WUR: Revision of dietary guidelines necessary

Dietary guidelines issued by national governments aim to set a roadmap for healthy living. But a new international study published in Lancet Planetary Health 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.

The study by researchers at Wageningen, Cornell and Zürich universities and the Research Institute of Organic Agriculture FiBL uses principles of circular food production systems to assess environmental consequences and nutritional contributions of national food-based dietary guidelines. The authors show 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. At the same time, the quantity at which most nutrients were provided on a "circular diet" were comparable to the dietary guideline's recommendations.

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 full 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.”

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