Food production accounts for roughly ⅓ of total greenhouse gas emissions, meaning that small shifts in food choices can make a big impact. In this study, researchers calculated the greenhouse gas emissions of 3,233 different foods, as well as example diets from 212 adults. In general, diets that are better for people also tended to better for the planet. For example, people who kept to the recommended levels of sodium, saturated fat, and carbohydrates had lower greenhouse gas emissions than those who exceeded those levels. Further, non-vegetarian diets produced 59% more greenhouse gas emissions than vegetarian diets. When looking at individual food categories, 32% of diet-related greenhouse gas emissions were from meat, 15% from drinks, 14% from dairy, and 8% from cakes/cookies/confectionary.
PLoS One. 2021 Nov 23;16(11):e0259418. doi: 10.1371/journal.pone.0259418. (Rippin HL et al.)