beneficial, they are not without risks, especially when not balanced with other nutrients like vitamin K2.

Imbalanced Nutrient Absorption: Without adequate vitamin K2, the increased calcium absorbed due to vitamin D supplementation may deposit in arteries rather than bones, potentially leading to arteriosclerosis.

Associated Risks: Studies suggest that unbalanced supplementation of calcium and vitamin D can lead to an increased risk of heart disease and kidney stones, as excess calcium needs to be excreted by the kidneys.

Pure TheraPro’s Ultimate K2 is a cutting-edge, full-spectrum, liquid liposomal Vitamin K2 supplement formulated and manufactured in a cGMP & NSF-certified laboratory here in the USA.

We manufacture Ultimate K2 without any unnecessary ingredients such as added water, flavors, colors, or preservatives. 

Ultimate K2 is made with pure, liposomal, vegan MK-4 & MK-7 Vitamin K2 in a base of MCTs (medium chain triglycerides) from 100% organic coconut oil for enhanced absorption. Our phospholipid complex is derived from pure, non-GMO Sunflower Lecithin (no sunflower protein or lectins are present).

Forms: Includes two essential liposomal forms—MK-4 and MK-7.

MK-4 Vitamin K2 Source: Extracted from the geranium flower, ensuring high quality and bioavailability.

MK-7 Vitamin K2 Benefits: Provided in its bioactive 'trans' form MenaQ7®, which is pure and more effective than the commonly used 'cis' form.

Why Do You Need to Supplement with Vitamin K2?

Vitamin K2 insufficiency is widespread—even in healthy adults. To get the range of benefits that Vitamin K2 offers, you must take Vitamin K2 as a supplement, as food sources are limited at best.

K2 is critical to help your body ensure that the mineral Calcium is properly utilized so that it is delivered to your bones and does not end up in the heart and arteries where Calcium can cause harm.

This is why Vitamin K2 is especially important for those taking D3 & Calcium. Many people take Vitamin D3 and Calcium supplements thinking they're helping their bones… the truth is, without the addition of Vitamin K2, such a health regimen could prove dangerous.

Without adequate Vitamin K2, the body cannot properly direct Calcium to the bones where it's needed; instead, Calcium may often end up in soft tissue where it can lead to health problems.


Office of Dietary Supplements - National Institutes of Health. (n.d.). Vitamin A. Retrieved from

Office of Dietary Supplements - National Institutes of Health. (n.d.). Calcium. Retrieved from

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Lamson, D. W., & Plaza, S. M. (2003). The safety and efficacy of high-dose vitamin D3 and vitamin K2 in reducing calcium deposition in soft tissues. Alternative Medicine Review, 8(2), 125-134.

Rosen, C. J., & Adams, J. S. (2013). The Essential Nutrient Vitamin D: A Debunking of Common Myths About Vitamin D. Journal of Clinical Endocrinology & Metabolism, 98(6), E1283-E1301.

An Ballegooijen, A. J., & Pilz, S. (2017). The synergistic interplay between vitamins D and K for bone and cardiovascular health: A narrative review. International Journal of Endocrinology, 2017, 7454376.

Shea, M. K., & Holden, R. M. (2012). Vitamin K status and vascular calcification: Evidence from observational and clinical studies. Advances in Nutrition, 3(2), 158-165.

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