People often say that you can’t improve what you can’t measure. This is very true when it comes to food loss and waste. Figures on how much food is lost or wasted and where in the supply chain they occur remain highly inconsistent. This is because some experts measure it in weight; others use calories, nutritional or economic costs. Governments aggregate data without considering deterioration in quality or drop in prices. And farmers tend to underestimate the losses.

The lack of data — and our subsequent lack of understanding of the magnitude of the issue — is not an excuse for the lack of action reducing food loss and waste. But it has been a major cause for inaction. Without knowing how much is lost where, we can’t know which interventions would be effective.

In 2011, FAO estimated that about one third of food produced globally is either lost or wasted. In 2013, it reported that if food waste were a country, it would be the third largest greenhouse gas emitter after China and the U.S., a narrative that has captured the popular imagination.

Today, my colleagues and I have released new estimates in The State of Food and Agriculture 2019. Based on data from governments and independent studies, we estimate that globally, around 14 percent of food produced is lost. Unlike the previous estimates that covered the entire supply chain, we zeroed in on three specific phases: from post-harvest to transport-storage-distribution to processing-and-packaging phases, which is right up to, but not including, the retail phase, where “food loss” becomes “food waste.”

Food waste, caused by consumer behavior, is more common in high-income countries. Food loss is more common in developing countries, and earlier in the supply chain, due to poor farming methods and inadequate infrastructure that can cause food to become degraded or spoiled.

We also consider, among other things, the economic values of different commodities, rather than simply counting the weight of lost products to help governments develop interventions. In the previous estimation, one ton of asparagus would have been equal to one ton of beef. But they are not the same, as the first carries nutritional cost, while the second has environmental cost.

The goal is to increase food and nutritional security and decrease environmental impact by reducing food loss and waste. Reductions at earlier stages of the supply chain — close to farm — are most effective in addressing food insecurity and stress on land and water. If the objective is to cut greenhouse gas emissions, reducing consumers’ food waste at the end of the supply chain is the best strategy, as it has more embedded emissions.

Despite the obvious benefits, cutting food loss and waste is not always a straightforward matter. For example, overproduction is one reason food waste happens, but it also prevents the risk of a food deficit. If governments enforced reduction of food loss and waste, it could actually backfire, increasing the price of food and lowering sales, which would hurt both suppliers and consumers. So governments need to make sure solutions are practical. They also need to get the private sector on board. More businesses – from tech start-ups that develop solar-powered cold storage to big food companies – are becoming interested in moving food efficiently.

A wide range of players across the supply chain have to work together to figure out potential solutions and put them into action. For example, better coordination between farmers and suppliers, could match supply and demand, preventing overproduction. It was this need to coordinate efforts that led the G20 agriculture ministers to request the launch of the Technical Platform on Measurement and Reduction of Food Loss and Waste in 2015.

Unfortunately, many countries deal with the growing demand for food by cranking up agricultural production, rather than cutting food loss and waste. This is much more expensive and environmentally damaging. Additionally, in low-income countries, the loss of marketable food means less income for farmers and pricier food for consumers, which has a huge impact on poor people. For example, the food loss in sub-Saharan Africa, where many smallholder farmers live on less than $2 a day, adds up to $4 billion annually.

Our analysis is far from perfect or complete. The most effective interventions require better data that’s not currently available. Economists, scientists and other food systems experts need to continue to improve methodologies to measure food loss and waste — eventually including pre-harvest losses, such as food that was not produced because of a lack of proper agricultural inputs and technology.

In our fight to end hunger and malnutrition, we have to balance the trade-offs. We must make sure everyone has access to sufficient and nutritious food, while ensuring environmental sustainability. Cutting food loss and waste is a potent weapon we have at our disposal in this fight.

(Photo credit: FAO/Jamaica via Creative Commons)