Vitamin K - where it occurs, what it helps, deficiency symptoms

Vitamin K is involved in blood clotting and regulates the body's calcium balance. The daily requirement of vitamin K is covered by intestinal flora bacteria and a diet rich in green vegetables.

AuthorNina Wawryszuk

Natu.Care Editor

Nina Wawryszuk specialises in sports supplementation, strength training and psychosomatics. On a daily basis, in addition to writing articles for Natu.Care, as a personal trainer she helps athletes improve their performance through training, diet and supplementation.

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Reviewed byWitold Tomaszewski

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Reviewed byWitold Tomaszewski

Doctor of Medicine

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Fact-checkingAgata Jach

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Vitamin K - where it occurs, what it helps, deficiency symptoms

29 April, 2024

15 min

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Did you know the role that ... chickens played in the discovery of vitamin K? Many of them sacrificed their health so that today we understand what vitamin K is and how important it is for our bodies.

In this article, I will introduce you to the somewhat surprising history of the discovery of vitamin K and, together with Dr. Witold Tomaszewski, M.D., I will introduce you to the functions, best sources and symptoms of deficiency of this vitamin. After reading the article, you will become better acquainted with the "coagulation vitamin" and develop a taste for... salad.

Description of contents:

The curious circumstances of the discovery of vitamin K
Vitamin K properties
What vitamin K helps
Where is vitamin K found? Best sources
Vitamin K deficiency - symptoms
Effects of vitamin K deficiency
Vitamin K excess - is it possible
Daily requirement of vitamin K
Contraindications and precautions
Summary

See also:

Interesting circumstances of the discovery of vitamin K

In 1929, Danish scientist Henrik Dam studied and the process of cholesterol metabolism in the body by feeding chickens a fat-free diet. After a few weeks, the animals began to suffer from bleeding in the subcutaneous tissue, muscles or organs.

Adding cholesterol to the diet did not help, so Dam postulated that - in addition to fat - there must be another compound in the diet to prevent bleeding. Haemorrhages in chickens regressed when alfalfa, spinach or cabbage were included in the diet (they have a high vitamin K content).

Following further research, he found a factor in hemp seeds that prevented bleeding and decided to call it the clotting vitamin. In German, it was labelled "coagulation vitamin" (coagulation) and so the new vitamin was given the letter K.

The new vitamin was named vitamin K.

Vitamin K - properties

It is one of the 4 vitamins fat-solubleand, along with the vitamins A, D and E. Vitamin K is actually a group of 3 organic chemical compoundsand.

In this group are:

Vitamin K1 (phylloquinone)

It is synthesised by plants - found in green leafy vegetablesand. It is the main source of vitamin K in the diet of Europeansand.

Vitamin K2 (menaquinone)

It is mainly found in meat, cheese and eggs. It is also produced by the bacteria that make up our intestinal flora of the digestive system. The synthesis of this vitamin by the microorganisms found in the jejunum and ileum, covers a significant part of the daily requirement for vitamin K.

Vitamin K3 (menadione)

Synthetic form of vitamin K, acting as a provitamin (a chemical compound that is converted into a vitamin in the body under the influence of enzymes or sunlight). It is used as a haemostatic drug.

What does vitamin K help with?

Vitamin K affects several important processes in our body.

Helps the cardiovascular system by strengthening blood vessel wallsand.
Participates in the formation of proteins needed for proper clotting of blood.
Along with osteocalcin, has effects on the production of healthy bone tissue .
Helps the calcification of bone tissue by the skeletal system, participating in the formation of bone tissue .
Strengthens the immune system .

Scientists are also looking at the likely properties of vitamin Kand. The work is ongoing, and the researchers are particularly interested in the role of vitamin K:

as a protective factor in the development of liver cancer and in reducing the risk of death in patients with cirrhosis and cancers originating from hepatocytes (the cells that make up the liver),
in its ability to increase the sensitivity of target tissues to insulin,
in reducing the risk of the onset and development of coronary heart disease.

Good for immunity

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Omega-3 content: 250 mg (200 mg DHA + 50 mg EPA)
Additional active ingredients: vitamin D3, vitamin K
Form: capsules
Dose: 1 capsule per day
Sufficient for: 30 days

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Product description

A dietary supplement containing omega-3 fatty acids, vitamin D3 and vitamin K. The formula supports the immune system, the functioning of the mós brain and vision. Moreover, its regular supplementation has a positive effect on teeth, as well as the use of calcium in the body, whichóry supports the musculoskeletal system. A daily portion provides 2000 IU of vitamin D3, which covers the requirement for an adult. Vitamin D3 supplementation is particularly recommendedólly during autumn and winter.

Pros and cons

Additional information

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Pure composition

Primabiotic Vitamin D3+K2Mk7

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Content vitamin D3: 2000 IU
Additional active ingredients: vitamin K
Form: drops
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Product description

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Pros and cons

Additional information

Where is vitamin K found? Best sources

Daily vitamin and mineral requirements are best met with a balanced and varied diet. Find out where you can find the most vitamin K - compose a meal that is tasty and rich in this vitamin.

Productsand rich in vitamin K1 (values given per 100 g):

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Product	Content
dried basil	1714.5 µg
dried sage	1714.5 µg	1714.5 µg
dried thyme	1714.5 µg	1714.5 µg
fresh parsley	1640 µg
dried coriander leaf	1359.5 µg
raw chard	830 µg
raw dandelion	778.4 µg
cooked Chinese cabbage	623.2µg
dried marjoram	621.7µg
dried oregano	621.7 µg	621.7 µg
cooked mustard	592.7 µg
raw cress	541.9 µg
cooked spinach	540.7 µg
cooked turnip	518.9 µg
cooked beetroot	484 µg
cooked kale	418.5 µg
chives	212.7 µg
cooked Brussels sprouts	193.5 µg
soybean oil	183.9 µg
mayonnaise	163 µg
broccoli	141.1 µg
green lettuce	126.3 µg
cooked cabbage	108.7 µg
raw arugula	108.6 µg
margarine	101.3 µg

It is worth adding spices to your dishes not only to enhance their flavour and aroma - they are also real vitamin K bombs.

Best sources of vitamin K2and (values quoted per 100 g):

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Product	Value
natto (a Japanese dish made from fermented soybeans)	998 µg
soft cheeses (e.g. mozzarella, feta)	506 µg
mould cheese	440 µg
goose liver	369 µg
hard cheeses (e.g. gouda, edam)	hard cheese	282 µg
beef liver	106 µg
hen's egg yolk	67-192 µg
carb	63 µg
pepperoni	41.7 µg
whole milk	38.1 µg
turkey sausage	36.6 µg	36.6 µg
chicken meat	35.7 µg
bacon	35 µg
frankfurter turkey	31.2 µg
salami	28 µg

From the whole combination, you can compose a very tasty and valuable salad rich in vitamin K1 and K2. Do you have an idea? Leave it to me in a comment below the article, I'd be happy to try it.

Vitamin K deficiency - symptoms

Vitamin K deficiency is rare in adult individualsand. The daily requirement is largely covered by the synthesis of vitamin K2 by the intestinal microflora, and the rest is supplemented by vitamin K1 supplied with food.

Deficiency usually results from disorders in the process digestion or absorptionand in the gastrointestinal tract and in adults may manifest as:

prolonged wound healing time,
haemorrhages,
easy formation of bruises,
disorders of the bowel,
frequent diarrhoea,
frequent diarrhoea,
reduced immune function,
diarrhoea.
lower immune function,
heavy menstrual periods
abundant menstruation in women,

Infants are at risk of vitamin K deficiency due to incompletely formed intestinal flora and low vitamin K content in breast milk.

Nevertheless, infants are at risk of vitamin K deficiency.

Vitamin K2 deficiency in infants can be manifested by:and

bleeding from the site where the umbilical cord was removed,
.
bleeding in the skin, nose, gastrointestinal tract or elsewhere,

bloods from the skin, nose, gastrointestinal tract or other areas.
bleeding from the penis (if the child has been circumcised),
.
increased bleeding into the brain,
.

The Polish Neonatal Society recommends vitamin K supplementation for infantsand. All newborns should receive vitamin K (usually by injection) within the first 5 hours of life.
.
Effects of vitamin K deficiency
.
Unmedicated vitamin K deficiency can lead to:

disorders of blood clottingand,
.
increased risk of cardiovascular disease ,

osteoporosis ,

vascular calcification (calcification),

haemorrhages ,
.
hepatitis ,
.

Remember - vitamin K deficiency is rare. It's good to be aware of the symptoms of deficiency, but if you take care of a varied diet and don't have problems with your digestive function - don't worry about a deficiency of this vitamin.

Vitamin K excess - is it possible?
.
Vitamin K overdose occurs rarelyand. Symptoms of overdose reported in the literature include: feeling hot, excessive sweating, breakdown of red blood cells and symptoms of haemolytic anaemia.

The toxicity of vitamin K usually involves menadione, a synthetic vitamin K3and.

.
Despite the fact that no toxic dose has been reported in the scientific literature, patients should not take excessive amounts of vitamin K. Instead, they should be encouraged to eat a healthy, balanced diet with green leafy vegetables rather than supplementing with this vitamin.
.
.
Dr. n. med. Witold Tomaszewski
.
.

Daily vitamin K requirements
.
Because of insufficient evidence regarding the function, absorption and occurrence of menaquinones (vitamin K2) in humans, standards have been set only for phylloquinone (vitamin K1).

Standards for vitamin Kand for Poland, set at adequate intake (AI)*
.

Group, gender, age
.
µg vitamin K (phylloquinone)/person/day
.

Infants
.
0-6 months

7-11 months

5

8.5

Children

1-3 years

4-6 years

7-9 years

15

20

25

Boys

10-12 years

13-15 years

16-18 years

40

50

65

Girls

10-12 years

13-15 years

16-18 years

40

50

55

Males >19 years

55

Women, pregnant and breastfeeding women >19 years

55

*AI (Adequate Intake) is a dietary recommendation used when there is insufficient data to calculate average intakeand.

See also articles on health:
.

Blood tests [how often to do them + how to prepare]
.
Cortisol testing [standards + price]
.
Thyroid tests [which ones to perform + norms + results]

.
In 2020. The Dietary Supplements Panel of the Sanitary and Epidemiological Council has set the maximum amount of vitamin K in a daily recommended serving of a dietary supplement for adults at 200 µg.

.
Dr. n. med. Witold Tomaszewski
.
.

Contraindications and precautions
.
The use of vitamin K requires precautionsand u:

newborns,
.
patients with renal impairment,
.
patients with hereditary hypoprothrombinemia (prothrombin - blood clotting factor deficiency),
.
patients with excessive anticoagulation,
.
patients with hypersensitivity to vitamin K,
.

Pregnant and breastfeeding women should consult a physician before supplementation.

See also other articles on vitamins and minerals:
.

Vitamin B12 deficiency [causes + symptoms + treatment]
.
Vitamin D deficiency [symptoms + treatment]
.
Potassium [deficiency + norm + what it's in]

Zinc [properties + deficiency + excess]
.
Iron [properties + sources + deficiency]

Selenium [properties + dosage + supplementation]
.
Iodine [properties + dosage + deficiency symptoms]
.

Do you know any other interesting facts about vitamin K? Share them in the comments. I'd love to read about them while I'm eating my greens.

Summary
.
.
From this article, remember (and surprise your friends with how vitamin K was discovered!):

Vitamin K is made up of three compounds: K1 (phylloquinone), K2 (menaquinone) and K3 (menadione).

Vitamin K is fat-soluble.
.
Daily requirements are met through the bacteria of the intestinal flora of the digestive system and from a diet rich in green vegetables.

Vitamin K supports the cardiovascular and skeletal systems and plays an important role in the blood clotting process.

Vitamin K deficiency and excess are rare.
.

FAQ
.
.
What does vitamin K do?
.
Vitamin K is a group of compounds (including vitamin K2) that is essential for normal blood clotting, as well as bone health and cardiovascular function.

Vitamin K is responsible for, among other things:

blood clotting processes - vitamin K deficiency leads to disorders and increases the risk of bleeding;
.
regulation of bone mineralisation - activates proteins that bind calcium in bones;
.
heart health - affects the ability to break down fats in the body;
.

.
Where is vitamin K found and what is it most abundant in?
.
Vitamin K naturally occurs mainly in two forms - K1 and K2. Vitamin K1 is synthesised by plants, while K2 is synthesised by the bacteria Bacillus subtilis natto, which participates in natural fermentation processes.

Vitamin K can be found in products such as:

green leafy vegetables - e.g. spinach, kale, broccoli, lettuce, cabbage, parsley;

fruits - e.g. spinach, kale, broccoli, lettuce, cabbage, parsley
fruits - e.g. avocados, kiwi, grapes, strawberries, blueberries;
.
meat - e.g. turkey, goose liver, chicken, beef liver;
.
nobody - e.g. cheeses (soft, hard, mouldy), whole milk;
.
fermented products - e.g. kefir, yoghurt, kimchi, tempeh;
.

.
From when to give vitamin K to newborns and infants?
.
Vitamin K does not pass easily through the mother's placenta, so babies are born with low levels of vitamin K in their blood. Furthermore, the intestinal bacteria that synthesise it are not yet fully developed. It is therefore advisable to give vitamin K in the first hours after birth - either by injection, orally or by intravenous infusion. Subsequent doses should be given according to the doctor's recommendations during the first few months of life - there is not enough vitamin K in breast milk.

.
What are the symptoms of vitamin K deficiency?
.
The most important symptoms and effects of vitamin K deficiency are:
.

disorders of blood clotting;

a reduced risk of bleeding.
increased risk of bleeding;
.
weakening of muscles;
.
decreased bone density;

increased risk of bleeding;

increased risk of bleeding
impaired functioning of the liver;
.
increased risk of cardiovascular disease;
.

If you observe any symptoms, be sure to consult your doctor, who will order detailed diagnostic tests and order appropriate treatment.

.
How to supplement vitamin K?
.
The most common ways to supplement vitamin K deficiency are:
.

a balanced diet - include green leafy vegetables, legumes (beans, peas), fatty fish, cheese, poultry liver and fermented foods (yoghurt, kefir, kimchi);

a balanced diet.
supplementation - you can choose tablets, capsules or drops;
.
probiotics - especially those with Bacillus subtilis natto bacteria in the formulation;
.

.
What is the best form of vitamin K?
.
Each form of vitamin K has its own benefits for your body's health. The right vitamin K should be chosen based on your needs and clinical situation.

Vitamin K1 is essential for blood clotting and is often found in leafy green vegetables.

Vitamin K1 is essential for blood clotting and is often found in leafy green vegetables.
Vitamin K2 - particularly its MK7 form - is widely used in supplementation. It has beneficial effects on bone health, regulates the transport of calcium in the body, and may help prevent osteoporosis.

Always work with your doctor or nutritionist to choose the specific form and method of supplementation.
.
.
Are potassium and vitamin K the same thing?
.
No, potassium and vitamin K are two different substances and are not the same. Among other things, potassium is essential for maintaining electrolyte balance, regulates blood pressure and is involved in muscle function. Find out more about it in the article: Potassium in the body - properties, deficiency, sources.
.
.
.
Sources
.
.
See all
.
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