Global food systems: addressing malnutrition through sustainable system pathways

Abstract

Addressing malnutrition (in all its forms) whilst developing a global food system compatible with environmental sustainability remains one of the most pressing challenges of the 21st century. The current framing of our food systems fails to fully capture the inequities in production, distribution, efficiency and sufficiency of all components necessary to end malnutrition. This research presents a holistic, scalable and replicable framework to model food system pathways (across all essential nutritional components, including macronutrients, micronutrients and amino acids), providing quantification of production, losses, allocation and conversions at all stages of the value chain. Furthermore, this framework attempts to translate current food metrics—often presented in tonnage or absolute terms—into daily per capita figures to provide important context for how this translates into food security and nutrition. This framework can be applied at global, regional and national levels. Here, this model is first presented at a global level and then focuses on India as a national-level example. Results highlight that, at a global level, we produce the equivalent of 5800 kilocalories and 170 grams of protein per person per day through crops alone. However, major system inefficiencies mean that less than half of crop calories and protein are delivered (or converted) for final food supply. Pathway inefficiencies are even more acute for micronutrients; more than 60% of all essential micronutrients assessed in this study are lost between production and consumer-available phases of the food supply system. Globally we find very large inequalities in per capita levels of food production, ranging from 19,000 kilocalories (729 grams of protein) per person per day in North America to 3300 kilocalories (80 grams of protein) in Africa. Large variations are also seen in terms of food system efficiency, ranging from 15-20% in North America to 80-90% in Africa. Understanding regional inefficiencies, inequalities and trade imbalances will be crucial to meet the needs of a growing global population. This case is exemplified in India-specific framework results. India’s domestic production capacity would result in severe malnutrition across a large proportion (>60%) of the population (even under ambitious yield and waste reduction scenarios) in 2030/50. This shortfall will have to be addressed through optimised intervention and trade developments. This work also explores a number of solutions which couple improved nutritional outcomes with sustainability. Analyses of global and national nutritional guidelines conclude that most are incompatible with climate targets; the recommended USA or Australian diet provides minimal emissions savings relative to the business-as-usual diet in 2050. Low-cost, high-quality protein will remain a crucial element in developing an effective and sustainable food system. This research explores the potential of two sources. Results find that meat substitute products have significant health and emission benefits, but are strongly sensitive to both price and consumer acceptability. The environmental impact of aquaculture is strongly species-dependent. This study provides the first quantification of global greenhouse gas emissions from aquaculture, estimated to be 227±61 MtCO2e (approximately 3-4% of total livestock emissions). This is projected to increase to 365±99MtCO2e by 2030.