Vitamin K
Vitamin K is a fat-soluble vitamin essential for blood clotting, bone metabolism, and cardiovascular health. It exists in two primary forms: vitamin K₁ (phylloquinone) and vitamin K₂ (menaquinone). While vitamin K₁ is primarily involved in blood clotting, vitamin K₂ has additional roles in bone and cardiovascular health. Adequate vitamin K levels are crucial for maintaining overall well-being.
Forms of Vitamin K
Vitamin K₁ (Phylloquinone):
Natural Form: Found in green leafy vegetables, such as spinach, kale, and broccoli.
Blood Clotting: Essential for the synthesis of clotting factors in the liver.
Vitamin K₂ (Menaquinone):
Bacterial Synthesis: Produced by bacteria in the human gut and found in fermented foods.
Bone Metabolism: Plays a role in bone mineralization and may contribute to cardiovascular health.
Functions of Vitamin K
Blood Clotting:
Clotting Factors: Vitamin K is necessary for the synthesis of proteins involved in blood clotting, such as prothrombin.
Bone Metabolism:
Osteocalcin: Vitamin K₂ is involved in the activation of osteocalcin, a protein important for bone mineralization.
Cardiovascular Health:
Arterial Calcification: Vitamin K may help prevent arterial calcification by regulating calcium in the arteries.
Cell Growth and Regulation:
Growth Arrest-Specific Protein 6 (Gas6): Vitamin K is involved in the activation of Gas6, a protein with roles in cell growth and regulation.
Sources of Vitamin K
Vitamin K₁:
Green Leafy Vegetables: Spinach, kale, broccoli, and Brussels sprouts.
Vegetable Oils: Soybean oil and canola oil.
Vitamin K₂:
Fermented Foods: Natto (fermented soybeans), cheese, and sauerkraut.
Animal Products: Meat and dairy products.
Recommended Daily Intake
Varied Recommendations: Recommendations for vitamin K intake vary by age, sex, and life stage. Adults generally require between 90 and 120 micrograms per day.
Deficiency and Risk Factors
Deficiency Symptoms
Easy Bruising: Due to impaired blood clotting.
Bleeding: Excessive bleeding, especially from wounds or mucous membranes.
Risk Factors
Fat Malabsorption: Conditions such as celiac disease, Crohn's disease, or bile duct obstruction can lead to vitamin K deficiency.
Antibiotic Use: Prolonged use of certain antibiotics may reduce vitamin K production by gut bacteria.
Interactions and Considerations
Medication Interactions
Anticoagulants: Vitamin K can interact with anticoagulant medications, affecting their effectiveness.
Vitamin K Shot: Newborns are often given a vitamin K shot at birth to prevent bleeding disorders.
