Unveiling Vitamin K’s Underrecognized Benefits for Bone Health

• Vitamin K1 (phylloquinone) supports vascular health and bone retention — This form of vitamin K reduces calcification in blood vessels while helping bones retain calcium, preventing unnecessary calcium buildup in the arteries.

• Vitamin K2 (menaquinone) activates vitamin D and directs calcium — K2 works by activating vitamin D-dependent proteins, allowing calcium to be efficiently transported out of the arterial system and into bones and teeth.²

• Vitamin K is vital for the carboxylation of osteocalcin — This is a process that enhances bone strength. It might sound complex, but it’s actually a straightforward process. To understand this, you must first know what osteocalcin is — this is a small protein produced by osteoblasts during bone formation.³

• Carboxylation transforms osteocalcin into a functional hormone — Carboxylation is a process wherein osteocalcin is transformed from a simple protein into a sophisticated hormone involved in bone metabolism and broader metabolic regulation.

When your body lacks sufficient vitamin K, the carboxylation of osteocalcin is impaired. This means that osteocalcin cannot effectively bind calcium to the bone matrix. Over time, this contributes to osteoporosis, where bones become porous and more prone to fractures.

• Vitamin K deficiency increases cardiovascular risk — When calcium is not directed to your bones where it’s needed most, it not only decreases bone mineral density and increases fragility, but also puts you at risk of cardiovascular conditions. This is because calcium accumulates in places like your blood vessels and arteries instead.

• Common causes of vitamin K deficiency — The underlying causes of vitamin K deficiency often stem from poor dietary intake, certain medical conditions or the use of medications that interfere with vitamin K absorption. For instance, individuals with gastrointestinal disorders struggle to absorb this nutrient effectively. Additionally, long-term use of antibiotics disrupts gut bacteria, reducing your body’s natural production of vitamin K.

• Vitamin K activates key bone-building proteins — Vitamin K facilitates the carboxylation of osteocalcin and matrix Gla-protein (MGP), which are essential for binding calcium within the bone matrix. MGP is also a potent inhibitor of arterial calcification.

• Vitamin K enables calcium-binding through carboxylation — One of the researchers’ key findings was that vitamin K acts as a necessary cofactor for enzymes that convert glutamic acid residues in proteins into gamma-carboxyglutamic acid residues. This chemical transformation is important for osteocalcin to effectively bind calcium. According to the researchers:

“The important effects of vitamin K on Ca and skeletal homeostasis are known to be mediated through its role as a cofactor for the γ-glutamyl carboxylase enzyme that promotes conversion of glutamate (Glu) residues to gamma-carboxyglutamic (Gla) residues in the post-translational carboxylation of osteocalcin (OC) and matrix Gla protein (MGP). This may have a significant impact on osteogenesis.”⁵

• Vitamin K2 plays a key role in bone remodeling — The study also revealed that vitamin K2 plays a significant role in bone remodeling. It assists in directing calcium to the bones and prevents its deposition in soft tissues, which leads to vascular calcification. This dual action supports both bone and cardiovascular health.

• Vitamin K and vitamin D work together to regulate calcium balance — The research highlighted the synergistic relationship between vitamins K and D in regulating calcium homeostasis.

Vitamin D enhances calcium absorption in the gut, while vitamin K ensures that the absorbed calcium is appropriately utilized by the bones. This collaboration between the two vitamins is essential for maintaining optimal bone density and reducing the risk of fractures.

“Vitamin D exerts effects directly on osteoblasts by promoting osteoblast maturation and OC synthesis. The multiple effects of vitamin D on bone are associated with a high expression of the vitamin D receptor in several types of bone cells.”⁶

• Researchers identified biomarkers for vitamin K status — The ratio of carboxylated osteocalcin (cOC) to undercarboxylated osteocalcin (ucOC) was used to assess functional vitamin K levels in the body. A lower cOC-to-ucOC ratio indicated an inadequate vitamin K status, which was associated with increased bone loss and a higher risk of hip fractures.

• Vitamin K is essential for both bone integrity and metabolic health — The study focused on individuals with varying levels of vitamin K intake, analyzing their bone integrity and insulin sensitivity. Findings revealed that adequate vitamin K levels are essential for maintaining strong bones and regulating blood sugar levels, highlighting this nutrient’s importance in inhibiting conditions like osteoporosis and diabetes.

• Osteocalcin links vitamin K to both bone and glucose metabolism — Activated osteocalcin contributes to bone strength and influences how the body regulates insulin and blood sugar levels. This dual function means that vitamin K deficiency could lead to both weakened bones and impaired glucose metabolism, heightening the risk of developing diabetes.

“[V]itamin K deficiency in the bone results in a lower production of OC and a low serum level of OC, predisposing to a state of glucose intolerance and diabetes mellitus that may then enhance bone matrix deterioration via the production of cross-linked advanced glycation end products (AGE), which have been further associated with bone fractures after adjustment of confounders.

We believe that as a whole, vitamin K deficiency plays an important role in glucose metabolism, ultimately leading to a disturbance of bone quality,” the researchers reported.⁸

• Vitamin K prevents arterial calcification and cardiovascular disease — In addition to its effects on bone and energy metabolism, vitamin K was found to play a role in preventing the calcification of soft tissues, such as blood vessels. This prevents the hardening of arteries, which is a significant risk factor for cardiovascular diseases. The research emphasized that vitamin K ensures calcium is directed to the bones rather than accumulating in the arteries

• Uncarboxylated osteocalcin (ucOC) is a marker of vitamin K deficiency — The study identified specific markers for vitamin K deficiency, such as elevated levels of uncarboxylated osteocalcin (ucOC) in the blood. Monitoring these markers will help in early detection of vitamin K insufficiency, allowing for timely interventions to maintain bone density and metabolic health.

• Low vitamin K intake is linked to a higher risk of fractures — Individuals with low vitamin K intake were found to have a higher incidence of hip and vertebral fractures across different populations. The research underscored the importance of maintaining adequate vitamin K levels through diet or supplementation to significantly reduce the risk of such fractures.

• Gut bacteria naturally produce vitamin K2 — The research focused on understanding how variations in the gut microbiome affect the risk of developing bone-related conditions such as osteoporosis. It was found that certain beneficial gut bacteria species, like Bacteroides and Lactococcus lactis, produce vitamin K2 and help maintain adequate levels of this nutrient.

• Dysbiosis lowers vitamin K2 levels, weakening bones — One of the key findings was that disruptions in the gut microbiome, a condition known as dysbiosis, decreases your vitamin K2 production,¹⁰ compromising bone strength and increasing your risk of fractures and osteoporosis.

Vitamin K2 produced by gut bacteria activates proteins that are essential for bone formation and mineralization, and maintaining a balanced and healthy gut microbiome is essential for ensuring the proper synthesis of vitamin K2.

• Probiotics and prebiotics enhance bone health —The review also discussed the role of probiotics and prebiotics in enhancing bone health. Probiotics are live beneficial bacteria that are consumed through fermented foods or supplements, while prebiotics are non-digestible food ingredients that promote the growth of these healthy bacteria.¹¹

Incorporating probiotics and prebiotics into your diet supports your gut microbiome, leading to increased production of vitamin K2 and improved bone density.

• The gut microbiome supports calcium and vitamin D absorption — The study also highlighted the interconnectedness between the gut microbiome and other aspects of bone metabolism, such as hormone regulation and immune system function.

Your gut bacteria influence the absorption of calcium and vitamin D as well, both of which are vital for bone health. Additionally, a healthy gut microbiome helps modulate the immune system, reducing inflammation that negatively impacts bone integrity.

• Antibiotics disrupt vitamin K2 production — The review also pointed out that antibiotic treatments, which disrupt the gut microbiome, lead to a significant reduction in vitamin K2 production.¹² This not only affects bone health but also emphasizes the importance of being cautious when taking antibiotics, to preserve the beneficial bacteria responsible for maintaining bone integrity.

• Egg quality is important — You need to be careful about your egg sources as most commercial egg sources — even free-range organic — have high PUFA levels as they are fed grains like soy and corn.

• Chickens should be fed low-PUFA grains for optimal egg quality — Ideally, chickens should be fed rice, barley and split peas. I personally eat six egg yolks a day from chickens who are fed this and have 80% less linoleic acid than regular chickens.

1. Add more green leafy veggies into your diet — They are some of the best sources of vitamin K1. Collard and turnip greens, kale, spinach, broccoli, Brussels sprouts, cabbage and lettuces are good choices.¹³

2. Boost your natural vitamin K2 production — Enhance your body’s natural vitamin K2 levels by incorporating fermented foods such as natto and fermented vegetables cultivated with specific bacterial cultures. Additionally, consume grass fed animal products like egg yolks, liver and grass-fed dairy to support K2 production.

3. Optimize your vitamin K2 supplementation — Supplement with 180 to 200 micrograms of vitamin K2, ideally in the MK-7 form, daily, combined with 1,000 IU of vitamin D3 and 400 mg of magnesium. This combination ensures optimal absorption and effectiveness, working synergistically to strengthen bones while protecting against arterial calcification.

You should also time your vitamin K2 intake strategically. Take vitamin K2 supplements with your fattiest meal of the day since it’s fat-soluble. This maximizes absorption and allows vitamin K2 to activate osteocalcin. Consistent timing helps maintain steady levels of vitamin K2 for optimal bone and heart protection.

4. Balance key nutrient cofactors — Ensure sufficient intake of calcium, magnesium, vitamin D3 and vitamin K2 through both diet and supplementation. These nutrients collaborate to build and maintain bone density, promoting proper calcium utilization and bone matrix formation for optimal bone health.

5. Support your gut microbiome — Maintain a healthy intestinal environment to naturally boost vitamin K2 production. Focus on whole, unprocessed foods and consider targeted probiotic supplementation tailored to your microbiome.

6. Focus on bone-building exercises — Regular weight-bearing movement stimulates bone formation while K2 ensures proper calcium deposition. Walking, resistance training and bodyweight exercises work together with K2 to strengthen your skeleton. The combination reduces fracture risk far more than supplementation alone.