The U.N. food agency says one-third of all food produced in the world gets wasted, amounting to a loss of $750 billion a year.
The Rome-based Food and Agricultural Organization said in a report Wednesday that food in developing countries is wasted mostly due to poor harvesting techniques, while in high-income areas the primary cause of waste is careless consumer behavior.
The report said food waste hurts the environment by causing unnecessary carbon emissions, extra water consumption and the reduction of biodiversity as farming takes over more land. The most serious areas of waste are of cereals in Asia and meat in wealthy regions and Latin America.
"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.
"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," he added.
Wastage of cereals in Asia is a significant problem, according to the report, 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.
FAO stressed the importance of raising awareness among consumers.
It says that consumers fail to plan their shopping, overpurchase, or over-react to "best-before-dates," while quality and aesthetic standards lead retailers to reject large amounts of perfectly edible food.
The Associated Press contributed to this report.