There are two sources of this essential vitamin, including vitamin K1, or phylloquinone which is primarily found in green leafy vegetables. Phylloquinone is absorbed in the jejunum and ileum and is primary stored in the liver. The second one is vitamin K2 or menaquinone which is synthesized by certain intestinal bacteria. Menaquinones are absorbed from the distal bowel and stored in the liver.
Specifically, Bacteriodes as well as a few other genera, produce this vitamin. In certain individuals bacteria supply up to 50% of the body’s total vitamin K requirements.
A decrease in dietary of vitamin K2 and/or a reduction in vitamin K2 production by gut bacteria can lower vitamin K levels. Antibiotics can destroy not only harmful digestive tract bacteria, but also the beneficial intestinal bacteria that is needed to create vitamin K.
The primary role of vitamin K in the body is in blood clotting. Vitamin K is also important to bone health. It assists in the mineralization of bone with calcium, thus keeping bones dense and strong.
Intestinal bacteria produce vitamin K2
