By Megan Rowling / 6 June 2013

One of out every four calories produced by the world's farming system is being lost or wasted, setting back efforts to reduce hunger and provide enough food for a fast-growing global population, researchers said on Wednesday.

The world is projected to need about 60 percent more food calories in 2005 than in 2006, as its population tops 9 billion, but halving current rates of food loss and waste could reduce this gap by 22 percent, according to a study from the World Resources Institute (WRI) and the United Nations Environment Programme (UNEP). "Big inefficiencies suggest big savings opportunities," it said.

Wasting less food would lead to major savings in the use of water, energy, pesticides and fertilisers, and would be a boost for global food security, the study argued.

"Beyond all the environmental benefits, reducing food loss and waste will save money for people and companies,”said Craig Hanson, director of WRI’s people and ecosystems programme and a co-author of the study. "The world needs urgent solutions to feed its growing population, and reducing loss and waste is a critical piece toward a more sustainable food future."

Food loss refers to food that is spilled or spoiled after harvest and during transit, storage and packaging, while wasted food is food that is fit for human consumption but is thrown away before it can be eaten.

A previous estimate by the U.N. Food and Agriculture Organisation (FAO) calculated that 1.3 billion tonnes of food - around one third of all food based on weight - was lost or wasted in 2009. The new study converted this into calories intended for human consumption, and found that 24 percent was lost or wasted.

Regionally, about 56 percent of total food loss and waste occurs in the developed world, including China, and 44 percent in the developing world.

There is a difference in how it happens. More than half of lost and wasted food in Europe, the United States, Canada and Australia occurs close to the fork, at the consumption stage. But in developing countries, about two thirds occurs close to the farm, after harvest and storage.

Breaking down the food value chain globally, 24 percent of food loss and waste occurs at production, 24 percent during handling and storage, and 35 percent at consumption.

Water used to produce lost and wasted food each year equals 24 percent of all water used for agriculture, an amount that could fill 70 million Olympic-sized swimming pools, while the cropland used for wasted food is equivalent to the size of Mexico, the study said.

Separate analysis led by the FAO, to be published soon, indicates that if food loss and waste were a country, it would be the third highest emitter of greenhouse gases after the United States and China, the study added. Also, the inefficient use of fertiliser damages coastal zones and contributes to climate change, it said.

The researchers noted that in the 1970s  the world responded to an energy crisis caused by record high oil prices and soaring demand, by significantly improving its energy efficiency.

"Yet a 'war on waste' has yet to be waged when it comes to food. With food prices recently hitting historic highs and global food demand continuing to rise, now is the time,"the paper said.

SIMPLE SOLUTIONS

The study showcases simple, low-cost solutions for tackling food loss and waste that are already delivering environmental and economic benefits to communities around the world.

These include cutting portion sizes in the cafeterias of some U.S. universities by phasing out trays and introducing "pay by weight" schemes, and the use of sturdy plastic crates rather than sacks to transport fruit and vegetables in Sri Lanka and the Philippines.

In Afghanistan, an FAO project provided metal storage silos to 18,000 rural households, helping them cut crop losses dramatically. In Nigeria, the "zeer" - a system invented by a teacher that uses wet sand to cool food, without refrigeration - can keep produce fresh for up to 20 days and costs less than $2. 

"Everyone - from farmers and food companies to retailers, shipping lines, packagers, hotels, restaurants and households - has a role to play, and, in doing so, can contribute to maximizing the opportunities of the Millennium Development Goals, eradicating inequalities in rich and poor countries alike and laying the foundations of a more environmentally sustainable pathway for billions of people," said Achim Steiner, UNEP's executive director.

The study was released to coincide with World Environment Day, which is backing a campaign called "Think.Eat.Save - Reduce Your Foodprint", which encourages people to consume and produce food more sustainably.

In the run-up to June 5, internet users have submitted traditional food-saving ideas via UNEP's Facebook page. They include chuño from South America, which involves drying potatoes outdoors for five days, before trampling them to squeeze out any moisture. The finished product can last for months or even years.

UNEP also ran an online competition called Love Your Leftovers asking people to post recipes they use to clean out the fridge, which will be published in a book.

The study translates the amount of food wasted by households in rich countries into easily understood terms. Food waste at the consumption stage costs an average of $1,600 each year for a family of four in the United States, for example, and £680 (about $1,000) per household in Britain.

The problem is caused partly by confusing date codes on packaged food, the report said, with some big retailers like Tesco already working to simplify their systems so that consumers are less likely to throw away food that is still safe to eat.