Vitamins K1 and 2 are “koagulation” vitamins, required for blood coagulation. They are normally produced by bacteria in the large intestines. They are normally in sufficient quantities except when there is damage to the intestines which hinders absorption or when broad spectrum antibiotics are in use. Osteoporosis and coronary heart disease are strongly associated with low levels of vitamin K2. There are also synthetic versions which are used by the pet food industry.

Excellent sources of vitamin K include spinach, Brussels sprouts, Swiss chard, green beans, asparagus, and broccoli, kale and mustard greens. Very good sources include green peas and carrots. Eggs and cheeses are also good sources. The ideal source of K2 is natto, the unpalatable, gooey, slimy mass of fermented soybeans that Japanese eat and has been held responsible for substantial decreases in osteoporosis and bone fractures of aging. Natto has an ammonia-like bouquet, in addition to its phlegm consistency that makes it virtually inedible to anyone but native Japanese.