Foods High In Vitamin K
Vitamin K helps to put calcium where it belongs... in the bones and teeth... and keep it away from the places it doesn't belong such as our arteries. The foods high in vitamin K include most dark leafy green vegetables.
The United States Department of Agriculture (USDA) Food and Nutrition Center provides us with an excellent list of foods high in vitamin K that will help us to build a diet that is great for the prevention of osteoporosis. A cup of dark leafy greens can provide more than the recommended daily requirement of 90-120 mcg a day and will also provide the 200 micrograms that some research suggests is necessary for optimal bone health. The following lists shows the amount of vitamin K1 in one cup of cooked vegetables:
- Kale: 1062 mcg
- Spinach: 888 mcg
- Collards: 836 mcg
- Beet Greens: 697 mcg
- Swiss Chard: 573 mcg
- Broccoli: 220 mcg
- Brussel Sprouts: 218 mcg
- Cabbage: 163 mcg
Chinese cabbage (also known as pak-choi, bok choy or Korean kim chi) contains only 57.8 mcg in a cup of vegetables but when combined with tofu it provides an outstanding balance of calcium, magnesium and vitamin K for a very bone healthy meal.
It is important to note that spinach, swiss chard and beet greens have a high content of oxalates which tend to bind calcium and prevent its absorption. This does not mean that they should be avoided as they are excellent sources of vitamin K but it may be better to take a calcium supplement when these leafy greens are not part of your meal.
Despite my good intentions, I don't always eat all the dark leafy greens that are needed for healthy bones. So I take vitamin K2 supplements in the form of MK-7 (derived from fermented soy or natto) which costs approximately 25 cents for a softgel tablet or $95 for a year’s supply.
While lettuce provides some vitamin K, it cannot be described as rich in vitamin K like a dark leafy green. The USDA reports that one cup (56g) of lettuce provides the following amounts of this important vitamin:
- Green Leaf: 97 mcg
- Romaine: 57 mcg
- Iceberg: 13 mcg
Interestingly, Kellogg's Special K is very low in vitamin K. The USDA reports that one cup of the cereal has only .2 mcg of vitamin K.
Some research suggests that K2 (MK-4 through 10) from eggs and meats are better at facilitating calcium absorption than K1 from vegetables. Vitamin K2 is highest in products from animals that have been fed on fast growing grasses and may be found in the butter, non-skim milk, cheese, organ meats and fat of these animals.
If you are taking a blood thinning medication or an anticoagulant (such as Warfarin,Coumadin or Heparin) be sure to consult your doctor before increasing vitamin K in your diet or supplements.