There are two main forms of vitamin K: phylloquinone (vitamin K1) which is found in green leafy vegetables such as lettuce, broccoli and spinach, and makes up about 90% of the vitamin K in a typical Western diet; and the menaquinones (vitamins K2), which make up about 10% of Western vitamin K consumption. The K2 forms can be synthesized from K1 by microflora in the gut and are also found in the diet in meat and fermented food products like cheese and natto, an especially rich source.
Vitamin K plays a key role in protecting skin elasticity and could soon be the latest nutraceutical appearing in savvy cosmetic lines. The research is just coming out that people who cannot metabolize vitamin K end up with severe premature skin wrinkling. Unlike vitamins A, E and D, Vitamin K is not stored in the body. After four to seven days, the body may become deficient for vitamin K.