Thank you for the comment! Your argument about social desirability bias changed my mind. I hadn't considered it, but you're definitely right to point out that health issues are a more socially acceptable excuse for no longer committing to an ethical cause compared to taste or convenience.

I also agree with you that we need strategies to make it easier for people to not mess up. On an individual level, getting people to track their vitamin intake and to track nutrients with Chronometer is good advice, though I'm not sure how scalable it is. On a societal level, we would probably need to legally mandate B12 enriched rice or bread in the same way we do that with iodine in salt. I think another thing that would help would be to normalize vegetarian proteins like tofu, lentils, and beans in Western countries.This way people don't have to make as much of a diet switch when they stop eating meat.