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Vitamin K

life science Maturity 5-7 Next article →

Vitamin K is a family of nutrients that your body needs to stay healthy.

Phylloquinone structure
Phylloquinone structure

It is made of several parts called vitamers. These vitamers are fat-soluble, which means they dissolve in fat. Your body uses vitamin K for two very important jobs. First, it helps your blood clot so you do not bleed too much when hurt. Second, it helps control how calcium binds to your bones and other tissues.

Menaquinone
Menaquinone

Without enough of it, your blood cannot clot well, and you might bleed uncontrollably.

To understand how it works, you can look at how it helps proteins.

K1 vitamin Mechanism of Action
K1 vitamin Mechanism of Action

Some proteins in your body are called Gla proteins. These proteins need to be modified to work correctly. Vitamin K acts as a helper, or cofactor, in this process. In the liver, it helps a special enzyme change these proteins. This change allows the proteins to bind to calcium ions. If these proteins are not changed, it shows that a person might have a vitamin K deficiency.

There are two main natural types of this vitamin. Vitamin K1, also called phylloquinone, is made by plants.

Phytomenadione (vitamin K1)
Phytomenadione (vitamin K1)

You can find high amounts of K1 in green leafy vegetables like spinach or kale. Vitamin K2, or menaquinone, comes mostly from animal foods. You can find K2 in foods like eggs, poultry, and cheese. Some bacteria also make K2 during a process called anaerobic respiration. For example, a food called nattō is very rich in a K2 type called MK-7.

Different groups of people have different needs for this nutrient. In the United States, the National Academy of Medicine sets guides for how much to eat. For adult men, the suggested amount is 120 micrograms per day. For adult women, the suggested amount is 90 micrograms per day. These amounts are called adequate intakes. For babies under one year old, the amount is much smaller, between 2.0 and 2.5 micrograms per day. There is no set upper limit for how much vitamin K is safe to take.

Vitamin K is also used in medicine to help people in specific ways.

Vitamina K 20220202 122653
Vitamina K 20220202 122653

Newborn babies often get an injection of vitamin K1 shortly after birth. This is because babies may not get enough from their mothers. Some medicines, like warfarin, actually work by blocking vitamin K to stop blood from clotting too much. If someone takes too much of that medicine, doctors can use vitamin K as a treatment. Even rat poisons work by blocking this vitamin to stop blood from clotting.

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🖼️ Images & Media (5)
File:Vitamina K 20220202 122653.jpg
Vitamina K 20220202 122653.jpg
File:Phylloquinone structure.svg
Phylloquinone structure.svg
File:Menaquinone.svg
Menaquinone.svg
File:Phytomenadione (vitamin K1).jpg
Phytomenadione (vitamin K1).jpg
File:K1 vitamin Mechanism of Action.svg
K1 vitamin Mechanism of Action.svg
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