Identifying Optimally Sustainable Foods: A Four-Dimensional Analysis of Sustainable Foods in the American Diet

A holistic understanding of food sustainability is vital for making socially and environmentally conscious food choices. Sustainable diets have been defined by four dimensions: health, economics, environment, and society. The purpose of this study was to determine how metrics for nutritional quality, monetary cost, environmental impact, and social and cultural acceptability of foods and beverages vary across and within food groups and to identify which foods and beverages are optimally sustainable according to these metrics. Data from the Food and Nutrient Database for Dietary Studies (FNDDS) was linked with frequency of consumption, nutrient density, environmental impact, and cost data from publicly available databases. A sustainability index, based on the four dimensions, was developed to quantify overall sustainability. Nutrient density was correlated negatively with environmental impact and frequency of consumption but positively with cost ( p < 0.001). Out of 5964 items, 165 were identified as optimally sustainable. Sustainability index scores varied within each food group. Less than 1% of optimally sustainable items were Dairy products, while 62% were Protein Foods—of which 92% were Plant Proteins. Few foods and beverages met the criteria to be considered optimally sustainable. However, Plant Protein foods may generally strike the best balance among these four indicators of sustainability. A holistic understanding of food sustainability is necessary to facilitate nutritious and environmentally conscious dietary choices that adhere to other needs, personal values, and preferences.