Mr. Green is busy on his world-wide publicity tour for his new book. In the meantime, here's a Mr. Green classic column from January 2007.
Several readers have written asking why, although I recommend limiting meat consumption, I don't come out and demand total abstinence. Well, call me conservative (ooh, how that would hurt), but at this point, I am not convinced that completely eliminating meat and fish from our diets is best for the environment. I've heard the main arguments--(1) that it takes eight or more pounds of grain to produce a pound of meat, (2) that livestock raising pollutes air and water, and (3) that eating meat violates animal rights--and I'll try to address them one by one.
The grain-to-meat ratio is not as inefficient as it may first appear. The primary grain fed to cattle is corn, which has a relatively low protein content. A pound of beef contains three or four times as much protein as a pound of corn, and unlike corn, it's complete protein. In addition, meat contains vitamin B12 and certain micronutrients not present in grains. It's the old apples and oranges problem--grains and meat are just not the same thing.
Also, not every pound of an animal is produced by feeding it grain. Cattle, for example, put on a good deal of their weight from hay and pasture. Besides, the overfeeding of grain is more a result of popular taste than agricultural necessity. Consumers have been taught to favor fatty "marble" in their meat, which is produced by grain feeding. Some environmentally friendly producers get tasty results by grazing their cattle and cutting way back on the grain.
The simple weight-to-weight comparison also fails to account for the role of livestock in a healthy agriculture. Animals produce manure, which is (and has been for millennia) a very important source of fertilizer. Without livestock, more chemical fertilizers would have to be used. Farm animals also convert nonedible grasses into edible food without the need to plow up land (a major cause of soil erosion). Cattle, in particular, provide another source of fertilizer, since the alfalfa they eat fixes nitrogen in the soil.
This argument also ignores the fact that from time immemorial, food has not been the only purpose of livestock. Any meaningful comparison has to take into account the byproducts of meat production, including leather (a $2 billion industry in the United States). As far as I know, no one has looked closely enough at the entire picture, holistically examining all environmental, agronomic, and economic aspects of livestock growing for different ecosystems. Until they do, and until I see compelling evidence for zero meat consumption, I'll stick with the less radical stance of limiting--not eliminating--meat eating.
The second major argument against meat is that raising livestock pollutes. Yes, indeed it does. Terribly. However, this does not have to be the case. There is nothing intrinsic to livestock production that necessitates the cramped feedlots, hog and chicken factories, and bad grazing practices so notorious for their environmental damage.
The main reason livestock is being raised in this filthy and brutal way is to meet the U.S. demand for a huge quantity of cheap meat. This is exactly why I recommend eating a lot less meat. By eating less but paying more per pound, we could then support farmers who raise meat in an environmentally beneficial way and treat their animals humanely.
People and animals are both victims of the country's long-standing "cheap food" policy that mostly benefits agribusiness. But that's a whole nother topic. (Additionally, we can't stop meat production just by fasting from meat. Whether we like it or not, the worldwide demand for meat is increasing, and you can be sure that many countries we export it to would not apply any pressure for environmentally sound production. Italy, for example, famed for its healthful diet, now consumes ten times as much meat as it did 50 years ago, and it's hard to see what would stop such a trend in industrializing countries like China.)
The third case made against meat, the animal-rights argument, is certainly valid when creatures are made to suffer unnecessarily, as in factory farms. This, however, is again a question of method. There is no reason livestock has to suffer so that McDonald's can sell more bacon burgers--no reason, that is, except to keep those burgers cheap. To stop this suffering, we have to demand a change in the method of production. This is happening, though much too slowly.
Of course, some animal-rights advocates would argue that we have no moral right to take the life of any creature to feed ourselves. I find it hard to accept this argument for two reasons: First, human beings have clearly evolved to consume meat and have probably done so for several million years. Biologically speaking, we are just another type of predator, taking prey just as a shark eats other fish or a cougar eats a deer. The animals we now slaughter for food would be quickly eaten by other predators if we turned them loose. What would we do then to protect their "rights," kill the predators? Philosophically, I find it rather anthropocentric for human beings to extend human laws against homicide to other species, when so many are in the evolutionary business of killing.
Secondly, the brutal truth of agriculture is that you have to kill to be a vegetarian. I smash snails to keep them from eating my vegetables. I don't shoot squirrels, even though they steal my figs and guavas, but I'd be rather pleased if a predator carried a few of them away. Let's face it: Any farmland displaces myriad creatures or requires them to be chased away, fenced out, or killed, so even the strictest vegetarian or vegan has blood on his or her hands. Ecologically, I suppose the purest thing we could do would be to give up all forms of agriculture and revert to a hunting culture. But going full circle back to our predatory beginnings would leave little time for us to engage in these kinds of debates.