@mrmacabre Thats great that u eat plenty of animal protein, the source of vitamin B12 (cobalamin). Great up to middle age.
Alcohol numbs billion of tiny villi lining our 20 ft long intestine inner wall, hence reduced thru the wall absorption. Then our elderly stomach is smaller, less acid. The acid extracts B12 from food. I am 83 and take 50 micrograms B12 daily. Methylcobalamin is the best of the 3 types. Am not waiting for my doctor to give me monthly B12 injections. 3 months ago my dr, wrote on my file " non drinker, " am proud of that. Good luck.