New research published in the Journal of Cleaner Production reported that, “From 2003 to 2018, the mean GHG emissions associated with the US diet fell by more than 35%, from 4.02 kg CO2e per day per capita, to 2.45 kg CO2e per day per capita, despite average caloric intake remaining relatively stable over the same period. Average beef consumption declined 40% per capita over the study period, which contributed to more than 50% of the observed GHG savings in the diet over the study period.
All demographic variables included in this analysis (age, gender, race/ethnicity, and ratio of family income to the federal poverty level) exhibited a reduction in GHG emissions associated with their diets. However, GHGs and overall rate of change differed across demographic subgroups. Black women had the lowest GHG emissions associated with their diet, 1.92 kg CO2e per capita per day. Men aged 20–34 had the largest rate of reduction in GHGs associated with diet changes, with an average annual decline of 210g CO2e per day per capita over the study period.
Despite GHGs associated with the US diet falling over the last 15 years, the US diet is still exceeding established GHG limits to meet global targets, such as the Paris Agreement. Additional research is needed to better understand motivations and drivers that have reduced emissions in the diet over this period, particularly in demographic subgroups that showed both low impact and a rapid decline in emissions.”
Citation: Clare Bassi, Rachael Maysels, Rob Anex, Declining greenhouse gas emissions in the US diet (2003–2018): Drivers and demographic trends, Journal of Cleaner Production, Volume 351, 2022, 131465, https://doi.org/10.1016/j.jclepro.2022.131465.