I know some people on here might say Chlorella and Nori is not vegan, but I disagree. And I would much rather do food than injections or pharmaceutically synthesized forms of B12 (cyanocobalamin, hydroxocobalamin or methylcobalamin)
There is now reliable and credible evidence that Nori and Chlorella contain substantial amounts of human active B12!! here are the links, read 'em and weep meat eaters.
My fellow vegan and vegetarians,
There are more and more reliable studies coming out to prove that Chlorella and Nori contain reliable amounts of B12 WWOOOOHOOO!!
Spirulina, and all other algae contain too many analogues and will actually make b12 status worse (kelp,dulse, etc)
here are two:
I knew it all along!
E3 live as far as I know has improved B12 status in some people, in one or two studies, but it has still yet to be proven concretely!
But I haven't done more research, it may have more studies now...we will see...!!!!!!
Conclusion, ditch the spirulina, and dig the chlorella and nori! (nori has lower iodine levels so it is safe to eat larger amounts!)