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By Matt Hayes
  • Department of Global Development
  • Food
Dietary guidelines issued by national governments aim to set a roadmap for healthy living. But a new study challenges national dietary guidelines assessments to include the environmental impact of food production, with implications for how dietary guidelines account not just for the health of the human population, but also the planet.

Research published in the June 2022 issue of Lancet Planetary Health uses principles of circular food production systems to assess environmental consequences and nutritional contributions of national food-based dietary guidelines. The study by researchers at Cornell, Wageningen, and Zürich universities and the Research Institute of Organic Agriculture FiBL shows that the amount of animal products recommended by national nutritional guidelines in Europe could be substantially lowered in favor of more plant-based food, and that major environmental consequences of food choices could be addressed through improved agricultural practices.

The findings

While some countries such as Germany and Sweden do currently account for environmental sustainability in their nutritional guidance to citizens, for most nations, food-based dietary guidelines are designed strictly around human health and nutrition. The study explored five European countries — Bulgaria, Malta, the Netherlands, Sweden and Switzerland — with different geographies and cultural habits. The researchers found that reductions in the recommended amount of animal products in diets had the potential to reduce greenhouse gas emissions in most cases. Additionally, the use of circularity principles in agriculture would allow for improved land use. The study found that Sweden and the Netherlands could reduce greenhouse gas emissions by 12% and 24% and reduce land use by 22% and 24%, respectively.

Why it matters

Environmental impacts must be critical considerations when devising national dietary guidelines, according to the study authors. Circular food production systems, which emphasize closed nutrient cycles, are essential to producing food on less land and with reduced environmental impacts.

The authors suggest that for the full environmental impact to be realized, a complete transformation of the food system is necessary. The changes include substantial reductions in total animal numbers and animal products, investing in livestock breeds that are better suited to low-opportunity-cost biomass, and a shift in the amount of mineral fertilizers and livestock feed imports.

According to the authors, “Only by consistent transformations of food systems in this regard can the estimated environmental improvements be reached.”

What the experts say

“Policymakers need to take a wide view that incorporates environmental sustainability when setting national guidelines. This study provides further evidence that circular food production systems are a promising solution to achieve sustainable healthy diets."

  • Mario Herrero, professor of sustainable food systems and global change in the Department of Global Development at Cornell’s College of Agriculture and Life Sciences and Cornell Atkinson Scholar

“In view of current and future challenges such as climate change, it becomes inevitable that dietary recommendations consider environmental sustainability, within boundaries for healthy eating. This is especially important for animal products, where recommendations should be revised and recommended quantities lowered."

  • Anita Frehner, lead author and research scientist of the Research Institute of Organic Agriculture in Switzerland

“Right now, the dietary recommendations that people base their food choices on give a distorted view of the planetary impact of what they eat. National dietary recommendations haven’t kept pace with the changing climate, and it’s critical that governments reassess what it means to eat healthy.”

  • Hannah van Zanten, senior author, associate professor at Wageningen University and a visiting professor at Cornell’s Department of Global Development
Study authors

Anita Frehner, Renée P M Cardinaals, Imke J M de Boer, Adrian Muller, Christian Schader, Benjamin van Selm, Ollie van Hal, Giulia Pestoni, Sabine Rohrmann, Mario Herrero, Hannah H E van Zanten


The research was funded by the Swiss National Science Foundation and the Dutch Research Council.

Read the full study

“The compatibility of circularity and national dietary recommendations for animal products in five European countries: a modelling analysis on nutritional feasibility, climate impact, and land use”


Matt Hayes is director for communications for Global Development in the College of Agriculture and Life Sciences.

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