As stress on our food system increases, certain dietary patterns may increase harmful environmental impacts. Diets that are nutritious and sustainable, such as those low in animal products and higher in plant-based foods, have been proposed as a solution to this issue which still meets dietary needs. In this study, researchers analyzed 150 different dietary patterns from varying countries and regions by pairing an estimate of food demand with an estimate of commodity prices in different years, with consideration of any food-system and socioeconomic changes. Across the dietary patterns sampled, the most affordable and sustainable were vegan/vegetarian diets that replaced meat with legumes or whole grains. The least affordable were pescetarian diets that centered around fish, fruits, and vegetables. Staple crops, such as cassava, maize, plantains, potatoes, rice, soybeans, sweet potatoes, and wheat, tend to be the most affordable aspect of these dietary patterns. Household food waste accounted for 29% of all food costs, so helping people to reduce food waste could improve both affordability and environmental sustainability.
Lancet Planetary Health. 2021 Dec;5(12):e861. doi: 10.1016/S2542-5196(21)00316-8. Epub 2021 Nov 24. (Springmann M et al.)