Menaquinones, Bacteria, and Foods: Vitamin K2 in the Diet

Abstract

Vitamin K2 is a collection of isoprenologues that mostly originate from bacterial synthesis, also called menaquinones (MKs). Multiple bacterial species used as starter cultures for food fermentation are known to synthesize MK. Therefore, fermented food is the best source of vitamin K2. In the Western diet, dairy products are one of the best known and most commonly consumed group of fermented products.Although intensive research on metabolism and the biological effect of vitamin K2 continues today, data about vitamin K2 production and content in foods remain scarce. Dietary recommendations are still based on the classic role of vitamin K as an enzyme cofactor for coagulation proteins and do not consider differences in bioavailability and bioactivity between the various MKs and the possibly higher requirements for health effects apart from coagulation, such as bone or cardiovascular health. Here, we provide a global view of foods rich in vitamin K2 and their interactions together with other nutrients in selected health effects such as bone and cardiovascular health.

Transplantation of an obesity-associated human gut microbiota to mice induces vascular dysfunction and glucose intolerance

“…Another interesting observation was the association of several Bacteroides species, such as B. ovatus, with a lean microbiota and observation of a positive correlation between Bacteroides and EDD, and an inverse correlation to glucose AUC. Bacteroides have a well characterized pathway to synthesize menaquinones (Vit K 2 ) 30 and it was recently demonstrated that the gut microbiota regulate endothelial function and blood pressure via a vitamin K 2 -dependent pathway. 31 It is interesting to speculate whether loss or reduction of bacterially-synthesized K 2 may have driven the results observed in this study.…”

Role of Vitamin K in Intestinal Health

“…Bacteria exert critical effects on the onset and perpetuation of gut inflammation in IBDs ( 125 ). The intestinal microorganism or bacteria present in food may produce bacterially synthesized menaquinones which contribute to K 2 requirements in human ( 126 ). Small-intestinal bacterial overgrowth (SIBO), associated with low circulating levels of K 2 ( 127 ), is involved in increased plasma levels of inactive MGP and results in alteration of K 2 metabolism ( 128 ).…”

The structure of nutrition of Russian students as a risk factor for the development of nutritional diseases

“…К основным источникам K 2 относят ферментированные продукты питания, мясо и молочные продукты. Основным способом обеспечения организма витамином К у здоровых людей является пищевой, так как снижение потребления витамина К с пищей не компенсируется кишечными менахинонами, что, вероятно, связано с лучшей биодоступностью филлохинона [31,32]. Вероятно, необходимый уровень поступления витамина К для сохранения соответствующей функции свёртывания крови у студентов достигается потребляемым набором продуктов [1,4,10,11], так как данные о дефиците этого витамина у здоровых взрослых отсутствуют.…”