Replacing half of all animal-based foods in the U.S. diet with plant-based alternatives could reduce climate-altering greenhouse gas emissions by 1.6 billion metric tons by 2030, according to a study by researchers at the University of Michigan (UM) and Tulane University.
The study, posted on the UM’s website on Thursday, found that replacing half of all animal-based foods, such as red meat, poultry, seafood, eggs, dairy and animal-based fats, with plant-based alternatives would reduce U.S. diet-related emissions by 35 percent. Based on U.S. Census Bureau population projections, that would amount to a savings of 224 million metric tons per year in 2030.
A reduction of 224 million metric tons is equivalent to the annual emissions of 47.5 million passenger vehicles and represents 24 percent of the reduction needed for the United States to meet targets under the Paris climate agreement, according to the study.
The target of a 50-percent reduction in animal-based foods assumes that the dietary shift would occur gradually between now and 2030, resulting in an estimated cumulative emissions reduction of 1.6 billion metric tons.
And if, in addition to cutting animal-based foods by half, U.S. consumers also reduced beef consumption by 90 percent, the emissions savings would be even greater, according to the study. Dietary emissions would be cut by 51 percent before a cumulative reduction of 2.4 billion metric tons of greenhouse gas emissions by 2030 could be realized.
In the absence of dietary change, emissions associated with producing the food we eat are expected to increase 9 percent by 2030 due to population growth, said Martin Heller, lead author of the study and a research specialist at UM’s Center for Sustainable Systems at the School for Environment and Sustainability.
“While a diet shift isn’t a silver bullet, it could play an important role in curbing climate change,” he said.
Diet-related greenhouse gas emissions include carbon dioxide, methane and nitrous oxide, and are expressed in the study as carbon dioxide equivalents.
The Intergovernmental Panel on Climate Change said in its 2019 report that reducing greenhouse gas emissions from food production is a key to solving the climate crisis. Keeping global temperatures at safe levels will require significant changes to the way the world produces food and manages land as well as consumer behavior, according to the UN intergovernmental body.