Environmental footprint of vegetal and animal based foods in relation to the nutritional requirements of the human body

Food production accounts for a significant fraction of the environmental footprint, which is, in turn, affected by diet patterns (vegetarian vs. animal vs. mixed). The relationships between the food-associated environmental footprint and nutritional parameters are poorly known. Methods: We selected common vegetal and animal foods, both alone and combined, and calculated food quantities needed to satisfy the Recommended Daily Allowances (RDAs) of the Essential Amino Acid (EAA). These quantities were then ranked for land use, Green-House-Gas-Emission [GHGE], water footprint [WF], weight, calorie, protein, sodium and saturated fat content. A global environmental/nutritional score was developed for each food or combination, and the scores were ranked. Results: Although some vegetal foods appeared more advantageous over animal ones for their GHGE and water footprint (maize, soybean), sodium and saturated fat content (pea, soybean, maize, rice, bean), others were instead associated to greater land use (pea and bean), food weight (potato and cauliflowers), protein (wheat, bean, maize, cauliflower, peas, rice), and calories (wheat, maize, rice, potatoes) than animal ones. The global score of pure vegetal foods were not consistently better than those of the animal or mixed foods. The ten foods with the worse global scores included seven vegetal vs three animal ones. Conclusion: Vegetal foods are not necessarily advantageous over animal ones from an EAA- perspective; this can be explained, from an environmental & nutritional standpoint, by extensive land use, limited protein quality, and high energy intake.