Just last week, I wrote about how processed vegetarian protein products aren’t necessarily greener than local, organic animal proteins. This week, a new study commissioned by the eco-nonprofit World Wildlife Federation came out on the same topic — confirming that vegans are not always greener than locavoring omnivores.

To be clear: This doesn’t mean you should go buy a hunk of factory-farmed steak.

In fact, if locavoring omnivores and vegans can agree on one thing, it’s this: Americans need to eat a more veggie-based diet that shuns factory-farmed animal products. After all, even Michael Pollan — arguably the most famous eco-omnivore right now — big ups veggies in his haiku-esque green eating mantra: “Eat food. Not too much. Mostly plants.”

What the new study basically points out is that eating green isn’t simply about picking a vegan, veg, pescatarian, or omnivore diet. It’s about paying attention to what you’re eating specifically — where it comes from, how it was grown or raised, how much it was processed, and how much it traveled to get to your plate.

The study, conducted by Cranfield University, basically found that processed veg proteins that traveled long distances were sometimes more harmful to the environment than local animal products. Unfortunately, I’ve been unable to find the study itself online, and have had to rely on The Telegraph UK’s article about the study, which reports:

The results showed that the amount of foreign land required to produce the substitute products – and the potential destruction of forests to make way for farmland – outweighed the negatives of rearing beef and lamb in the UK….

Meat substitutes were also found to be highly processed, often requiring large amounts of energy to produce. The study recognised that the environmental merits of vegetarianism depended largely on which types of foods were consumed as an alternative to meat.

Note, again, that the big carbon footprint of the veg proteins had to do mostly with processing and travel miles. The comparison being made here isn’t between the average vegan and the average omnivore (who likely consumes factory-farmed beef, which is about the ungreenest protein source), but between the imported veg-meat addicted vegan and the locavoring omnivore.

This means that if you’re eating highly-processed veg meats imported from Taiwan most days, you diet’s not greener than your friend who gets organic, free-range eggs from the local farmers’ market. On the other hand, if you’re a vegan who sticks to tofu grown and made in the U.S., or legumes grown as locally as possible that you buy dry and cook at home, your carbon footprint will likely be lower than most omnivores.

According to The Telegraph, “The National Farmers’ Union said the study showed that general arguments about vegetarianism being beneficial to the environment were too simplistic.” I completely agree with this opinion. Eating green isn’t as simple as short mantras like “Go Veg!” A sustainable diet requires more nuanced thinking, and a stronger emphasis on local foods.

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