The CDC has looked into a <a href="http://story.news.yahoo.com/news?tmpl=story&u=/nm/20030130/hl_nm/infants_diet_dc_1">pair of cases</a> where strict vegan mothers (no fish, milk, eggs, etc) breast fed their babies who later had developmental problems from a lack of vitamin B12. Considering that a strict vegan diet has almost no B12 in it at all, and most vegans use artificial (i.e. man-made) vitamin supplements, is it possible to make a case that humans in their natural environment as Nature intended are not meant to be vegetarian? I bring this up because I have a few people I know who are of the most militant sort of vegan, to the extent that they frequently attempt to make the carnivores in the crowd uncomfortable when we go out to grab a bite to eat at a restaurant. These same few people also tend to think of the technological society we live in as a blight upon the face of the earth, and that we should go back to farming the simple way. However, the irony here seems to be that in order for these folks to live their eating lifestyle AND have healthy children, they need the technology to make B12 supplements. So, is this a conclusive proof that Man as a species existing in the wild just wasn't meant to live without critters in the diet?