Question: I’ve been reading about the health benefits of vitamin K in preventing heart disease and osteoporosis; however, it is in very few foods and the supplements all seem to be made from natto (fermented soy). Is it safe to take a supplement made from natto, or will this cause excitotoxicity?

Dr. Blaylock's Answer:

Vitamin K is indeed a vital nutrient and has more functions than just blood clotting. For example, it plays a role in preventing osteoporosis, reduces inflammation, and stimulates the production of mitochondrial energy.

Fortunately, it has no toxic effects even in very high doses — that is, it will not cause excess clotting of the blood. As for it being made from natto, the vitamin K is concentrated and any traces of the dietary excitotoxin glutamate from the soy are far too small to be of any consequence. (Dietary excitotoxins can produce widespread inflammation in many tissues.)