Toward a sustainable food system: Reducing food loss and waste
Reducing food loss and waste can contribute to food security and sustainability. Measuring food loss and waste, identifying where in the food system it occurs, and developing effective policies along the value chain are essential first steps toward addressing the problem. We need to set concrete targets at regional and country levels to reduce food loss and waste. For developed countries, the focus should be on waste; for developing countries, the focus in the short term should be on food loss, but also consider best practices for reducing waste in the longer term.
On the way from field to fork, substantial food loss and waste is common, posing a challenge to both food security and sustainability. Growing demand for food, stemming from both population growth and dietary changes associated with increasing wealth, is creating pressure on the world’s available land and scarce natural resources and contributing to greenhouse gas emissions. Food loss and waste compound this pressure. The overall productivity of our food system is reduced by food loss and waste, which can result in lower incomes for food producers and higher costs for food consumers. Much of the burden falls on the poor. Food loss and food waste have recently caught the attention of both researchers and policymakers, and sparked interest in initiatives to understand and reduce their impacts. As policymakers look to achieve the Sustainable Development Goals (SDGs) and the climate change commitments of 2015, reducing food loss and waste may provide an efficient means to improve food security and sustainability. Food loss and waste occur at different places along the food value chain: in production, postproduction procedures, processing, distribution, and consumption. Figure 1 shows the stages of the value chain at which food loss may occur, as well as the types of loss likely at each stage. These vary with different commodities and geographical locations. However, loss and waste are commonly the result of underlying inefficient, unjust, and unsustainable food systems. By reducing food loss and waste, we can improve food availability and food access—increasing the productivity of the food system without increasing agricultural inputs, the use of scarce natural resources, or the application of improved production technologies. However, success stories of reducing food waste and food loss are rare, and measurements of food loss and food waste remain highly inconsistent.
Food loss and waste have been defined in many ways, and disagreement remains over proper terminology. Although the terms “postharvest loss,” “food loss,” “food waste,” and “food loss and waste” are frequently used interchangeably, they do not refer consistently to the same aspects of the problem. Also, none of these classifications includes preharvest losses, such as crops lost to pests and diseases before harvest, crops left in the field, crops lost as a result of poor harvesting techniques or sharp price drops, or food that was not produced because of a lack of proper agricultural inputs and technology. To incorporate loss and waste along all stages of the value chain, from preharvest to table waste, we propose a more expansive definition using a new term: “potential food loss and waste” (PFLW), which includes these important preharvest losses and unrealized potential production.
Differences in definitions of food loss and food waste can affect the methodologies used to measure and interpret loss. Two estimation methodologies have been used to study food loss and waste. The macro approach, which uses aggregated data from national or local authorities and large companies, provides a low-cost way to measure overall food loss and waste along an entire value chain. The drawbacks to this approach include its lack of representative and good-quality data, particularly for low- and middle-income countries and for specific stages of the value chain, including primary production, processing, and retail. The micro approach uses data on specific actors at different value chain stages. These data are highly specific to region and context, and thus more useful for disentangling the origins of food loss and waste along the value chain and providing insights into potential prevention strategies. However, the micro approach is costly and time consuming to implement, and hampered by the inherent difficulty of collecting sufficient responses to represent an entire value chain or region. In addition, results from micro-level studies are often difficult to compare because the studies are adapted to specific objectives and stages of the value chain, and use different data collection and estimation methodologies. Neither the macro not the micro approach calculates PFLW—clearly presenting an area where measurement of food loss and waste needs improvement.