Hi Stefan,
If the ill health was caused by b12 deficiency, then this is not
surprising
and not a good reason to eat animal foods. b12 would in a natural
environment be supplied by the unwashed food and by our gut flora as
well.
Our modern lives interfere with this natural process and can leave
some
deficient. The diet is not at fault here. Yearly b12 tests are
recommended
or supplementation once a week (by Joel Fuhrman MD).
Meat eaters have a higher incidence of b12 deficiency than vegans BTW.
Cheers
Mike.