Yes, I have. Quite simply, to get a given quantity of usable protein by passing plant stuffs through an animal takes three to five times as much useful material as eating it direct, depending on whether you're talking about chickens or cows. (This obviously does not apply to sheep on the hills eating grass; but then most of the cows and chickens we eat in the west are fed on grains and pulses.) Thus, crudely, we have a choice: a quantity of land A for vegetables and say a quantity 3B or 4B to sustain meat; or a quantity of land A for vegetables, and a quantity of land B for more vegetables...Aelfarh wrote:Have you taken into account the increase on fields needed to get enough plants that substitute the nutrients given by meat, dairy and all other animal-related products? and the damage that agriculture do to the lands?
Or maybe, slightly more than A + B; but I certainly can't see that a largely vegetable diet could ever require more land per person than a diet high in meat. After all, if you're getting your protein via an animal, inevitably what you get out is less in total than what you put in, even if it may be more concentrated or (to some minds) more palatable.
Which is very different from the common subsistance situation where the chicken and the pigs get the leftover scraps and the sheep or the goat is put out on land which can't otherwise be farmed. This is (i think) probably the most efficient of all in a temperate climate; though it wouldn't suit a veggie like me!