As far as incidence of B12 deficiency, I would expect it to be highest in
octo lacto vegetarians as their diet is very low in B12 + they destroy their
ability to make it with exogenous antibiotics. So they are and often should
be B12 deficient.

Next would be vegans who are exposed to antibiotics or for some reason have
problems with their GI flora. These would compete with meat eaters who also
eat eggs and milk.

Next would be healthful vegans, and meat eaters who do not eat milk or eggs,
or rarely do.

Last would be organ eating meat eaters who have a very high exogenous source
of B12, and do not drink milk or eat eggs, the most common sources of
antibiotics in the diet.

this is what I would expect. I do not have the data. As far as deficiency
goes, I think that is the key. Most vegans have enough 12 but not an excess
as would an organ eating meat eater.

I had the same problem with another blood test. One doctor thought I had a
serious disorder because my white blood cell count is typically far below the
minimum in normal blood test. The problem is that as a living foods vegan, I
have very little immune response to my food, and as most living foods vegans
my white blood count is below normal when I am in good health, as are my
allergies to allergens. It just means that the test and the norms for it are
set for people not living as I do, or as vegans do, not that we have a
disorder. Our immune systems are usually not as active as meat eaters except
when we are sick. Then they respond better. Medical testing often involves
averages set arbitratily, usually on healthful young volunteers in colleges,
who are living poorly, but still in great health because of their age.

The key to knowing whether to supplement  B12 is symptoms. Unfortunately if
you are deficient, you may develope damage before symptoms. For that reason
it is important to eat living high healthful bacteria foods to be sure that
there is good flora in the gut. If you want to supplement B12 it is fine. I
don't. But that is my choice, and I have had no exogenous sources of B12
since 1992.

thanks

Jerry
Dr Jerry Knox BA, DC
http://www.lifeknox.com