Peter Brandt wrote: > I am in the process of contacting the major spirulina producers in the US > to get their feedback on the B12 analogue issue. You might ask about the mechanism of B12 inhibition. Is it irreversible or competitive. It is possible that with enough real B12 the analoques do not cause a problem. It is also possible that the analogues form a stronger bond then the real B12 in which case adding B12 will have a minimal effect. It seems that only a small amount of B12 is necessary for normal functioning which means to me that there are only a few active B12 sites available. This means to me that even a small amount of B12 analoques could be a problem. Frank.