Vitamin K
filochinon / menachinon · last AI check: 2026-07-19
In short
Needed for blood clotting and bone formation. Occurs in two forms: plant-derived (K1) and bacterial (K2).
What it does in the body
The sentences below are officially authorised EU health claims.
Vitamin K contributes to normal blood clotting EU health claim
Commission Regulation (EU) No 432/2012 of 16 May 2012, Annex — list of permitted health claims · register entry: 124, 126 · EFSA opinion: 2009;7(9):1228
Condition of use on a product: The product is at least a source of Vitamin K.
Vitamin K contributes to the maintenance of normal bones EU health claim
Commission Regulation (EU) No 432/2012 of 16 May 2012, Annex — list of permitted health claims · register entry: 123, 127, 128 · EFSA opinion: 2009;7(9):1228
Condition of use on a product: The product is at least a source of Vitamin K.
How much you need
| Country / organisation | Group | Value | Type |
|---|---|---|---|
| EFSA | adults | AI Adequate intake — an approximate value used when data are insufficient to set an exact requirement (RDA). | |
| FAO | adult men | RNI Reference nutrient intake — the RDA equivalent in WHO/FAO, UK and Philippine terminology. | |
| NASEM (US/CA) | adult men | AI Adequate intake — an approximate value used when data are insufficient to set an exact requirement (RDA). | |
| Philippines | adult men | AI Adequate intake — an approximate value used when data are insufficient to set an exact requirement (RDA). | |
| Poland | adults | AI Adequate intake — an approximate value used when data are insufficient to set an exact requirement (RDA). | |
| Switzerland | adults | AI Adequate intake — an approximate value used when data are insufficient to set an exact requirement (RDA). |
Reference values from different countries are not directly comparable — they differ in definition and age group. How to read reference values →
Every value states its source — click it to see the document, location and link.Data and content are prepared and cross-checked against source documents by several independent AI models. They have not been audited by a human editor.Before citing a value, check it in the source document — verification is automated (AI), not editorial.
Worth knowing
Vitamin K1 (phylloquinone) comes mainly from green leafy vegetables and is the form most often studied in dietary reference values. Vitamin K2 (menaquinones) is formed with the involvement of bacteria — partly in the human gut, partly in fermentation processes (e.g. in natto) — and is distributed differently in the body's tissues.
People taking anticoagulant medication from the vitamin K antagonist group (e.g. warfarin) should keep their vitamin K intake steady rather than variable — a sudden increase in green vegetables in the diet can affect how the medication works. This is a topic for a conversation with your treating doctor, not a decision to make on your own.
Where to find it
green leafy vegetables (kale, spinach, broccoli) · vegetable oils · natto and fermented soy products (K2)
This material is for information and education. It does not replace advice from a doctor or dietitian. For health matters, consult a qualified medical professional.