I was a heavy meat eater for 15 years. Meat and only meat 6 meals a day quite often. This causes intrinsic factor to not be produced so that b-12 is not absorbed and caused me to be diagnosed with 2 diseases I have reversed and continue to rebuild from the damage.
B-12 is lacking most often in vegan diets follwed secondarily by vegetarian ones. If we (vegetarians) were not deficient before attempting vegetarianism, then we seem to be ok with the small trace amounts in food after all only 3 mcg I believe is required a day. However those of us who are whole body depleted (and you do not realize this for many years) do not get enough from plant sources. I always craved eggs cheese and dairy for about a month and then could go for another 4-5 without,. I finally figured out it was b-12 deficiency. I did not crave these things when i was taking kefir last year as the by product of fermentation is a synergistic increase in B-12. It is also said and contested I guess that We can produce b-12 also in the gut. I care less about what Science says but rather look at all the vegetarians in history who lived by example.
I've been a big bible reader since about the age of 4, and studied it quite extensively. I gaven sermons in church starting I think at 12 because I had different understanding reading a verse than most people and they respected that as something they could not initially see. (I could never see the common interpretations that people have so I understand). I have many ancient translations and versions of which are more accurate and portay greater meaning than the popular versions of today. Amazing how the interpolation of words can cause many to go astray.