What is it? Vitamin K takes its name from the Danish word koagulation, which means blood-clotting. It is a fat-soluble vitamin, meaning our bodies store it away in our fatty tissue.

Why do we need it? The body relies on vitamin K to build the proteins necessary for blood to properly clot. Vitamin K may also play a role in bone health.

How much do we need? Babies require very little vitamin K, though newborns often receive a shot of the vitamin soon after birth. For infants up to the age of one year of age, 2 to 2.5 micrograms (µg) each day is enough. After that, daily needs increase sharply:

  • 1 to 3 years of age: 30 µg
  • 4 to 8 years of age: 55 µg
  • 9 to 13 years of age: 60 µg
  • 14 to 18 years of age: 75 µg
  • 19 and older: 90 µg for females and 120 µg for males

Talk to your doctor if you take blood thinners, since vitamin K affects clotting.

Where is it found?

Some of the body's vitamin K is created by bacteria in the intestines, but we get much of it from the foods we eat.

Vegetables and fruits

  • asparagus
  • avocado
  • bell pepper
  • broccoli
  • cranberries
  • fresh parsley
  • kale
  • mustard greens
  • spinach
  • swiss chard
  • tomato

Nuts, seeds, and legumes

  • kidney beans
  • miso
  • pumpkin seeds
  • soybeans

Other sources

  • green tea
  • 2% cow's milk

Amy Toffelmire