For me, one of the best things about eating a plant based diet is getting all the vitamins and minerals I need through whole foods. Except for Vitamin B-12. B-12 is not found in plants or technically animals. Its found in microbes in the ground.
These bacteria grow in the guts of animals, which is why their bodies and products can be a source of this vitamin. Our herbivore primate cousins get all they need ingesting bugs, dirt, and feces, and we may once have gotten all we needed by drinking out of mountain streams or well water. But now we chlorinate our water supply to kill off any bugs. - Dr. Michael Greger, NutritionFacts.org
So by eating meat we then get our needed B-12. However, by not eating meat now, I do have to supplement this vitamin with a daily pill. But why? Why is this one vitamin so important?