Cornellians lead Lancet special issue on improving planetary diets

The statistics are sobering: one in ten people worldwide are at risk of hunger while 2 billion people are overweight or obese, roughly one-third of all food produced is wasted, and agriculture contributes about one-third of global greenhouse gases. Transforming our food systems to be more healthy, sustainable and just will require thoughtful, multi-pronged approaches that value human and planetary health. That's one of the key messages in a special issue of The Lancet Planetary Health, published Nov. 3, and coordinated by five members of Cornell's Food Systems and Global Change (FSGC) group, led by Mario Herrero, professor of global development in the College of Agriculture and Life Sciences (CALS) and Cornell Atkinson Scholar.

"This special issue is a significant contribution to the body of work on how to transform the food system for people and planet," Herrero said. "It showcases that we need to implement multiple actions simultaneously to ensure that we maximise the synergies between environmental protection, human health and just food systems."

The special issue stems from the work of the EAT-Lancet Commission - a group of global experts from more than 35 countries and six continents - which released its second report Oct. 3. In preparing that report, the FSGC group realized there was far more information they wanted to provide than could fit in the report, so began developing the special issue, said Daniel Mason-D'Croz, senior research associate in the Department of Global Development in CALS.

Earth's planetary boundaries are already under tremendous strain as a result of climate change, land use pressures, and biodiversity loss. Food systems sit at the intersection of all those crises, Mason-D'Croz said.

"The food system is a bit like a water balloon: if you push down on one part of it, something else comes up," he said. "This is a real struggle with food system transformation, because we want to reduce emissions, but we also want to reduce land use and reduce water use. We want people to have affordable access to healthy diets, but we also want to pay the people who produce our food a decent wage. That's why we really can't address these issues in isolation, we need multiple, intersecting, bundled solutions that can address these systems holistically."

For example, shifting to healthy diets aligned with the EAT-Lancet recommendations can have health and environmental co-benefits; however increased consumption of fresh fruits and vegetables may lead to greater food loss and waste, since fresh produce are more perishable than less-healthy processed foods, said Marina Sundiang, who led one of the papers of the special issue and is a postdoctoral associate in FSGC. Measures to reduce and manage food loss and waste are integral to counterbalancing this rebound effect and transforming food systems, she said. For example, consumers might need to shop for smaller amounts more frequently, communities may need to increase access to composting facilities, and governments should invest in research to help growers and producers develop better storage practices and healthier processed options.

Throughout the special issue, researchers considered potential solutions for producers, consumers and governments to improve food systems. For consumers, a key recommendation was adoption of a healthy diet composed of modest consumption of animal-sourced foods, and increased consumption of fruits and vegetables. For producers, recommendations included increasing productivity and increasing circularity - or recycling of nutrients - throughout the food supply chain (for example, by more careful management of fertilizers). For governments, sustained, long-term support of scientific research and development is key in developing new varieties and management practices that can feed more people with fewer resources.

Thais Diniz Oliveira, formerly a postdoctoral associate in FSGC and now a sustainable development specialist with the United Nations Development Programme, and Matthew Gibson, postdoctoral associate in FSGC, also contributed to the special issue. The first EAT-Lancet report was published in 2019, just after Gibson started his Ph.D. program in environmental policy, and the report transformed his thinking about the interconnectedness of social and ecological systems. He hopes this second report and special issue will be similarly eye-opening for others.

"My hope for the special issue would be to catalyze new collaborations across food systems research and policy," he said. "We've brought together 10-12 state-of-the-art food system models, a hundred researchers across the world, but there are still so many questions we need to answer. Not least of all, how to transform systems at the speed and scale required. Because there's a lot to do, and not much time to do it."

Key contributors from other institutions include: Wageningen University in The Netherlands; Potsdam Institute for Climate Impact Research in Germany; University College London; the University of Purdue, Indiana; and the International Food Policy Research Institute in Washington, D.C.

This research was funded by the Cornell Atkinson Center for Sustainability, the Bill and Melinda Gates Foundation, the CGIAR Foresight Initiative, as well as donors who supported the individual modeling teams that contributed to these studies.

Krisy Gashler is a writer for the Cornell Atkinson Center for Sustainability.