All minimize combined environmental costs (as described shortly and in the Methods section) while satisfying 44 nutritional constraints, but each comprises a distinct randomly chosen subset of available plant items (a randomization based solution strategy often called Monte Carlo, hereafter MC).Īs in our earlier work cited above, here “replacing” means exact replacement of the protein content of the forgone meat (i.e., protein is an equality constraint) while satisfying 43 additional inequality constraints of both signs that collectively ensure the plant replacement diets are at least as nutritious as the meat they replace. We thus employ linear programming to devise hundreds of plant based partial diets that replace beef alone or its sum with pork and poultry, the dominant U.S. diet with plant alternatives in a nutritionally rigorous manner have been only preliminarily explored. Yet while beef is by far the most resource intensive 12, 13, 14 poultry and pork also use more resource than most plant alternatives 15, 16, and replacing them is likely to further improve the environmental performance of food systems 17.ĭespite the above expectations, the nutritional and environmental consequences of replacing all meat in the mean U.S. We have also identified the primary reason for these losses, large land use disparities between animal based products and their nutritionally equivalent plant based alternatives 13, and quantified the resource use and nutritional outcomes expected from a nutritionally sound, protein equivalent plant replacements of beef in the U.S. food system and the potential environmental and food security benefits of eliminating these losses 12, 13, 14. We have recently quantified the generalized losses associated with feed-to-food conversion in the U.S. Plant-based alternatives to meat are thus potentially desirable 7, provided they can be rigorously shown to quantitatively enjoy nutritional and environmental consequences that are at least benign, but preferably beneficial 8, 9, 10, 11. While livestock production contributes disproportionally to these impacts both per kilocalorie (kcal) and per gram (g) protein 3, 4, 5, producing plant based items for direct human consumption is less resource intensive 6. While widely replacing meat with plants is logistically and culturally challenging, few competing options offer comparable multidimensional resource use reduction.Īgriculture is among the key ways humans impact 1-mostly adversely 2-natural environments. By replacing meat with the devised plant alternatives-dominated by tofu, soybeans, peanuts, and lentils-Americans can collectively eliminate pastureland use while saving 35–50% of their diet related needs for cropland, Nr, and GHG emission, but increase their diet related irrigation needs by 15%. We develop a new methodology for identifying nutritional constraints whose satisfaction by plant eaters is challenging, disproportionately shaping the optimal diets, singling out energy, mass, monounsaturated fatty acids, vitamins B 3,6,12 and D, choline, zinc, and selenium. We show that protein conserving plant alternatives to meat that rigorously satisfy key nutritional constraints while minimizing cropland, nitrogen fertilizer (Nr) and water use and greenhouse gas (GHG) emissions exist, and could improve public health.
Because meat is more resource intensive than vegetal protein sources, replacing it with efficient plant alternatives is potentially desirable, provided these alternatives prove nutritionally sound.