If you’re finding it tough to go vegan or vegetarian, here’s another eco-friendly incentive: A new Oxford University study published in the journal Climatic Change reveals that the food carbon footprint of someone who skips the burgers and baby back ribs is half that of a meat eater.

It’s a common sense idea and one that’s been raised plenty of times by environmental activists. After all, raising animals for human consumption is a resource-intensive process, and the 88 million belching cattle across the United States release a boatload of smog-causing methane gas into the atmosphere. However, nailing down the specific impact an individual’s food choices makes has always been tough for scientists.

That’s why the Oxford researchers tracked every single bite consumed by over 55,000 British omnivores, pescetarians, vegetarians, and vegans aged 20 to 79. Through that process they were able to determine exactly how many pounds of CO2 went into producing the food they ate.

People who the study identified as heavy meat eaters (they downed a mere 3.5 ounces of meat every day) had a daily footprint of a whopping 15.8 pounds of CO2. Cutting out the burgers and sticking to fish took that footprint down to 8.6 pounds of CO2 per day.

Surprisingly, the researchers found that being a pescetarian has almost the same positive environmental impact as being a vegetarian. Not eating meat but still downing eggs and dairy produces 8.4 pounds of the greenhouse gas on a daily basis. However, vegans are by far the most environmentally friendly, producing only 6.4 pounds of CO2 per day.

Of course, given how overfished our oceans already are, if the whole planet turned to pescetarianism, we could see absolutely nothing swimming in the sea. Everyone going vegan might not be the most realistic option, either. As with everything, moderation is the key. “Reducing the intake of meat and other animal-based products can make a valuable contribution to climate change mitigation,” wrote the study’s authors.