What are the benefits of vitamin K?

December 2, 2025 •

3 min read

Many people know vitamin K is essential for blood clotting, a fact established in 1929 when Danish scientist Henrik Dam discovered the "Koagulationsvitamin". However, the benefits of vitamin K extend far beyond coagulation, playing crucial roles in bone health, heart health, and more.

Quick Summary

Vitamin K is a fat-soluble vitamin crucial for blood clotting, bone mineralization, and preventing arterial calcification. Higher dietary intake supports strong bones and cardiovascular health.

Key Points

Crucial for Coagulation: Vitamin K activates proteins essential for blood clotting and wound healing, preventing excessive bleeding.
Supports Bone Strength: It helps activate osteocalcin, a protein that binds calcium to build and maintain strong bones, and may lower fracture risk.
Protects Heart Health: Vitamin K prevents arterial calcification by activating Matrix Gla Protein (MGP), helping to keep blood vessels flexible.
K1 vs. K2: Vitamin K1 from plants primarily supports blood clotting, while Vitamin K2 from animal and fermented foods is crucial for bone and heart health.
Deficiency Is Rare But Possible: While most get enough from diet, certain medical conditions can cause a deficiency, most notably in newborns who require a prophylactic injection.
Interacts with Medications: Individuals on blood-thinning medication like warfarin must monitor their vitamin K intake to avoid dangerous interactions.

Vitamin K is an essential fat-soluble nutrient, most famously known for its pivotal role in blood coagulation. This function was discovered in 1929 and initially defined the vitamin. However, research has revealed a wider range of benefits for this nutrient. These benefits stem from vitamin K's role in activating specific proteins throughout the body. These proteins are involved in processes like bone formation and regulating calcium in arteries. There are two main natural forms: K1 (phylloquinone) in plants, and K2 (menaquinone) in animal and fermented foods, also produced by gut bacteria.

The Foundational Role in Blood Clotting

Vitamin K is necessary for the body to form blood clots effectively. It activates several proteins in the coagulation cascade, such as prothrombin. This process is crucial for wound healing. Newborns often receive a vitamin K injection due to low levels and risk of bleeding. People taking blood thinners like warfarin need to manage their vitamin K intake as it affects the medication's action.

Strengthening Bones and Preventing Osteoporosis

Vitamin K is also vital for bone health. It activates osteocalcin, a protein that helps incorporate calcium into bone, increasing density and strength. Higher intake, especially of K2, has been linked to fewer fractures and better bone density, particularly in postmenopausal women. A form of K2 (MK-4) is even used to treat osteoporosis in some countries.

Supporting Heart Health and Arterial Elasticity

Vitamin K helps prevent calcium buildup in arteries, known as arterial calcification. It does this by activating Matrix Gla Protein (MGP), which inhibits soft tissue calcification. Preventing this buildup helps maintain blood vessel elasticity, supporting healthy blood flow. Vitamin K2 has been associated with a lower risk of heart disease.

The Difference Between Vitamin K1 and K2

Though similar, K1 and K2 differ in sources, function, and how long they stay in the body.


Feature	Vitamin K1 (Phylloquinone)	Vitamin K2 (Menaquinone)
Primary Source	Plant foods, especially leafy greens like kale, spinach, and broccoli.	Animal products (meats, dairy, eggs) and fermented foods like natto.
Main Function	Acts primarily in the liver to activate proteins for blood clotting.	Acts predominantly outside the liver, crucial for bone and arterial health.
Longevity in Body	Short half-life, requires regular intake to maintain clotting factor levels.	Longer half-life, circulates longer in the bloodstream for wider tissue distribution.

Potential Benefits for Brain and Other Tissues

Research suggests vitamin K may also support brain function and have anti-inflammatory effects. Some studies link higher vitamin K levels to better cognitive performance in older adults. Its role in calcium regulation may also extend to other soft tissues. More research is needed in these areas.

How to Ensure Adequate Intake

A balanced diet typically provides enough vitamin K. Consuming it with some fat can aid absorption.

To increase your vitamin K intake, consider these steps:

Eat Your Greens: Include kale, spinach, broccoli, and collard greens for Vitamin K1.
Explore K2 Sources: Add fermented natto, certain cheeses, eggs, and organ meats for Vitamin K2.
Consider Supplements: Supplements may be needed for some individuals under medical supervision.
Include Healthy Fats: Eating greens with a source of fat, like olive oil dressing, can improve K absorption.

Conclusion: A Crucial but Often Overlooked Nutrient

Vitamin K's importance goes beyond blood clotting, encompassing significant benefits for bone and heart health, with potential roles in cognitive function and other processes. A diet rich in both K1 and K2 is the best way to gain these benefits. While deficiency is uncommon, consistent intake is important, particularly for those on certain medications or with absorption issues. Ongoing research continues to explore its full impact.

Get More Information on Vitamin K

For further details, consult the {Link: NIH Office of Dietary Supplements https://ods.od.nih.gov/factsheets/VitaminK-Consumer/}.

Frequently Asked Questions

The primary function is to activate proteins necessary for blood clotting, which is vital for healing wounds and preventing excessive bleeding.

Yes, vitamin K is essential for bone health as it activates proteins like osteocalcin, which helps bind calcium to build and maintain strong bones.

Yes, vitamin K, especially K2, helps prevent arterial calcification by activating Matrix Gla Protein (MGP), which inhibits mineral buildup in blood vessels.

Vitamin K1 is abundant in leafy green vegetables like kale, spinach, and broccoli. Vitamin K2 is found in fermented foods like natto, eggs, and certain meats and cheeses.

No, a clinical deficiency is rare in healthy adults. It is more common in newborns, or people with malabsorption issues or liver conditions.

Individuals taking blood-thinning medications like warfarin should be careful with their vitamin K intake, as it can interfere with the drug's effectiveness. Consult a doctor.

Yes, they have distinct functions. K1 primarily supports liver functions like blood clotting, while K2 is more involved in regulating calcium metabolism in bones and arteries.

There is no known toxicity associated with high oral doses of vitamin K1 or K2 from food or supplements, though it can interfere with certain medications like warfarin.