Vitamin K may not be as famous as vitamin D, but it also has an important role to play in the prevention of osteoporosis. Vitamin K is a fat-soluble vitamin produced in the large intestine in humans, but also obtained from plant sources. The K in vitamin K stands for koagulationsvitamin, another clue as to the importance of vitamin K for its role in helping the blood to clot. While vitamin K can be taken in supplement form, it’s easy to obtain all the vitamin K you need from food sources. Vitamin K sources are abundant in the plant kingdom, and tasty, too.
Sources of Vitamin K
There are actually two forms of vitamin K: vitamin K1 and K2. Beef liver is one of the few meat-based sources of vitamin K. Green, leafy vegetables contain abundant amounts of vitamin K1, as does cruciferous vegetables. Eating plants containing large amounts of vitamin K1 helps you meet the RDA of 90 micrograms a day for men and women over age 19.
Good plant sources of vitamin K include:
• Kale (contains the highest amount of vitamin K) • Spinach • Collard Greens • Swiss Chard • Mustard and Turnip Greens • Broccoli • Brussels Sprouts • Cabbage • Asparagus
You don’t need much to meet the daily RDA for vitamin K. A half-cup of kale contains over 500 micrograms of vitamin K, which is five times the amount most adults need. Excess vitamin K can be store in the body for future use.
One thing to note about the food sources of vitamin K: freezing may decrease the amount of vitamin K in vegetables, but heating doesn’t seem to change it that much. So buying fresh kale and steaming it with some lemon juice or olive oil sprinkled on top may be a great way to get more vitamin K, but buying frozen kale or spinach may not enhance the amount of vitamin K you’re eating by all that much.
Why Worry About Vitamin K?
What if you hate vegetables, especially those dark green, leafy vegetables? Is it really that important to eat your veggies? The University of Maryland Medical Center’s website reports that new research links vitamin K with strong bones. In addition to calcium, vitamin K’s role in bone health may prevent osteoporosis, especially in postmenopausal women. Unless your doctor advises you against eating green, leafy vegetables, eating more may help keep bones healthy and strong.
Who Shouldn’t Take Extra Vitamin K?
It sounds odd that a doctor may advise against eating more spinach or chard, but in fact, some medications can and do interact with high amounts of vitamin K. Patients taking the blood thinner wafarin, for example, are advised not to eat high amounts of these vegetables because of vitamin K’s potential to interact with the medication. Whenever you take a medication, talk to your doctor about any considerations or cautions regarding food, diet and supplements. Read the pharmacy pamphlets and papers that come with your medications and consult with your doctor if you have any questions about your health, medications, or supplements.
Vitamin K Deficiency
Vitamin K deficiency is rare in countries with access to green, leafy vegetables year-round. The only people at serious risk for vitamin K deficiencies are those with damaged intestines, such as patients with Crohn’s disease. Those who take high doses of antibiotics may be at temporary risk for vitamin K deficiency, since antibiotics kill the good intestinal bacteria along with the intended victims, the bad bacteria in the body.
Vitamin K plays an important role in blood clotting, bone health, and overall good health. You can get plenty of vitamin K from food sources, but always check with your doctor about changing your dietary habits, especially if you are taking any medication or have a previously diagnosed medical condition. Vitamin K may not be as sexy as its cousins vitamin C and D, but it too plays an important role in your health and well-being. So steam up that kale, dice up those collars, and enjoy a cup of K today.
PHOTO CREDIT: Joy, joyosity, Flickr Creative Commons