Vitamin K

What is Vitamin K? A fat-soluble vitamin essential for blood clotting, bone health and heart protection.

Two Forms:

• Vitamin K1:  found in leafy green vegetables
• Vitamin K2:  found in fermented foods and animal products

Too Little Vitamin K:

• Excessive bleeding or bruising
• Weak bones/osteoporosis
• Calcification of arteries

Groups at Risk of Deficiency:

• Chronic diseases (Chron’s, celiac, cystic fibrosis)
• Long term antibiotic or anticoagulant use
• Newborns (routinely given vitamin K at birth)

Too Much Vitamin K:

• No known toxicity from food sources
• People on blood thinners must keep vitamin K intake consistent, not avoid it

Just Right (adults):

• Recommended 90-120 micrograms/day

Medication Interactions

(consult your doctor)

• Blood thinners
• Antibiotics
• Cholesterol medications
• Orlistat (weight loss)

Food Sources

Animal – K2

• Aged Cheeses – especially gouda, brie and blue cheese
• Egg Yolks
• Chicken (dark meat)
• Liver (especially goose)

Plant based – K1

• Kale, Spinach, Collard Greens
• Broccoli, Brussels Sprouts
• Parsley, Basil
• Green beans, cabbage

• Natto (fermented soybeans) – highest known K2 source

Cooking tip:

Vitamin K is fat-soluble, so pair greens with healthy fats like olive oil, nuts or avocado to improve absorption.

Reference: Vitamin K – Health Professional Fact Sheet