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Nutritional Sources of Vitamin K and Why We Need It

Danish scientist Henrik Dam discovered Vitamin K through an experiment in which he fed chickens a diet extremely low in cholesterol. In a few weeks, the animals began to bleed.

Danish scientist Henrik Dam discovered Vitamin K through an experiment in which he fed chickens a diet extremely low in cholesterol. In a few weeks, the animals began to bleed.

What Is Vitamin K?

After vitamins A,B,C,D and E comes Vitamin K. It was first discovered by Henrik Dam in a rather unpleasant experiment whereupon he fed chickens a diet that was extremely low in cholesterol. After a few weeks the animals showed signs of haemorrhage and started bleeding. Dam attempted to reverse this effect by feeding the chickens purified cholesterol but this did not work, so he came to the conclusion that he must have also been removing another compound from the chickens diet by accident whilst removing the cholesterol. He went on to name this compound the "coagulation vitamin."

Dam’s discovery was first published in a scientific journal based in Germany which named the compound Koagulationsvitamin. Hence it became vitamin K from the first letter of its name.

The vitamin K group of vitamins are vital for the synthesis of proteins that are required for blood coagulation (or clotting) needed by the body for controlling binding of calcium in bones and other tissues. Without vitamin k these proteins are unable to bind to calcium ions.

In humans with a vitamin K deficiency, blood coagulation, or clotting, is hindered and uncontrollable bleeding can occur. Vitamin K helps strengthen bones and prevents calcification of the arteries and other soft tissues.

Vitamin K is produced in the highest quantities in green leafy vegetables, so let’s take a look at exactly what foods we can include in a regular diet to obtain the most health benefit from this essential vitamin.


7 Foods Rich in Vitamin K, the "Coagulation Vitamin"

FoodHow to Get Recommended 120 micrograms

1. Kale

2. Collard Greens

One cup, boiled, give 770 micrograms, so eating this once a week is sufficient.

3. Spinach


4. Turnip Greens

One cup contains 588% of recommended Vit. K, so weekly consumption is sufficient.

5. Brussels Sprouts

One cooked cup offers 300 micrograms of Vit. K

6. Broccoli

One steamed cup is twice daily reccommended Vit. K

7. Spring, or Green Onions

Foods That Contain Vitamin K

  • Kale – Easy to remember as it also starts with the letter ‘K’ not only is kale packed full of vitamin K but it is also a store house of many other compounds that can be of huge benefit for our bodies. Kale has been shown to play a role in regulating our blood sugar levels, hence it is of great benefit for the diets of those suffering with diabetes. It has also been shown to be effective in helping to reduce blood pressure, lower the risk of cancer and heart disease. Kale can help maintain healthy skin, hair and bones and aids digestion.
  • Collard Greens – The daily recommended allowance of vitamin K is 120 micrograms for men and 90 micrograms for women. One single cup of boiled collard greens will give you 770 micrograms, so you aren’t going to need to eat them too often to keep your vitamin k levels topped up to the max. Collard greens have also been shown to be effective in lowering the risk of contracting many forms of cancers including lung cancer, prostate cancer, melanoma, pancreatic and esophageal cancer. Collard greens have been shown to help regulate sleep and moods and could be helpful for sufferers of depression. They contribute towards healthy hair, skin and bones, aid digestion and can also be of benefit to sufferers of type 1 and type 2 diabetes.
  • Spinach – Rich in vitamin K, spinach is also a great and tasty source of vitamins A, C, B2, B6, E, magnesium, manganese, copper, potassium, iron, phosphorus and calcium. With a list of nutrients and compounds like that, including spinach in your diet regularly will bring a whole host of health benefits such as lower blood pressure, a healthy heart and it also aids with mental function including improving memory recall and concentration.
  • Turnip Greens – Somewhat of an acquired taste, turnip greens vitamin K punch comes in at a whopping 588% of your recommended daily allowance per cup. Along with vitamin K, one cup will also give you 61% of your daily vitamin A. As with the other vitamin K rich food sources we have explored so far, regular consumption of turnip greens has been found to play a role in significantly lowering the risk of a number of cancers including bladder cancer, breast cancer, colon cancer, lung cancer, prostate cancer, and ovarian cancer.
  • Brussels Sprouts – Brussels may not be everyone’s favourite green leafy veg but they pack a hefty punch where nutrients and vitamins are concerned. One cup of Brussels sprouts, cooked from frozen will give you 300 micrograms of vitamin K and if you steam them they will also give you a boost if you are trying to lower your ldl cholesterol readings. Whilst one cup of Brussels will easily give you twice your recommended daily intake of vitamin K, they will also give you more than 100% of your daily vitamin C too. Brussels contain a range of B vitamins, essential for keeping our energy levels optimized and are also a good source of omega-3 fats which also help with maintaining a healthy heart and even giving you a mood boost if you are feeling depressed!
  • Broccoli – Once again, one cup of steamed broccoli will give you at least twice your daily amount of vitamin K. As with Brussels sprouts, broccoli has ldl cholesterol lowering properties, so if you are seeking to keep your heart healthy it should be an essential element in your diet. Sufferers of hay fever and other allergies should also take note that broccoli contains a flavonoid named kaempferol which has been demonstrated to lessen the effects of allergy related substances on our body.
  • Spring Onions – Packed full of vitamin K, spring onions will also deliver your body a good amount of vitamins A and C. Spring onions can also help lower blood sugar levels, so they are an essential food for individuals suffering from diabetes. Spring onions have been and continue to be used as a medicine to relieve the symptoms of the common cold and flu and are also of benefit to the blood circulatory system.

Check With Your Doctor Before Using Supplements

As the foods we have listed are packed full not just of vitamin K but also a whole host of other vitamins and nutrients that are essential for good health and optimal functioning, everyone should be including some of these foods into our diet on a daily basis. For many people though, some of the tastes and smells of these green leafy veg can be bitter and pungent. For those people it is of the highest importance to make sure they are getting enough vitamin K through other sources. There is a wide array of foods containing vitamin K but if you are not getting enough vitamin K, supplements are a good option. Keep in mind that if you are using other medications or are pregnant, you should check with your health practitioner before you add any supplements to your diet.

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

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