Changes in diet have often been proposed as a way to reduce overall greenhouse gas emissions. However, there has not been much research about the affordability and feasibility of such changes.
A new study provides a comprehensive estimate of greenhouse gas emissions generated by consumer food purchases in the U.S. Unsurprisingly, the study found that if Americans directed more of their food purchases away from meats and other animal proteins, they could help reduce greenhouse gas emissions.
Overall, food purchases account for 16% of U.S. greenhouse gas emissions. (This compares with commercial and residential activity at 12% and industrial activity at 21%). Industries that produce beef, pork and other red meat generate the largest share of greenhouse gas emissions from household food purchases: about 21% of the total. Fresh vegetables and melons account for 11%, cheese industries about 10%, and milk products and butter about 7%.
The study also looked at the demographics of food-related greenhouse gas emissions. The highest levels of emissions were associated with white and highly-educated households. Households participating in the federal Supplemental Nutrition Assistance Program (SNAP) tended to be associated with low levels of greenhouse gas emissions when not accounting for any other household characteristics.
It is ironic that many of the opportunities for environmentally-friendly dietary changes are more available to the households that have the most resources, and yet such households tend to be the least environmentally responsible. As a result, changes in food consumption in these households could help reduce greenhouse gases by a disproportionate amount.
The study’s findings can inform the debate on which diets and food spending patterns can best mitigate greenhouse gas emissions from the food system.
Photo, posted April 9, 2009, courtesy of Janet Hudson Via Flickr.