Vitamin K Foods
Eat properly, make sure you are getting all the required vitamins and minerals, have the correct number of portions of fruit and vegetables a day, don't forget to eat your share of super foods. Heard this advice before? It does not matter whether you are trying to eat a proper balanced healthy diet or embarking on a weight loss program, the advice comes pouring in. What about vitamin K, is it something we need to take a supplement or is enough provided by our normal diet?
Why Do We Need Vitamin K?
We need Vitamin K as it helps the blood to clot after a cut or injury. Most of the other vitamins our bodies require are supplied by our diet but vitamin k is different in that about half of the vitamin K we get is made for us by bacteria in the large intestine.
Importantly there are studies that point to it helping to maintain strong bones in the elderly.
Vitamin K Deficiency
Even though our bodies make vitamin K it is possible to suffer a vitamin k deficiency but it is rare, occurring usually when our body cannot properly absorb the vitamin from the intestinal tract.
Vitamin K plays an important role in our blood clotting and prolonged use of antibiotics can destroy gut bacteria, the deficiency can result in easy bruising and a prolonged bleeding time after an injury. Probiotic drinks and yoghurts that contain acidophilus bacteria help to boost levels of gut bacteria, ensuring we make enough vitamin K. If taking a course of antibiotics, it is a good idea to include products like these in your diet as some drugs can inhibit the absorption of this vitamin.
Interestingly babies are given an injection of vitamin K after birth as their gut is free of bacteria and breast milk does not contain much of this vitamin.
How Much Vitamin K Do We Need?
Vitamin K is a fat-soluble vitamin which means we do not need to have a top up every day. Any surplus of the vitamin our body does not require to use right away is stored in the liver for future use.
We should be able to get all the vitamin K we need by eating a varied and balanced diet.
A safe intake is considered to be 1mcg per kilogram of body weight. For example, a person who weighs 70kg will need about 70mcg of vitamin K each day
Should you decide to take vitamin K supplements it is a good idea not to take too much as this might be harmful. The advice given is that taking 1 mg or less of vitamin K supplements a day is unlikely to cause any harm.
Please be aware that if you take warfarin (a blood thinner), you should know that vitamin K or foods containing vitamin K can affect how the drug works. It is very important that you ask your general practitioner or health carer the amount of vitamin K or vitamin K-containing foods you should consume.
The vitamin has been reified. A chemical intangible originally defined as a unit of nutritive value, it was long ago reified into a pill. Now it is a pill; no one except a few precise scientists define it as anything else. Once the vitamin became a pill, it became "real" according to the precepts of American Cartesianism: "I swallow it, therefore it is." Florence E. King (1936-, American author, critic)
Vitamin K Food Sources
Vitamin K is found in green leafy vegetables such as broccoli, cabbage, cauliflower and spinach. It is also present in vegetable oils and cereals. Small amounts can also be found in meat such as pork and dairy foods such as cheese.
An example of foods high in vitamin k:
- Asparagus
- Broccoli
- Brussels sprouts
- Cabbage
- Cauliflower
- Endive
- Kale
- Leek
- Lettuce
- Olive oil
- Parsley
- Peas
- Soybean oil
- Spinach
- Swiss Chard
- Watercress
Vitamin K and bone health
A postscript to this article for those who seek more in depth knowledge about Vitamin K and bone health is printed courtesy of The National Library of Medicine.
In the past decade it has become evident that vitamin K has a significant role to play in human health that is beyond its well-established function in blood clotting.
There is a consistent line of evidence in human epidemiologic and intervention studies that clearly demonstrates that vitamin K can improve bone health.
The human intervention studies have demonstrated that vitamin K can not only increase bone mineral density in osteoporotic people but also actually reduce fracture rates.
Further, there is evidence in human intervention studies that vitamins K and D, a classic in bone metabolism, works synergistically on bone density. Most of these studies employed vitamin K at rather high doses, a fact that has been criticized as a shortcoming of these studies.
However, there is emerging evidence in human intervention studies that vitamin K at a much lower dose may also benefit bone health, in particular when co administered with vitamin D. Several mechanisms are suggested by which vitamin K can modulate bone metabolism.
Besides the gamma-carboxylation of osteocalcin, a protein believed to be involved in bone mineralization, there is increasing evidence that vitamin K also positively affects calcium balance, a key mineral in bone metabolism.
The Institute of Medicine recently has increased the dietary reference intakes of vitamin K to 90 microg/d for females and 120 microg/d for males, which is an increase of approximately 50% from previous recommendations. (Vitamins and Fine Chemicals Division, Human Nutrition & Health, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland).
