Regional food preferences influence environmental impacts of diets

Dietary changes, mainly in developing countries, will be the major driver for an increase in environmental impacts of the global food system. Many assessments of these impacts have used the food patterns of high-income countries as the reference. However, it is questionable whether people in very different socioeconomic, cultural, and biophysical contexts will adopt the food pattern of Western Europe or North America. This paper explores the environmental implications of regional differences in diets around the world. Changes in dietary composition between 1961 and 2018 were reviewed. Comparable regional diets were envisaged by adjusting existing local food preferences to a daily consumption of 3,500 kcal/cap/day, of which 30% of the calories were considered to be from animal products. Our results show that the compositions of regional diets remained relatively stable from 1961 to 2018, particularly in consumption of animal products, and are not approaching homogeneity across regions. If future diets retain their present composition, the environmental impact may be up to 30% lower than the typical “low estimate” of an affluent diet from the literature (e.g., the Mediterranean diet), but in some cases higher than the “top estimate” of an affluent diet in the literature (e.g., the North American diet); driven mainly by the type of meat consumed. Diets differ in the relative magnitudes of their effects on individual environmental indicators. For example, one diet may cause less water use but more greenhouse gas emissions than another diet, so different strategies are required for the reduction of their environmental impacts. We conclude that pathways to reduce environmental impacts of the global food system should be designed in the context of regional differences in food consumption.