A diet rich in peas, pulses and nuts can be incredibly low-carbon. Producing 100g of protein from peas emits just 0.4kg of CO2e. This is almost 90 times less than getting the same amount of protein from beef. Other pulses, such as lentils, have a GHG footprint of 0.8kg of CO2e. Tofu production, meanwhile, generates 2.0kg of CO2e per 100g – these emissions are mostly linked to the clearance of land for soy production, says Bridle.