You try to do everything right. You drive an electric car, you have a small collection of LED lightbulbs and Energy Star-rated appliances, and you’ve been known to buy carbon offsets as Christmas presents. But according to a new study, that could all be undone by something as innocuous as that sandwich you just ate for lunch.
Researchers at the University of Manchester decided, for some reason, to calculate the carbon footprint of Britain’s most popular sandwiches, and after doing some equations involving the ingredients in “40 different sandwich types, recipes and combinations,” have determined the worst offenders. The most environmentally-unfriendly variation is the “all-day breakfast” sandwich—with egg, bacon, and sausage—and, according to their calculations, each sandwich generates 1,441 grams of carbon dioxide equivalent, roughly the same as driving your car for 12 miles.
Pork products, including bacon, ham and sausage, were the worst all-around, followed by sandwiches with cheese or prawns. The ingredients themselves weren’t the only things the researchers considered; they also looked at the production cycle for each ingredient, the manufacturing process for the sandwich packaging, the methods used to transport them to the point of sale, the carbon emissions from keeping them refrigerated, and the food waste generated at all points in the supply chain (including the uneaten parts you emptied into your office trash can).
The University cited the British Sandwich Association’s statistics, which said that more than 11.5 billion sandwiches are eaten annually in the UK—and at least half of those are bought in shops, grocery stores, and restaurants rather than made at home. “Consuming 11.5 billion sandwiches annually in the UK generates, on average, 9.5 million tons of CO2 eq., equivalent to the annual use of 8.6 million cars,” Professor Adisa Azapagic said.
Azapagic and her team said that if you really want to further shrink your carbon footprint, you need to make your sandwiches at home and avoid “lettuce, tomato, cheese, and meat.” (Alright! Who wants a bread sandwich on bread?)
It’s a big study with buzzed-about findings, but not everyone is buying it. First, although it’s the first all-sandwich study of its kind, other organizations have been pointing out the environmental impact of consuming meat products for years. Even National Geographic has pointed out that eating a pound of beef is the carbon-emitting equivalent of burning a gallon of gas.
The American Council on Science and Health wrote its own brutal takedown of the study. “Don't you find it astounding that this was the first study of its kind? I just don't get it. How did science possibly miss out on this until now?” Dr. Josh Bloom wrote. “What else was missed?” (He also suggested that, if this study was done, then maybe scientists could turn their attention to researching "How to talk to your potholders.")
But perhaps no group of people was more dismissive of the findings than the commenters on conservative website The Blaze, which appears to have written about the study purely so it could point out that President Trump had pulled out of the Paris Climate Accord and further undone much of the Obama administration’s work on climate change.
“Only in GB could they come up with something even more stupid than our trolls’ belief in global warming,” one scholar commented. “They won’t be happy until we are eating only organic grasses and then all women forced filed onto an abortion table,” dano1 added. And Triker246 declared that “a load of liberal crap, is what is causing global warming (literally).”
Weirdly, the University of Manchester didn’t reach any of those conclusions. Especially not while ordering a sandwich to go.
This article originally appeared on Munchies US.