<< Could you explain that please? I thought that the opposite was true. I have only been a vegan for less than a month, and I understand that I have stores of B12 in my body from a life of meat eating that will last me several years, but I was under the impression that I needed to get B12 through some artificial source(i.e. suppliments, fortified soy milk, Red Star nutritional yeast, etc.) Is there an active natural source that I could get instead? Jim >> That is what I was taught in grad school too, however it is not true. We store B12 for about 6 months, unless it is renewed. On observation pure vegans, of which I am one, who do not use any animal products do not get any signs of deficiency after years of having no animal sources of the vitamin. It turns out the B12 is made by normal symbiotic bacteria in the colon, and is absorbed there. So if you have healthful colonic bacteria, they make all the B12 you can use and you will never have a deficiency problem. Some vegetarians get it, those who use milk. Milk commonly has some residual anti biotics in it. These kill the normal flora in the colon. In fact any use of antibiotics can set you up for B12 deficiency, or damage to the distal illeum where it is absorbed. So under normal circumstances without taking antibiotics by perscription or in your food, you shouldnt have a problem. The symptoms of B12 deficiency include a numbness of all four distal appendages, feed, and hand. If you start having B12 deficiency problems by all means get some. I have been a strict vegan for 5 years, no supplementation, have no signes of any deficiiencies, in fact am the healthiest I have ever been. No colds, allergies greatly reduced, no headaches, and picture of health in general thanks Jerry