I am vegan. People often assume that veganism brings B12 deficiency, but it doesn't - you are no more likely to suffer with this as a vegan than on any kind of diet. It's modern farming practices that are responsible, because the soil is impoverished now and we wash all our vegetables to death. Our ancestors ate dirt, basically, and the dirt was full of the bacteria that B12 comes from. Grazing animals, of course, took large quantities of it in with the vegetation they ate, so eating their flesh gave humans B12. Nowadays - not so much. In fact, most animals receive supplements, because they are not feeding naturally at all and their fodder will be just as depleted of useful vitamins as our plant foods are.
This means that most people probably need to supplement with B12, no matter what or who they eat. I have only once had severe anaemia and that was when I was going through the menopause. In fact I had to have a blood transfusion - this was in 1999 when I was 44. This was way before I went vegan.
I take a supplement pill occasionally - usually when I am away from home and not eating my regular sorts of foods. The last blood test I had, everything was fine. I find being vegan is actually extremely healthy, which is a benefit, because I did it for ethics. I have vitamin fortified plant milks everyday as a matter of course - on my cereal and in my tea and coffee, as many of these dairy alternatives come automatically with it added -so actually I scarcely ever think about or focus much on B12. Absorption is sometimes a problem for some folk - and that is not something over which we have much control.