Vitamin K (VK) is a term which includes a number of chemically related, fat-soluble compounds called as naphthoquinones
The group of vitamins include
Naturally occurring form of Vitamin K is Vitamin K1 which is found in plants. These plants become the primary source of Vitamin K in humans, after being consumed in the form of food.
The vitamin is required for synthesis of a protein which is vital for processes like:
Blood coagulation (clotting)
Bone metabolism (the protein helps to bind Calcium ions to bones and tissues)
Prevention of Vascular Mineralization
Other cellular functions
Vitamin K1, also called as phylloquinone, is largely found in green leafy vegetables as they are useful in the process of photosynthesis
Bacteria in the large intestine can convert K1 to Vitamin K2 (menaquinone)
Menaquinones are generally found in animal livers and fermented food
Another bacteria, Bacillus natto has been found to convert Vitamin K1 to K2 during the production of fermented soy products
Vitamins K3, K4 and K5 can also exist in synthetic form
Synthetic Forms of K3 (menadione) have been found to be toxic
VK storage capacity is very limited and so the body recycles it, by a process called as Vitamin K oxidation-reduction cycle
Certain drugs like warfarin, are known to obstruct Vitamin K absorption and metabolism
Where is Vitamin K2 produced in the body?
Vitamin K2 also known as menaquinone, is synthesized by the bacteria in the gastro-intestinal tracts. K2 is absorbed and sent to the blood vessel walls, bones and tissues excepting the liver.
Where is Vitamin K absorbed in the body?
Vitamin K, primarily in the form of phylloquinone, is absorbed in a form which is chemically unchanged after solubilisation. The absorption takes place in the proximal part of the intestine after bile salts and products of pancreatic lipolysis, form micelles with the soluble form of phylloquinone.
Where is Vitamin K stored in the body?
Vitamin K along with Vitamins A, D and E are fat-soluble vitamins. Therefore, they are most commonly stored in the fatty tissues of the human body.
How is Vitamin K beneficial to the body?
Vitamin K is important for bone health and healing of wounds
Blood coagulation is vital to stop bleeding, when the skin is punctured or cut
Vitamin K helps in producing 4 out of 13 proteins essential for blood clotting
The vitamin deficiency does not weaken the clotting mechanism of the body, mainly among adults
The deficiency may create problems in infants as Vitamin K cannot move through the placenta to the fetus effectively. It takes weeks to build up the stores of the vitamin.
Clotting Problems related to deficiency can be seen among people with severe gastro-intestinal or liver problems
Diets high in phylloquinone can be associated with lower risk of coronary artery disease, but this has not been conclusively proven till now
Vitamin K works along with Vitamin D to ensure that bones develop properly by helping proper transportation of calcium
Bone mineral density is positively affected by Vitamin K and reduces fracture risk Women with more of this vitamin in their diets, are less likely to fracture their hip
Vitamin K keeps demineralization of bones in check
A type of bone cell called as osteoclast is responsible for demineralization of bones
The osteoclasts take minerals from the bones and make them available for other bodily functions
A form of vitamin K2, the MK4, keeps the formation of osteoclasts under control
MK4 also initiates the programmed cell death by a process called as apoptosis
Carboxylation: Vitamin K increases the carboxylation of osteocalcin to keep the bones healthy.
Osteocalcin is a protein that needs to be changed by a process called carboxylation
When bones have fewer carboxylated osteocalcin, it is prone to fractures
Vitamin K is essential for the proper functioning of the carboxylase enzymes, that helps in carboxylation of the protein
The vitamin helps to restore the bone protein to its proper places and strengthens the composition of bones
The K2 form, particularly MK4, is helpful in post menopausal bone protection
Low levels of Vitamin K have been linked with increased risk of arthritis
Other health benefits that have been suggested but not scientifically proved, are:
Protection from cardiac disease
Decreased probability of Alzheimer's Disease
Reduction of risk of prostrate cancer
Why is Vitamin K important for the body?
Vitamin K is necessary when excessive blood thinning medicines are given, and the effect has to be reversed
New born babies have clotting problems, as the vitamin has not transferred from the mother's body to the infant
Treatment is essential for bleeding caused by certain medicines like:
Who discovered Vitamin K?
In 1929, a Danish scientist called as Henrik Dam first discovered Vitamin K1. He uncovered this by investigating the role of cholesterol in chickens, by providing them with only cholesterol-free food. After a certain amount of time, the chickens began hemorrhaging and bleeding.
What is the right amount of Vitamin K which is required by the body?
Vitamin K, like other supplements, should be taken under the strict supervision of a physician, especially before giving to a child. Some people have difficulty in absorbing nutrients like Vitamin K as they are suffering from conditions like:
Gallbladder or Liver disease
Celiac disease or Crohn's disease
People suffering from deficiency should take multi-vitamins instead of a Vitamin K-only supplement. Under special circumstances, doctors might give the patient a shot of Vitamin K.
The daily Adequate Intake is:
19 years and above
18 years and below
19 years and older
18 years and above
19 years and below
Can high intake of Vitamin K lead to toxicity?
Till date, there have been no reports of a toxic dose of Vitamin K unless supplements have been taken to specifically target Vitamin K activity
A satisfactory upper intake level (UL) has not been set for Vitamin K consumption
Research has shown that when Vitamin K is consumed at 500 times the Recommended Dietary Intake (RDI), no toxicity has been observed
People who enjoy large amounts of vegetables with their meals, may continue to do so without any hesitation
It must be reiterated however, that the risk of excessive Vitamin K intake may still apply to people taking supplements. Any form of self-medication should be avoided and pills should be taken after discussing with a physician.
What are the foods which are rich in Vitamin K?
The most common sources of phylloquinones are leafy green vegetables
Fresh green vegetables are also excellent sources of the vitamin
Some herbs and spices also supply good amounts of Vitamin K
Foods like kale are so rich in nutrients, they supply 10 times the Required Daily Intake
Besides fruits and vegetables, miso and soybean are vitamin K-rich food sources
Other providers of Vitamin K to the diet are:
Food items obtained from plants mostly contain Vitamin K1
Vitamin K2 is found in fermented plants and animal food. For example, miso, tempeh, etc.
Vitamin K is a fairly stable nutrient to common types of processing
The usual cooking procedures may lead to a slight decrease in the levels
During storage, Vitamin K amounts are found to be constant
Vitamin K in oils is more prone to decrease by the exposure to sunlight. That is why oils should always be stored in opaque bottles in dark places.
The hydrogenation process that is used to stabilize liquid fats, damages a notable amount of the Vitamin K content. That is one of the reasons hydrogenated oils should be avoided.
½ to 1/8 inches
How much Vitamin K does a cabbage contain?
Dark green leafy vegetables like cabbage contains high amounts of Vitamin K
Raw cabbage has 42 micrograms per cup of Vitamin K per cup
Cooking has been seen to triple the amount of the vitamin to about 162 micrograms
What is Vitamin K deficiency?
Low levels of Vitamin K lead to its deficiency which can further give way to profuse bleeding
Vitamin K deficiency is usually quite rare in adults, while more usual for new-born infants. A single shot of Vitamin K to infants is quite common.
Overdose of a blood thinner called Coumadin can also lead to Vitamin K deficiency
Deficiency due to phylloquinone (Vitamin K1) can lead to a condition called as Coagulopathy
The ailment causes difficulty in blood clotting
Prolonged or excessive bleeding can be caused after an injury or during medical or dental procedures
Menaquinone (K2) deficiency leads to
Coronary Heart Disease
Severe blood vessel calcification
What are the signs and symptoms of Vitamin K deficiency?
Vitamin K deficiency is usually quite rare as green leafy vegetables along with some green spices, contain an abundance of this nutrient
Bacteria in the intestines of our body actually produce this vitamin. But antibiotics should be avoided as much as possible as they are responsible for killing all the good bacteria in our gut.
Other Symptoms of Deficiency are:
Problems in Blood clotting or bleeding:
These may include:
Bleeding in the digestive tract
Bleeding of the gums
Heavy bleeding during menstruation
Calcification of the cartilage
Excessive bleeding during surgical procedures or in response to minor trauma
Internal bleeding in the skull of newly born infants. Also, formation of deformed fingers and underdeveloped facial structures can be the result of a Vitamin K deficiency.
Vitamin K helps in the all-round development of the fetus
It is necessary for a pregnant woman to be given Vitamin K food supplements
Lack of Vitamin K leads the body to go into emergency mode. Only critical functions are carried out for immediate survival. Meanwhile, other important processes are shut down leading to
Development of Cancer
Who are the people at risk of suffering from Vitamin K deficiency?
People with large amounts of coumarins, a known anti-coagulant, in their body
Synthesis of Vitamin K dependent elements is less for people suffering from liver diseases like:
Amyloidosis (accumulation of proteins in the form of insoluble fibers called as amyloid fibrils)
Gaucher's disease (a genetic disease which has abnormal metabolism and storage of fats)
Impaired absorption of nutrients by the digestive system, for people suffering from:
Short bowel syndrome due to various abdominal surgeries
Fat absorption is reduced in people afflicted with biliary tract diseases. So there is a decrease in fat soluble vitamins like Vitamin K in the body. This problem is faced by people with:
Common duct obstruction due to stones and strictures
Primary biliary cirrhosis
People suffering from deficiencies due to:
problems due to alcohol abuse
Patients receiving long-term parenteral nutrition without Vitamin K supplements
Interference in the absorption of Vitamin K1, decrease in the synthesis of Vitamin K2 in the intestine or degradation of Vitamin K, is seen in the case of some drugs such as:
What are the tests required to be performed to detect Vitamin K deficiency?
Vitamin K deficiency can lead to uncontrolled bleeding and bruising
Vitamin K Blood Test: Used to investigate bleeding and malabsorptive disorders
The most common test recommended by the doctor, is a combination of Prothrombin Time (PT) and Partial Thromboplastin Time (PTT) test which finds out the time required for the blood to form a clot
The PT and PTT Blood tests are useful for diagnosis for unexplained bleeding, especially when the person is not on blood thinning medication
Bleeding disorders include conditions like:
Heavy menstrual periods
Blood in the fecal matter (stool) and/or urine
The PT and PTT test is also ordered prior to a surgical procedure to ensure normal clotting ability
"Prolonged" result can indicate that the time taken for blood clot formation may be more than usual
A "Prolonged" outcome can signify a suspected Vitamin K deficiency
In that case, a Vitamin K supplement or pill may be prescribed
If the bleeding problem is resolved and the next diagnosis result is normal, then Vitamin K deficiency will be presumed to have been the cause
Vitamin K is rarely performed, as clotting malfunctions are investigated first with PT tests
Other Coagulation tests that can be performed are:
Platelet function Tests
Coagulation factor tests
Von Willebrand factor
What are the normal values for tests recommended for Vitamin K deficiency?
For impaired blood clotting: Vitamin K levels: Below 0.5 ng/mL
What is the price range for tests performed for Vitamin K deficiency?
The prices for tests for Vitamin K deficiency depend on various factors; such as, the type of hospital or diagnostic centre, the kind of test being performed or the city in which the test is being performed. To get a comprehensive list of the price range of diagnostic tests in your city, click HERE.
What are the treatment methods for Vitamin K deficiency?
The treatment for the deficiency depends on the seriousness of the bleeding and the conditions which may not be apparent at a glance
In adults, VK1 is given subcutaneously or intramuscularly
In case there is a risk for hematoma (a collection of clotted blood within the tissues) formation, an oral supplement of 5 to 20mg doses can be taken, after consulting a physician
VK3, a menadione, is a synthetic water soluble compound used to treat VK diseases due to faulty digestion or malabsorption of nutrients. Newborns are not treated with VK3 as it has been observed to give rise to hemolysis (rupture of red blood cells) at higher dosage.
Long term supplements may be needed for people suffering from chronic conditions
The treatment requires 2 to 5 days to display results
VK3 has been to known to show toxicity for large doses. Also, hemolytic anaemia has been seen in infants who have been given VK3.
Vitamin K supplementation may not be effective for people suffering from chronic liver disease
Vitamin K dependent factors which are essential to clotting, are produced in the liver
People having severely damaged livers may not be able to produce coagulation factors even with the availability of VK
How can Vitamin K deficiency be prevented?
A diet rich in Vitamin K. For example,
Green leafy vegetables
Oils like olive, cotton seed and soya beans
Green beans and peas
VK given to newly borns is very effective in preventing bleeding
For VK deficiency due to malabsorption conditions, Menadiol sodium phosphate is given. The synthetic compound is a water-soluble Vitamin K derivative that can be administered orally.
What is the prognosis of Vitamin K deficiency?
If the deficiency is detected early and treated appropriately, then the prognosis is good
Excessive bleeding due to VK deficiency can be fatal
What are the complications due to Vitamin K deficiency?
Complications due to VK are much rarer for adults, than new born babies
Infants have lower levels of VK than adults
Severe deficiency can cause Hemolytic Disease of the Newborn (HDN)
The disease is more usual in premature babies than those born full-term
Lower VK levels are attributed to:
Low levels of bacteria in new-born babies
Poor transportation of Vitamin K through the placenta to the fetus
Lesser amounts of VK in breast milk; so babies who are breastfed are prone to VK deficiency
Vitamin K shots are given to the infants right after birth, to protect them from HDN