Researchers at the University of Manchester determined the carbon footprint of 40 commercial and home made sandwiches.

Commercial sandwiches ranged from 731 g of CO2 for an egg and cress sandwich to 1441 g CO2 for a bacon, sausage and egg sandwich. 1441 g of CO2 is the equivalent of the emissions of driving a car 12 miles.

Home made ham and cheese sandwiches ranged from 399 to 843.