Log in/RegisterVitamin K is a fat-soluble vitamin that is important for many functions in the body. It plays a role in blood clotting, bone metabolism, and the regulation of blood calcium levels.
Main forms of vitamin K
Phylloquinone: This is the form of vitamin K that is found in plants, and it is the primary source of vitamin K in the diet. It can be found in green leafy vegetables, such as kale and spinach, as well as in some vegetable oils.
Menaquinones: This is a form of vitamin K that is produced by bacteria in the gut and can also be found in fermented foods, such as cheese and natto (a type of fermented soybean).
Benefits of vitamin K
Blood clotting: Vitamin K is necessary for the synthesis of proteins that are involved in blood clotting. Without enough vitamin K, the blood may not clot properly, which can lead to excessive bleeding or bruising.
Article continued below
Bone health: Vitamin K plays a role in bone metabolism and helps to prevent osteoporosis. It may help to increase bone density and reduce the risk of fractures.
Cardiovascular health: Some research suggests that vitamin K reduces the risk of cardiovascular disease by promoting proper calcium metabolism in the arteries and preventing calcification (hardening) of the arteries.
Cancer prevention: Some studies have found that vitamin K has anti-tumor properties and reduces the risk of certain types of cancer, such as liver and prostate cancer.
We should get enough vitamin K in the diet, as a deficiency can lead to problems with blood clotting and bone metabolism. Most people get enough vitamin K from their diet, but others may need to take supplements, such as those with malabsorption disorders or those taking certain medications that interfere with vitamin K absorption.
Vitamin K: daily dose
The daily recommended amounts of vitamin K for adults are:
Men: 120 micrograms/day
Women: 90 micrograms/day
For children, the recommended daily intake is based on age:
0-6 months: 2 micrograms/day
7-12 months: 2.5 micrograms/day
1-3 years: 30 micrograms/day
4-8 years: 55 micrograms/day
9-13 years: 60 micrograms/day
14-18 years: 75 micrograms/day
These recommendations are for healthy individuals who do not have any special nutritional needs. If you have a medical condition or are taking medications that affect your vitamin K needs, your healthcare provider may recommend a different daily intake.
Keep in mind that the recommended daily intake of vitamin K is a minimum amount that is needed to meet the basic nutritional needs of most individuals. Some people may benefit from getting more than the recommended amount, while others may need less. It is best to discuss your vitamin K needs with a healthcare provider or a registered dietitian.
Sources of vitamin K
There are several sources of vitamin K that you can include in your diet:
Green leafy vegetables: Leafy greens, such as kale, spinach, collard greens, and broccoli, are excellent sources of vitamin K. One cup of cooked kale, for example, contains more than 1000 micrograms of vitamin K.
Vegetable oils: Some vegetable oils, such as canola oil and soybean oil, are good sources of vitamin K.
Meat and poultry: Meat and poultry contain small amounts of vitamin K, but they are not rich sources of this vitamin.
Dairy products: Some dairy products, such as cheese and yogurt, contain small amounts of vitamin K.
Fermented foods: Fermented foods, such as natto (fermented soybeans), sauerkraut, and miso, are good sources of vitamin K2, which is a form of vitamin K produced by bacteria in the gut.
Supplements: Vitamin K supplements are available in both the phylloquinone and menaquinone forms. They can be taken as a standalone supplement or as part of a multivitamin.
