Matty,

Many people are born with the seeds of severe B12 malabsorption later in life. And I am one who has family evidence of this. My mother malabsorbed moderately, I suspect my dad may have, I developed severe malabsorption, and two of my adult children developed severe malabsorption at a much younger age than I had. I spoke with a researcher, and he said "these things mutate."

Also I have found written material discussing the increasing severity developing in some subsequent generations (as my family illustrates).

I hope he will increase that B12 dose to 1000 mcg. If he malabsorbs severely, or is heading in that direction, that is a much better dose to insure he gets what he needs.

rose