The importance of vitamin K for a healthy gut, and vice versa

Vitamin K, in turn, keeps the gut microbiome and intestinal mucosa healthy. Protein C, which is involved in wound healing, is important for repairing damaged intestinal mucosa and main- taining proper barrier function of the intestinal wall. Vitamin K is important for preventing or repairing a “leaky gut” (D’Alessio S, 2012).

Vitamin K supplementation (or a high dietary intake) improves the gut microbiome, inhibits intestinal inflammation, prevents or reduces gastrointestinal bleeding, improves vitamin D function in the gut, and protects against colon cancer (Lai Y, 2022).

Vitamin K deficiency

Vitamin K is a fat-soluble vitamin, but unlike other fat-soluble nutrients, it is stored much less in the body. Vitamin K1 is abundant in the diet, various forms of vitamin K2 are produced by intestinal bacteria, and MK-4 is produced in our cells.

Vitamin K is so important that the body recycles it to prevent deficiency, even when dietary intake is not optimal. As a result, most people have enough vitamin K to prevent bleeding.

However, this does not mean that you will have enough for all the other functions of vitamin K. In the case of long-term low dietary intake, disturbed gut microbiome, regular use of antibiotics and increased need (see box), there will not be enough for all the processes that require vitamin K. In this case, the vitamin will be directed to the most vital function, blood clotting. The other vitamin K-dependent proteins get the “leftovers”. This can have serious health consequences (see below).

Full activation of all vitamin K-dependent proteins requires at least 1,000 μg of vitamin K1 or 200 μg of MK-7 per day (Binkley NC, 2002; Vermeer C, 2012).