Vitamin K2 foods: natto, animal foods and fermented products

Compare the form as well as the food

NIH ODS lists 850 mcg MK-7 in a three-ounce natto reference serving. Its table also lists 13 mcg MK-4 in three ounces of rotisserie chicken breast, 6 mcg in three ounces of broiled ground beef and 4 mcg in one large hard-boiled egg. These are specified reference entries, not a complete K2 ranking or an assay of every product. [1]

Fermentation does not guarantee one amount

ODS notes that bacterial strains and fermentation conditions affect menaquinone forms and quantities. Cheese may contain menaquinones, but the word fermented does not establish a fixed K2 concentration or a guaranteed probiotic effect. Most leafy-green vitamin K values refer to K1, so they should not be relabeled as K2 when comparing foods. [1]

A hypothetical mixed-form food log

Imagine a meal log lists one egg and a natto serving. Keep the recorded MK-4 and MK-7 entries identified instead of treating the food names as precise assays. A high vitamin K food is not automatically appropriate as a sudden addition during warfarin treatment: ODS advises consistent intake and discussion of changes with the clinician. [1]

Hypothetical example — interpret a specific hypothetical label or comparison
ODS reference food and serving	Specified menaquinone amount
Natto,3 ounces	850 mcg MK-7
Rotisserie chicken breast,3 ounces	13 mcg MK-4
Hard-boiled egg,1 large	4 mcg MK-4

Vitamin K2 foods: natto, animal foods and fermented products — original article outline diagram — Original editorial diagram of this article’s sections; no product photograph or clinical finding is depicted.

Sources for this article

Vitamin K - Health Professional Fact Sheet
Source consulted: 2026-09-20. This is a reference resource, not a claim that we conducted the studies or tested a product.