According to a new study, lettuce produces more greenhouse gas per calorie than bacon, so the media was very fast to blame vegetarians for “killing the planet.” But are these articles right?
Is a vegetarian diet bad for the environment? Logic says it isn’t.
A team of researchers from Carnegie Mellon University conducted a study from which they drew the conclusion that the nutritional guidelines to be issued by the U.S. Department of Agriculture, which recommend a diet based on vegetables, fruits, seafood and dairy, is actually harmful for the environment.
In their study, the researchers looked at the resources needed to produce a calorie of certain vegetables versus those needed for a calorie of pork of chicken meat. They concluded that, in the case of lettuce, each calorie “costs” more (in terms of environmental damage) than each calorie of bacon.
The environmental costs are calculated in terms of greenhouse gas emissions produced by growing, processing, transportation, storage, water, energy use and anything else needed to get a product on the shelves.
However, they failed to consider what’s actually being produced; it’s lettuces and pork, not calories. So let’s look at it from another perspective: a green leaf of lettuce has 15 calories per 100 grams while 100 grams of raw bacon has 417 calories. More than that, lettuce doesn’t require any additional preparation,whereas bacon cannot be eaten raw and a lot of additional resources are being spent to prepare it and finally reach 548 calories per 100 grams of baked bacon.
So, looking at the caloric intake, researchers are missing the bigger picture. And it makes it really wrong to say that lettuce is guiltier for a bigger amount of greenhouse gas emissions than pork, since they would have to exist in the same proportion on earth to make a proper comparison.
But, let’s just imagine that a pig weighs 300 lbs. while a big iceberg lettuce head weighs 1.5 lbs. That means about 200 lettuce heads would have the same weight as a pig. In terms of calories, one 1.5 lb lettuce head has about 102 calories, so 200 lettuces would have 20,454 calories. On the other side, one pig of 300 lbs. would have 747,272 calories.
Or, to put it simply, 3,600 grams of lettuce have an equal amount of calories as 100 grams of pork. So if the total mass of lettuces isn’t 36 times heavier than the total mass of pork on this planet, it is wrong to say that lettuce poisons the environment more than pork.
More than that, not all vegetables and fruits are responsible for the same amount of greenhouse gas emissions. Soy and grains, highly consumed by vegetarians, are known to have some of the lowest emissions.
In conclusion, if you want to save the environment don’t throw the lettuce for the pork but the other way around.