A UN report published this week reveals that 1.3 billion tonnes of food is being wasted worldwide each year, and that this is putting unnecessary strain on the natural resources humanity relies upon to feed itself.

The report, Food Wastage Footprint: Impacts on Natural Resources published by the Food and Agriculture Organisation (FAO) on Wednesday, examines the environmental consequences of the wasteful world food system, including its impacts on the climate, water and land use, and biodiversity. Overall, around a third of the food produced worldwide is wasted before it can be used.

Key findings from the FAO study include the revelations that production of food which is then wasted adds 3.3 billion tonnes of greenhouse gas emissions to the planet's atmosphere each year, and that wasted food also carries a water footprint of 250km³ (equivalent to the annual discharge of the river Volga).

Beyond its environmental impacts, the direct economic toll on producers of food waste (excluding fishing, which in the west is an infamously wasteful industry) is in the region of $750 billion annually.

"All of us – farmers and fishers; food processors and supermarkets; local and national governments; individual consumers – must make changes at every link of the human food chain to prevent food wastage from happening in the first place, and re-use or recycle it when we can't," said FAO Director-General José Graziano da Silva, responding to the report's findings. "We simply cannot allow one-third of all the food we produce to go to waste or be lost because of inappropriate practices, when 870 million people go hungry every day."

54 percent of the world's food wastage occurs "upstream" during production, post-harvest handling and storage, according to FAO's study. 46 percent of it happens "downstream," at the processing, distribution and consumption stages. In the Global North, where storage and infrastructure are generally more developed, most waste occurs as a result of the mores of consumerism, whereas in the South, waste occurs during or after production, before food reaches consumers or intermediate buyers.

However, although the general trends in food waste reveal certain patterns in distribution of waste, FAO notes that the impact of waste is less balanced than it would initially appear. Food wasted later along the food chain has a greater environmental footprint, as a result of the processing, transport, storage and cooking the food has undergone.

Amongst the reasons FAO gives for the food waste in the North are the quality and aesthetic standards retailers place on produce they buy, leading them to reject large amounts of perfectly edible food. Financial and structural limitations in harvesting techniques and storage and transport infrastructure, combined with climatic conditions that cause food to spoil quicker, lead to waste in the South.

FAO makes recommendations in bid to tackle waste

In a bid to encourage the changes FAO believes are needed to curtail food waste, the organisation has produced a 'tool kit' containing recommendations on how food loss and waste can be reduced at every stage of the food chain and profiling a number of projects around the world which have mounted successful bids to tackle wastage.

Achim Steiner, Executive Director of the UN Environment Programme (UNEP), said that FAO's recommendations, if implemented, could lead to widespread decarbonisation and meet the UN's goals on Zero Hunger.

The FAO recommendations include reducing food wastage in the first place (through balancing production and demand and avoiding the unsustainable use of natural resources to produce unneeded food), re-using within the human food chain (through donating surplus food to feed vulnerable members of society or using waste and surplus for livestock feed, conserving resources that would otherwise be used to produce commercial feedstuffs) and recycling and recovery of waste (scaling up by-product recycling, anaerobic digestion, compositing to recover energy in food and tackle dumping it in landfills, which is a major source of methane emissions.)

Hot spots

Several world food wastage "hot-spots" stand out in the study:

Wastage of cereals in Asia is a significant problem, with major impacts on carbon emissions and water and land use. Rice's profile is particularly noticeable, given its high methane emissions combined with a large level of wastage.

While meat wastage volumes in all world regions is comparatively low, the meat sector generates a substantial impact on the environment in terms of land occupation and carbon footprint, especially in high-income countries and Latin America, which in combination account for 80 percent of all meat wastage. Excluding Latin America, high-income regions are responsible for about 67 percent of all meat wastage

Fruit wastage contributes significantly to water waste in Asia, Latin America, and Europe, mainly as a result of extremely high wastage levels.

Similarly, large volumes of vegetable wastage in industrialized Asia, Europe, and South and South East Asia translates into a large carbon footprint for that sector.