The notes on this page demonstrate that objections to veganism based what is natural are not germane to the case for veganism, and even if they were, they are still dubious.
The notes on this page show that any inference about the naturalness of a vegan diet based on the need for B12 supplementation is both irrelevant and fallacious.
The notes on this page offer several points to consider when evaluating the objection to veganism and animal right based on the presence or absence of a soul.