Swapping one beef serving for poultry per day cuts diet’s carbon footprint by almost half

14 Jan 2022 --- Consumers who eat beef could slash their diet’s carbon footprint as much as 48% by swapping just one serving of it per day for a more planet-friendly alternative – for example, choosing ground turkey instead of ground beef.

Researchers from Tulane University School of Public Health and Tropical Medicine and the University of Michigan came to this conclusion after examining data from a survey of what more than 16,000 US consumers eat in an average day.

The study looked at two metrics – daily diets’ greenhouse gas emissions and water scarcity footprint, a measure of the irrigated water used to produce the foods they eat. It takes into account regional variations in water scarcity.

Replacing a serving of shrimp with cod per day reduces greenhouse gas emissions by 34%.Beef was identified as the highest “impact item” and around 20% of survey respondents ate at least one serving of it in a day. If they collectively swapped one serving of beef, water-use impact declined by 30%, next to their lowered greenhouse gas emissions footprint.

“People can make a significant difference in their carbon footprint with very simple changes – and the easiest one would be to substitute poultry for beef,” says lead author Diego Rose, a professor of nutrition and food security at Tulane University’s School of Public Health and Tropical Medicine.

The new study’s findings are published in The American Journal of Clinical Nutrition.

Switching out shrimp and peanuts
Agricultural production accounts for about a quarter of global greenhouse gas emissions and about 70% of global freshwater withdrawals.

For the study, researchers built an extensive database of greenhouse gas emissions and water use related to the production of foods. They linked it to a large federal survey that asked people what they ate over 24 hours.

Although swapping beef had the greatest impact, they also measured the impact of changing other staple F&B items. Replacing a serving of shrimp with cod reduced greenhouse gas emissions by 34%; replacing dairy milk with soymilk resulted in an 8% reduction.

The most significant reduction in the water scarcity footprint came from replacing asparagus with peas, resulting in a 48% decrease. Substituting peanuts in place of almonds decreased the water scarcity footprint by 30%.

Wider impact beyond singular actions
“Shared Planet” currently leads Innova Market Insights’ Top Ten Trends for 2022, with the market researcher underscoring that consumers now rank planetary health as their number one concern, overtaking personal health, which has been the top priority in recent years.

Although individual substitutions were the focus of the study, Rose said that addressing climate change must involve more than singular actions.

The study also calculated the environmental impact if this change were implemented across all food consumption in the US in a day. If only the 20% of Americans who ate beef in a day switched to something else for one meal, that would reduce the overall carbon footprint of all US diets by 9.6% and reduce water-use impacts by 5.9%.

“The changes needed to address our climate problems are major. They are needed across all sectors and along all levels of human organization from international agencies to federal and state governments to communities and households,” Rose says.

“Many individuals feel strongly about this and wish to change our climate problem through direct actions that they can control. This, in turn, can change social norms about both the seriousness of the problem and the potential solutions that can address it. Our study provides evidence that even simple steps can assist in these efforts.”

Consumer discussions around the impact of food on carbon emissions are largely driven by the recent COP26 topics and trials of front-of-pack carbon labeling announced last year.

Edited by Benjamin Ferrer