Imagine the global food trade as a river that flows between nations. Think of it not only as a flow of goods between nations, but a flow of inputs—nations trading the water, land, and labor it takes to produce food for trade. Like an actual river, those foods flow between resource-rich and resource-poor states. And like actual rivers that carry water between nations, the trade of food products can be contentious, politically and economically strategic, and a source of conflict when resources become scarce—motivation, certainly, to provide a growing world with an abundant, equitable supply of food.
When we talk about feeding 9 billion people by 2050, we talk about greater efficiencies in agriculture, greater outputs, and greater yields. But greater efficiency means more than farm productivity: it means reducing food waste, too.
Food is wasted across the production chain: crops are lost in the fields, grains rot in storage, perishables spoil in transport, grocers reject damaged and cosmetically imperfect foods, and consumers throw away food they just don’t eat. And the story here isn’t as simple as table scraps left in the trash—the way food is wasted is hugely unequal across continents, and what we waste is far more than just the food that’s left uneaten.
The first thing to understand when tackling the scale of food waste is to understand how waste happens differently between countries. In the United States, as in other high-income countries, the primary driver of food waste is consumer waste and taste. Consumer waste happens at the household level, when consumers overbuy or overcook and throw leftovers or spoiled groceries away uneaten. And consumer taste, arguably the more significant source of waste, is the driving force behind grocers’ stocking selections: consumers, and by extension grocery stores, demand perfect, unblemished foods—meaning any foods that don’t meet visual standards never make it to supermarket shelves. True, some of this food is salvaged: some is donated to food banks, some is recycled into animal feed or compost. Despite those efforts to ameliorate waste, the US still discards 141 trillion calories annually—that’s 31 percent of US food production.
In low- and middle-income countries, the picture is different. Here, the bulk of food waste is not due to consumer waste, but rather gross inefficiencies in the production, storage, and transportation of foods. Here, improper storage can result in the spoilage and rot of crops and grains, and shipping problems due to gaps in the cold chain or excessive time spent in transit on inadequate infrastructure can cause food to spoil before ever reaching a consumer. And this distinction is key: in high-income countries, waste happens on the consumer end, after the farmers have been paid. In low- and middle-income countries, these losses happen in farmers’ fields and storage facilities; the cost of these losses falls onto the farmers themselves.
Overall, how much food is wasted worldwide? The UN Food and Agricultural Organization estimates that one third of global food is wasted, but where and how food is wasted varies. Globally, 20 percent of all meat is wasted, but in sub-Saharan Africa, it’s closer to 30 percent, the majority of which happens at the production level—which equates to direct profit loss to farmers. Fruits and vegetables: 45 percent is wasted globally. In both sub-Saharan Africa and North America, more than 50 percent of fruits and vegetables are wasted—however in North America nearly all of that loss is consumer-driven, whereas in sub-Saharan Africa, the largest contributor to loss is processing; again, lost profit to farmers.
Worst of all, when you waste food, you’re not just wasting what you don’t eat. You waste the inputs that made that food: the land that had to be cleared to farm, the time and labor of farmers, and the fossil fuels used to plant, fertilize, harvest, and transport that food. By current estimates, the land under plow producing nothing but food waste is approximately the size of China; the greenhouse gases emitted to produce that wasted food are greater than those emitted by any country except China and the United States; and worst of all, when you waste food, you waste the water used to grow it.
Fresh water is less than 3 percent of all water on earth. Most fresh water, moreover, is inaccessible to people: only 1.3 percent of freshwater is in rivers, lakes, ice, or snow. And this little fresh water we can access isn’t distributed evenly, and how it’s distributed is rapidly changing along with the climate. In 2015, the UN estimated that global demand for water would increase 55 percent by 2030. Taken together—water scarcity, climate change, unequal distributions of water, increasing demand—an estimated 700,000,000 people will be displaced by 2030 from their land because water will become too scarce to support them there.
This is the real issue: we’re throwing away water when we waste food, exacerbating scarcity.
A single head of broccoli takes almost six gallons of water to produce. The typical American may drink up to a gallon of water a day, but eats up to 1,300 gallons of water every day via the water footprint of one day’s food. And that’s just at the per-person level. The water footprint of food and agriculture products traded internationally amounts to a type of “hidden trade balance”—a country that imports food is also, by extension, importing water. Taking imported food’s water footprint into account, 76 percent of the water flow between countries does so as traded food and agricultural products.
At a human level, as water resources are squeezed, the price of those foods that require the most water to produce will rise. Fruits and vegetables and meats—water intensive and perishable—will be impacted the most. These are also the most nutritious foods. In low- and middle-income countries, in the near future, the issue of hunger—abject, caloric hunger—will likely be solved sooner than later. But the hidden hunger of nutrition deficiencies will only worsen as greater scarcity for water drives the price of high-nutrition foods out of the reach of those who need those nutrients most.
Ultimately, food waste is an enormous problem, but it’s not unsolvable. The key to its solution, however, is metrics: we can’t solve what we can’t measure, and when it comes to food waste, there’s endless room to improve how we measure. Currently, on-the-ground metrics for food waste in low- and middle-income countries are estimates and models at best, but that can soon change. With the rapid proliferation of mobile technology in those regions, the opportunities to crowdsource real-time metrics through apps and handheld devices are booming: soon, remoteness of farmers, or smallness of processors, or complexity of supply chains will no longer be the inhibitor to data collection they currently are. What’s more, programs are underway to harmonize metrics across countries, and solutions-based approaches to capture those resources intrinsic in food waste are proliferating and becoming increasingly profitable.
This is the big picture that’s really at play when we talk about food waste. When we throw away food, we’re not just tossing the scraps from our plate: we’re throwing away the land that was cleared to grow it, the labor of farmers, and most of all, water—a global resource of increasing value and scarcity—exacerbating hidden hunger, and further straining water stressed agricultural zones. It’s a problem, and an opportunity, presenting solutions and an undeniable urgency. How do you think we can best approach this complex problem of waste? Tell us your thoughts and continue the conversation @GlobalAgDev.