Vitamin K deficiency is rare in healthy adults. The reason is simple, we do not need much of the vitamin, and we get enough healthy dose by consuming balanced and healthy diet.
Even those that eat burgers, can get some vitamin K thanks to lettuce and other veggies.
With that in mind, the deficiency mostly happens in infants https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3773869/. Adults can get deficient in vitamin K, but that is rarity.
The main symptom is excessive bleeding, as vitamin K is responsible for forming blood clots.
Let’s take a look at the function of vitamin K, how it helps our body, what are the causes of deficiency, symptoms, and what you can do about it.
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What is vitamin K?
The vitamin comes in two forms, K1, and K2. The former is found in plant foods like leafy green vegetables, while the latter is produced in our gut and intestines.
The medical term for K1 is phylloquinone, while the term for K2 is menaquinone. Vitamin K2 is found in the body and created natural in the intestinal tract, but also sourced from fermented foods.
Both vitamin K types are essential for our health, as they are responsible for producing a protein that helps the blood to clot. As we know, blood clotting and coagulation prevents excessive bleeding, both internally and externally.
Our body cannot produce enough vitamin K on its own, so we need to source it from some vitamin K foods, every now and then.
Most healthy adults get enough, and even more of the recommended daily intake by the food they eat and produced naturally in the body.
However, some medications and conditions can inhibit absorption of the vitamin, leading to deficiency in the vitamin.
Causes and risk factors for deficiency
As mentioned previously, healthy adults usually do not experience deficiency of vitamin K. However, certain conditions and risk factors can lead to developing symptoms.
Here are some of risk factors.
- People taking anticoagulants that prevent blood clots and also inhibit vitamin K absorption and activation
- Patients taking antibiotics that interfere with the way our body produces and absorbs vitamin K
- People that consume extremely high doses of vitamin A or E
- People that do not consume enough foods high in vitamin K
- Patients with celiac disease, cystic fibrosis, intestinal or biliary tract disorder, or those who have had part of their intestine removed, as they have troubles absorbing the vitamin
- Patients who have a condition that prevents the body from absorbing fat properly, a condition otherwise known as fat malabsorption https://www.ncbi.nlm.nih.gov/pubmed/17923470
Newborn babies are more prone to deficiency, and there are a number of reasons for that.
- Drinking breast milk that is low in vitamin K
- The liver of the newborn is unable to use the vitamin K efficiently
- Vitamin K does not transfer well from a mother’s placenta to her baby
- The gut of the newborn cannot produce vitamin K2 in the first few days of his/hers life
How much vitamin K you need?
According to the nutrition and dietician experts, healthy adult males need 120 micrograms of vitamin K, while healthy female adults need 90mcg of the vitamin per day https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/.
You can easily source that from vitamin K foods.
Symptoms of vitamin K deficiency
As mentioned previously, the most common symptom of deficiency in vitamin K is excessive bleeding https://www.ncbi.nlm.nih.gov/pubmed/24300958.
But that is just one of the symptoms. There are many more symptoms that are related to the vitamin and its deficiency.
The problem with excessive bleeding is that the symptom might not be visible and evident immediately. You have to be cut or wounded and bleed in order to notice the symptom.
That is why you need to pay attention to other symptoms as well.
- Bruising easily
- Stool that is dark black
- Stool and urine contain blood
- Small blood clots forming under the nails
- Bleeds in mucous membranes that line areas inside the body
If physicians are looking for signs and symptoms of deficiency in vitamin K in babies and infants, they will also look for:
- Sudden brain bleeds, deemed severe and potentially life-threatening
- Bleeding in the skin and nose
- Bleeding in the gastrointestinal tract
- Bleeding at the penis if the baby has been circumcised
- Bleeding from the area where the umbilical cord has been removed
How to diagnose?
When you notice symptoms of vitamin K, you should speak with your physician. The doctor will ask about your medical history to check for risk factors.
The standard test for diagnosing deficiency is a coagulation test called the “prothrombin time or PT test”.
To perform the test, a medical care person will draw blood using a small needle. Chemicals are then added to the blood and observed in the laboratory to see how long it takes to clot.
Blood from a healthy person clots in less than 13.5 seconds. If it takes longer than that, a doctor may suspect in deficiency in vitamin K.
Before taking a test, certain foods should not be consumed, including kale, green tea, soybeans, cauliflower, broccoli, and liver products.
Vitamin K and newborns
As mentioned previously, newborns and infants are at higher risk of developing deficiency in vitamin K https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3021393/.
Therefore, it is now almost mandatory that a vitamin K injection is administered at birth to prevent the deficiency occurring in newborn babies.
The American Academy of Pediatrics recommends a single shot of 0.5 to 1mcg of vitamin K at birth. Risk factors for babies developing deficiency in the vitamin include:
- Babies that are born prematurely
- Newborns not given vitamin K at birth
- Newborns that are breast-fed exclusively and exposed to antibiotics
- Babies who have fat malabsorption due to gastrointestinal or liver disease
- Babies with mothers taking anti-seizure drugs, anticoagulants, or drugs for tuberculosis
Parents are the ones deciding whether their baby will receive a vitamin K or not. While it is recommended, it is not mandatory.
What is the treatment for deficiency?
The standard treatment for deficiency is a drug called phytonadione https://en.wikipedia.org/wiki/Phytomenadione.
This is basically a drug containing vitamin K1, and in most cases, doctors prescribe it as an oral medication.
In some severe cases, a doctor or a nurse can inject it under the skin, as opposed to into a vein or muscle. The dosage can range between 1 to 25mg for adults.
Healthy adults taking anticoagulants will take smaller dose in order to avoid complication. Anticoagulants interfere with the body’s ability to produce and absorb vitamin K.
Can you prevent deficiency?
While there is no set amount of vitamin K you should consume through vitamin K rich foods, there is a recommended dose https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4862383/.
As mentioned previously, it is 160mcg for men and 90mcg for women. You can prevent deficiency in the vitamin by consuming enough foods high in vitamin K.
Here is a quick list of some foods to include in your diet:
- Kale – 531mcg per cup, cooked
- Mustard greens – 415mcg per cup, cooked
- Swiss chard – 398mcg in one leaf
- Collard greens, 396mcg per half a cup, cooked
- Natto – 313mcg in one ounce
- Spinach – 145mcg in 1 ounce, raw
- Broccoli – 110mcg per half a cup, cooked
- Brussels sprouts – 109mcg per half a cup, cooked
- Beef liver – 72mcg per slice, cooked
- Pork chops – 59mcg per 3 ounces, cooked
- Chicken – 51mcg per 3 ounces
- Green beans – 30mcg in half a cup, cooked
- Prunes – 28mcg per 5 pieces
- Hard cheeses – 25mcg per 1 ounce
- Soft cheeses – 17mcg per 1 ounce
- Avocado – 21mcg in half a medium avocado
What are benefits of vitamin K?
While vitamin K is not as essential to our health as vitamin C, it still plays a role in a number of functions in our body.
Here are some of the benefits you reap by consuming enough of the vitamin:
- Prevent and treat cancer
- Improve bone health
- Help with blood clotting
- Promote heart health
- Boost brain function
- Improve insulin sensitivity
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