The results were a little surprising. The meat with the smallest carbon footprint was ... canned tuna. The meat with the biggest was lamb, then beef, then ... cheese, which created more overall emissions than pork.
Lentils had the greenest carbon footprint, with tomatoes running a close second and 2 percent milk third-to-greenest.
The study gets to a pretty granular level, and there were more surprises there. Forty-four percent of farmed salmon is thrown away, accounting for its high post-farmgate carbon footprint. Five percent of meat is thrown out by retailers. Composting meat at home doesn't significantly reduce its carbon footprint. Less dense cheeses like cottage cheese have less impact because they require less milk.
There are even more micro details, and if you want to read the results, go here.
The takeaway was this: Meatless Monday is good for reducing carbon footprint. A four-person family skipping meat and cheese one day a week is the environmental equivalent of not driving for five weeks. Or skip a single burger each week and that's like line-drying your laundry half the time, or driving 320 fewer miles.
Almost as important as doing without was the way you can shop: buying only what you need prevents loss to "plate waste" and spoilage. So if turkey lunch meat, pork chops, or even peanut butter and yogurt, just sit in the fridge or cabinet until they spoil, you and the environment are better off leaving them with the retailer.