Are healthy dietary patterns aligned with sustainability?
Food systems have an evident role in both non communicable diseases and climate change. A transition toward food production and dietary patterns that have lower environmental impact and better health outcomes is therefore essential. Numerous studies are currently exploring how diet-related environmental impacts could be improved while considering nutritional quality, health, economic and social dimensions.
Three recent articles addressing the issue of aligning sustainability with its different dimensions are summarized in this month’s issue of the Global Fruit & Vegetables Newsletter.
The first article is a systematic review providing up-to-date evidence on the environmental impacts of adhering to a priori defined dietary patterns. According to this work, improving diet quality can reduce diet-related environmental impacts, although not in all cases. Additional research is needed to clarify how healthy diets with lower environmental impact are related to financial costs. While consuming organic foods resulted in higher costs, dietary patterns with higher environmental impact were also higher cost within the pre-defined set of nutritionally adequate dietary patterns.
The second article evaluated the environmental impact of five different U.S. dietary patterns, including the impacts of each food subgroup. Findings showed that omnivore dietary patterns have greater environmental impacts on land use, water use and GHG emissions than vegetarian and vegan diets. Red meat was the major contributor to all three environmental impacts in omnivore dietary patterns, with a much greater magnitude than the top contributors in vegetarian and vegan diets (dairy foods, nuts/seeds, and grains).
The third article assessed the nutritional quality and greenhouse gas emissions of vegetarian and non-vegetarian school meals served in primary schools in France. Findings showed that increasing the frequency of vegetarian meals, by serving egg-based, dairy-based or vegan recipes more frequently, would reduce greenhouse gas emissions while maintaining the nutritional quality of the meals served in primary schools.
These three articles highlight that healthy dietary patterns are generally more aligned with sustainability than less healthy dietary patterns, particularly those that consume red meat in excess. Strategies are needed to improve sustainability while also fostering economic and social inclusion.
Anna Herforth is a Senior Research Associate at Harvard T.H Chan School of Public Health, and a Visiting Senior Researcher at Wageningen University & Research. She holds a Ph.D. in International Nutrition from Cornell University, M.S. in Food Policy from Tufts University, and a B.S. in Plant Science from Cornell University. She is the Principal Investigator of the Global Diet Quality Project, and Co-Director of the Food Prices for Nutrition project. Dr Herforth is leading initiatives to improve measurement of food systems for healthy diets. She developed the Cost and Affordability of a Healthy Diet indicator that has recently been adopted by the UN FAO as a global food security indicator. She has worked in Africa, South Asia, and Latin America, including with agricultural and indigenous communities. Anna co-founded and co-leads the Agriculture-Nutrition Community of Practice (Ag2Nut), a professional community of over 9,000 members from 130 countries.