In a recent article published in the journal Nature Food, researchers developed a global database that can provide consequential insights into the locations, composition, magnitude, and environmental footprint of food loss and waste (FLW). Their work can be an important tool for policymakers to make global food supply chains (FSCs) more sustainable and secure.
Study: Global food loss and waste estimates show increasing nutritional and environmental pressures. Image Credit: ArieStudio / Shutterstock
Background
Transitioning to a more sustainable and secure food system requires drastic reductions in FLW globally. Not only does food wastage from FSCs imperil efforts to achieve universal food security and eliminate hunger, but it also leads to natural resource depletion, contributes to climate change, and threatens economic stability.
To meaningfully address the issue of FLW, policymakers require accurate estimates of the locations, composition, and magnitude of wastage to identify where interventions can provide the greatest environmental and socioeconomic benefits. However, there is a lack of consistent FLW estimates resulting from a dearth of comprehensive approaches. Multidisciplinary frameworks are required to formulate policy responses. Single-country assessments have also not been undertaken on a large scale.
About the study
Researchers collected the most reliable estimates of discarded and lost foods from several commodity groups, geographical regions, and stages of food supply. Their definition of FLW included inedible parts and pre-harvest losses but excluded seeds and material converted to animal feed, bio-based products, or other material uses.
They used the database to trace nutrition and food supply across different FSC stages and create an input-output framework at the global level. The additional analysis included country-level FLW trends from 2004 to 2014 and factored in the effects of international trade. Environmental footprints of FLW generation were calculated by integrating data on greenhouse gas (GHG) emissions and land and water use.
Findings
The results indicate that 1.92 gigatons of food were wasted in 2014, a rise of 24% over 2004 levels. Traded food accounted for nearly 16% of global food waste. The manufacturing stage was the most significant contributor to this drastic increase as processed food consumption rose worldwide.
However, agricultural cultivation, including post-harvest management, accounted for nearly half of global FLW (956 megatons). In terms of plant-based waste, sugarcane and sugar beet cultivation were major contributors.
Together, India, China, and North America (particularly the United States) accounted for 43% of global food waste. However, in terms of per capita FLW, high-income countries such as Hong Kong, Singapore, New Zealand, and Australia were the largest contributors, while India and China contributed far less FLW per person.
An important difference between high-income and low-income countries was which FSC stages were most wasteful – in low-income countries, there were more losses during early stages, such as during handling and storage post-harvest. In contrast, high-income countries waste more during the final stages, such as consumption.
Decomposition analysis suggests that rising food demand accounts for 96% of the increase in FLW between 2004 and 2014. Greece, Italy, and Japan have successfully reduced FLW by addressing this driver, while Germany and Mexico were able to do so by modifying the composition of their food.
As FLW rises, so does the magnitude of nutritional losses, including calories, proteins, and carbohydrates. The study estimates that 775 calories on average are lost per person every day, rising to 1,560 calories per capita in high-income regions due to the consumption of high levels of sugars, processed foods, and animal-sourced foods. Sub-Saharan Africa showed the lowest amount of calorie and protein losses.
The environmental footprint estimates suggested that nearly one-fifth of agricultural lands and water in the world were used to produce food that was wasted or lost; Latin America, Southeast Asia, and the Caribbean islands accounted for the majority of the land, while Southeast Asia, Oceania, and North America contributed the largest amount of water. The carbon footprint of wasted food in 2014 was 1.8 gigatons of CO2, with sub-Saharan Africa, Southeast Asia, Oceania, and North America contributing the largest share of emissions.
Conclusions
As the global population grew and wealth increased, FLW led to rises in environmental and nutritional pressures. Alarmingly, this research estimated that between one-third and one-fourth of all food produced for the consumption of humans was wasted or lost. The researchers validated their findings and cross-referenced them with regional and country-level estimates where available.
The authors acknowledged certain limitations based on the lack of high-quality granular data, particularly in the final stages of FSC and in low- and middle-income countries. Further research can build on these findings to conduct multidisciplinary investigations that will promote strategies to build a more sustainable and less wasteful global food system.
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