What is the most underrated vitamin? Exploring the Power of Vitamin K2

October 5, 2025 •

3 min read

While many focus on well-known nutrients like vitamin C and D, the 2004 Rotterdam Study found that long-term intake of a specific vitamin was linked to a 50% reduction in arterial calcification. This powerful insight suggests that a quiet nutritional powerhouse, known as Vitamin K2, may be what is the most underrated vitamin in your diet.

Quick Summary

Vitamin K2, a fat-soluble nutrient often overlooked in Western diets, plays a critical role in directing calcium to the bones and away from the arteries, promoting superior cardiovascular and skeletal health.

Key Points

Calcium Traffic Controller: Vitamin K2 is vital for directing calcium to the bones and teeth while preventing its buildup in arteries and soft tissues.
Cardiovascular Protector: It activates Matrix Gla Protein (MGP), an inhibitor of vascular calcification, significantly reducing the risk of heart disease.
Bone Strengthener: K2 works with Vitamin D to activate osteocalcin, a protein that binds calcium to bones, crucial for mineralization and density.
Brain and Nerve Function: Studies suggest K2 and Choline play important roles in brain health, cognitive function, and the nervous system.
Hidden Deficiency: K2 is scarce in modern Western diets, making deficiency common and its health consequences often overlooked.
Synergy with Other Nutrients: K2 works synergistically with Vitamin D, while Magnesium is essential for activating Vitamin D, highlighting the importance of nutrient teamwork.

The Case for Vitamin K2: The Calcium Director

While vitamins like C, D, and the B-vitamins are widely recognized, Vitamin K2 (menaquinone) is a crucial nutrient that often goes unnoticed, yet is vital for long-term health. Unlike vitamin K1 (phylloquinone), which is known for blood clotting, K2's primary function is to regulate calcium. It activates proteins that guide calcium to bones and teeth, preventing its harmful accumulation in soft tissues like arteries. This unique action makes K2 a key factor in preventing age-related diseases linked to calcium imbalance.

Heart Health: Protecting Your Arteries

Arterial calcification, a major risk factor for heart disease, involves calcium buildup in artery walls, leading to stiffness. Vitamin K2 is essential here, activating Matrix Gla Protein (MGP), a powerful inhibitor of soft tissue calcification. Insufficient active MGP allows calcium to build up in arteries. The Rotterdam Study indicated that higher dietary K2 intake was associated with a 50% lower risk of death from heart disease related to hardened arteries.

Bone Strength: The Missing Link

Calcium and vitamin D are known for bone health, but vitamin D mainly aids calcium absorption. Vitamin K2 complements this by activating osteocalcin, which binds calcium to the bone matrix, improving strength and density. The synergy between D and K2 is vital for optimal bone health. Some research suggests K2 supplements can reduce fractures and improve bone quality, and in some countries, K2 is used as an osteoporosis treatment.

Dental Health: The Connection to Your Smile

K2's role in activating osteocalcin also benefits dental health by building and repairing dentin. This helps protect against decay. A review found K supplementation and fiber intake were effective in preventing tooth loss from periodontal disease in older adults.

Beyond the Basics: Other Potential Benefits

Vitamin K2 is also being studied for other benefits:

Brain Function: Potential neuroprotective effects and influence on brain myelination.
Sexual Health: Potential to stimulate testosterone production and improve erectile function.
Insulin Sensitivity: Linked to improved insulin sensitivity and lower type 2 diabetes risk.

How to Get Your Vitamin K2

Unlike K1 in leafy greens, K2 is less common in Western diets. Good sources include:

Natto: A top source of MK-7.
Goose Liver Pâté: Highly concentrated.
Fermented Dairy: Hard cheeses like Gouda.
Eggs: Especially from pasture-raised chickens.
Meat: Organ meats and grass-fed cuts.

Vitamin K1 vs. Vitamin K2: A Comparison


Feature	Vitamin K1 (Phylloquinone)	Vitamin K2 (Menaquinone)
Primary Role	Blood clotting.	Calcium regulation, bone and heart health.
Food Sources	Green leafy vegetables.	Fermented foods, grass-fed animal products.
Absorption	Rapid, short-lived.	Slower absorption, longer half-life (MK-7).
Bodily Function	Liver clotting factors.	Bone mineralization, arterial elasticity.

Giving K2 its Due

Vitamin K2 is an underappreciated nutrient with significant health benefits. Its ability to manage calcium in the body supports both bone and cardiovascular health. Ongoing research indicates its impact on brain, dental, metabolic, and endocrine functions. Due to its scarcity in Western diets, incorporating K2-rich foods or supplements is important for long-term health. Understanding what is the most underrated vitamin and ensuring adequate intake is a valuable investment in health.

Other Overlooked Nutrients: More Than Just K2

Beyond K2, other nutrients like Choline and Magnesium are often overlooked. Choline is crucial for brain, liver, and metabolic function, yet many don't get enough. Vitamin D's benefits extend to immunity and mood. Magnesium is a vital cofactor for many enzymes and activates Vitamin D. These nutrients highlight the need for a comprehensive dietary approach.

Conclusion: Making Informed Choices

Nutritional science is dynamic, and the importance of nutrients like Vitamin K2, Choline, and Magnesium is becoming clearer. A balanced diet rich in diverse foods is the best approach. For specific needs, targeted supplementation, with professional guidance, can be beneficial.

To learn more about Vitamin K2, see: The Hidden Benefits of Vitamin K2: A Doctor Reveals What You Need to Know.

Frequently Asked Questions

Vitamin K1 is primarily involved in blood clotting and is found in leafy greens. Vitamin K2, found in fermented foods and grass-fed animal products, regulates calcium metabolism to support bone and heart health.

MK-7 has a longer half-life and remains in the bloodstream for a longer period, while MK-4 is rapidly absorbed. While both are beneficial, MK-7 is often favored for supplementation due to its longer availability.

The richest source of K2 is natto (fermented soybeans). Other sources include goose liver pâté, hard cheeses like Gouda and Brie, and eggs from pasture-raised chickens.

Many Western diets are deficient in K2. While consuming fermented and grass-fed products helps, supplementation may be necessary to reach optimal intake levels, especially for certain health goals.

Individuals on anticoagulant medications like warfarin should consult their doctor before taking K2 supplements. K2 can interfere with blood-thinning medications.

While overt symptoms are rare, long-term deficiency can manifest as hidden bone loss and vascular damage over time. Increased bruising or bleeding can be a more direct sign of general Vitamin K deficiency.

Vitamin D helps the body absorb calcium, but Vitamin K2 is necessary to activate the proteins that direct that calcium to bones and teeth. Without K2, the absorbed calcium may deposit in arteries instead.