ITHACA, NY. — More consumers buying plant-based alternatives instead of beef could reduce carbon dioxide emissions, but it also could lead to job losses in agriculture, according to a study appearing in the August issue of Lancet Planetary Health.

Researchers simulated three scenarios in which US consumers replace beef demand with plant-based alternatives at three different levels: 10%, 30% and 60%. The increase in purchases of meat protein alternatives could reduce the agricultural carbon footprint between 2.5% and 13.5%.

Forecasts for a reduction in greenhouse gas emissions were 7% for plant-based protein alternatives replacing 10% of beef demand, 20.9% for a 30% replacement and 41.4% for a 60% replacement.

“A reduced carbon footprint and increased food system resource-use efficiency are reasons alternative proteins could be in a portfolio of technologies and policies to promote more-sustainable food systems,” said Daniel Mason-D’Croz, PhD, lead author and a senior research associate at Cornell University in Ithaca. “Still, plant-based alternatives to beef are not silver bullets with their impact on other environmental dimensions of the food system — such as total water use — ambiguous.”

The number of cows needed for beef production could decrease by 2 million to 12 million. The cattle and beef processing sectors could decrease between 7% and 45%.

In the live cattle sector, employment forecasts were a 7.6% decrease for plant-protein alternatives replacing 10% of beef demand, a 22.5% decrease for a 30% replacement and a 44.1% decrease for a 60% replacement. The percentages for beef processing were an 8.1% decrease for 10%, a 24% decrease for 30% and a 47.1% decrease for 60%.

“In the aggregate, food system changes would have a small but potentially positive impact on national gross domestic product, but these changes would not be felt equally across the economy with substantial disruptions observed across the food system, particularly in the beef-value chain, which could contract substantially by as much as 45% under the 60%-replacement scenario — challenging the livelihoods of the more than 1.5 million people employed in these sectors,” Dr. Mason-D’Croz said.

A switch to plant-based protein alternatives from beef in the United States could increase beef exports to a range of 14% to 37% of the total beef category, which compares to the current 12%. New demand for crops could increase acreage for certain crops such as pulses that would be used in plant-based alternatives.

The study also involved researchers from Johns Hopkins University in Baltimore. The Stavros Niarchos Foundation, the Bill & Melinda Gates Foundation, Johns Hopkins University, the Commonwealth Scientific and Industrial Research Organisation, Cornell University, and Victoria University all funded the study.