Study recommends cutting meat, milk, going plant-based

Chef grilled pork ribs. [iSockphoto]

Replacing 50 per cent of meat and milk products with plant-based alternatives by 2050 can reduce agriculture and land use-related greenhouse gas (GHG) emissions by 31 per cent and halt the degradation of forest and natural land, according to new research.

According to the study just published in Nature Communications, additional climate and biodiversity benefits could accrue from reforesting land spared from livestock production when meat and milk products are substituted by plant-based alternatives, more than doubling the climate benefits and halving future declines of ecosystem integrity by 2050.

The restored area could contribute up to 25 per cent of the estimated global land restoration needs under Target 2 of the Kunming Montreal Global Biodiversity Framework by 2030.

"We'll need much more than 'Meatless Mondays' to reduce the global GHG emissions driving climate change - and this study shows us a path forward," said study co-author Eva Wollenberg of the University of Vermont (UVM). "Plant-based meats are not just a novel food product, but a critical opportunity for achieving food security and climate goals while also achieving health and biodiversity objectives worldwide. Such transitions are challenging and require a range of technological innovations and policy interventions."

The study, by researchers at UVM, the International Institute for Applied Systems Analysis (IIASA), the Alliance of Bioversity International, and CIAT, is the first to look at the global food security and environmental impacts of plant-based meat and milk consumption at large scales that considers the complexity of food systems.

"Understanding the impacts of dietary shifts expands our options for reducing GHG emissions," said study lead author Marta Kozicka, a researcher from IIASA. "Shifting diets could also yield huge improvements for biodiversity."

The authors found that a 50 per cent substitution scenario would substantially reduce the mounting impacts of food systems on the natural environment by 2050.

Findings indicate global agricultural area declined by 12 per cent instead of expanding. The decline in areas of forest and other natural land is almost completely halted. Water use declines by 10 per cent instead of increasing.

The authors developed scenarios of dietary changes based on plant-based recipes for beef, pork, chicken, and milk. These recipes were designed to be nutritionally equivalent to the original animal-derived protein products and realistic for the existing food manufacturing capabilities and globally available production ingredients.

To ensure relevance and as a potential user of the findings, the research team solicited input from Impossible Foods, a company that develops plant-based substitutes for meat products. The company provided generic recipes for the plant-based meat substitute products used in the analysis. The science team had complete control over decision-making for this peer-reviewed study, and the data are not specific to Impossible Foods.

The full environmental benefit of diet shifts can be achieved if the agricultural land spared from livestock and feed production is restored through biodiversity-minded afforestation. In the 50 per cent scenario, the benefits from reduced land-use emissions could double as compared to a scenario without afforestation.

"While the analysed dietary shifts serve as a powerful enabler for reaching climate and biodiversity goals, they must be accompanied by targeted production side policies to deliver their full potential. Otherwise, these benefits will be partly lost due to production extensification and resulting GHG and land-use efficiency losses," explains IIASA Biodiversity and Natural Resources Program Director Petr Havlik.

While the results support the increased use of plant-based meat substitutes, the authors recognize that livestock are a valuable source of income and nourishment for smallholders in low- and middle-income countries, and have significant cultural roles, reduce risk, and diversify smallholder income.

Simultaneously, climate change threatens the livelihoods of smallholder farmers. Rapid policy and management action to avoid environmental risk and support farmers and other livestock value chain actors for a socially just and sustainable food system transition will therefore be crucial. This is particularly important considering recent setbacks in achieving food security globally.