What we eat has consequences. Our diets affect our health, the climate, land use and the future of those who make their living from it. A new international study published in the scientific journal Nature examines what could happen if the world radically changed the way it produces and consumes food.
According to its findings, a combination of healthier dietary choices, reduced food waste and improved agricultural production could cut carbon dioxide emissions associated with land use by as much as 85% by 2050. The research was conducted by scientists from the University of London, Cornell University in the United States and 10 other international research teams.
Lead author Dr. Matthew Gibson, a researcher at the London School of Hygiene & Tropical Medicine (LSHTM), explains the study’s broader implications to TO VIMA-Science.
An international model for healthy eating
The researchers based their study on a report by the EAT-Lancet Commission known as the “Planetary Health Diet.” The report was the product of a collaboration between the nonprofit organization EAT and the leading medical journal The Lancet, bringing together dozens of scientists specializing in nutrition, medicine, agriculture, environmental science and economics.
The report produced a series of dietary proposals and recommendations. While it does not advocate an entirely vegetarian diet or the complete elimination of animal products, it recommends reducing the consumption of red and processed meat and placing greater emphasis on plant-based foods such as vegetables, fruits, legumes, nuts and whole grains. It also includes smaller amounts of fish, poultry, eggs and dairy products.
As Gibson points out, the proposed dietary model was designed primarily with human health in mind, rather than as a diet conceived from the outset solely to promote sustainability.
The scenario scientists examined
Using this model as their starting point, the researchers employed advanced computer models to simulate possible future developments. They used 10 different global economic models examining how land use and food production interact with consumption, trade, prices and environmental impacts.
The scientists constructed a hypothetical scenario in which three changes occurred simultaneously: people adopted healthier diets based on the EAT-Lancet model, agriculture became more efficient through technology and food waste was cut in half.
The models incorporated historical data from the United Nations Food and Agriculture Organization from 1961 to 2020, along with projections for population growth, economic development, the climate crisis, crop yields, water and fertilizer use, and greenhouse gas emissions. Researchers then compared this alternative future with a business-as-usual scenario in which current dietary choices and policies remained essentially unchanged.
Less livestock, more crops
According to the scientists’ simulations, simultaneously changing diets, reducing food waste and improving agricultural production could create a global food system that requires less land to meet the world’s needs by 2050.
Total agricultural land use could fall by about 6% compared with 2020, largely because less land would be needed for livestock farming and animal feed production. At the same time, the economic value of cattle, sheep and goat production could decline by as much as 70% as consumption of animal products fell.
Conversely, a greater share of agricultural land could shift toward plant crops, which would take on a more central role in the global food system.
“We see a significant increase in the economic value of vegetable, fruit, nut and legume production, and a corresponding decline in the value of livestock production,” Gibson says. He stresses that such a shift would likely place significant pressure on livestock farmers, particularly in regions where animal production is a cornerstone of the local economy, making support and adaptation policies necessary.
The benefits for the environment and human health
The models also showed that greenhouse gas emissions associated with changes in land use could fall by as much as 85% by 2050, largely because there would be less need for deforestation and the expansion of agricultural land.
“Food systems are responsible for around 30% of global greenhouse gas emissions. Therefore, changing the way we produce and consume food can play an important role in addressing the climate crisis,” Gibson says.
As he explains, the scenario examined in the study could reduce direct annual emissions by around 1 billion metric tons of carbon dioxide equivalent (1 GtCO₂e), without including the additional benefits resulting from reduced deforestation.
At the same time, changing dietary patterns is not only about the environment. The global adoption of healthier eating habits could prevent millions of premature deaths each year.
“If the world continued along the path of current dietary and agricultural trends, we would continue to see millions of premature deaths related to diet, while the hidden costs of today’s food systems would continue to rise,” the researcher says.
As Gibson emphasizes, today’s food production systems carry substantial economic and environmental costs, placing pressure on ecosystems and contributing to the transgression of critical planetary boundaries. The major challenge will be transitioning to a more sustainable system without leaving behind the people and communities whose livelihoods depend on it.
