nutrient
Menaquinone-4 (MK-4)
A specific menaquinone form of vitamin K found in some animal-derived foods and formed in human tissues.
MK-4 is one member of the K2 group. Its chemical identity should remain separate from other menaquinones such as MK-7.
What the form means
MK-4 is a menaquinone with a four-isoprenoid side chain and one member of the vitamin K2 group.
Forms
Menaquinone-4 (MK-4) is a form of Vitamin K.
Menaquinone-4 (MK-4) is a named chemical form within its parent vitamin family.
Worth knowing
A specific K2 form. MK-4 is a menaquinone found in some animal-derived foods and formed in human tissues from phylloquinone. “K2” on its own does not tell you whether a product contains MK-4 or another menaquinone.
A closer look
The body can make some MK-4
MK-4 is unusual within the K2 group because the body can make it from K1 through a tissue conversion process. That pathway is different from the bacterial production associated with many longer-chain menaquinones, so K2 should not be treated as one uniform metabolic source.
References
Source-checked local draft.
Human editorial review pending.