The tidbit is that chicken and eggs are not environmentally friendly, while beans tend to require lots of water. Neither has any D or B12. You need specificall

The tidbit is that chicken and eggs are not environmentally friendly, while beans tend to require lots of water. Neither has any D or B12. You need specifically liver or supplements for these. (Fatty fish is even less sustainable for D and not cheap.) That said you don't need too much methionine so can skimp on complete protein. Environmental chicken and egg? ;)