Nearly 40 per cent of food in the United States ends up in the trash, according to an analysis by the Natural Resources Defense Council.

That amounts to $165 billion of uneaten rations each year and nearly 20 pounds of wasted food per person every month.

In its report on food waste, the environmental advocacy group says that the U.S. food system is inefficient with food being tossed at almost every link in the supply chain, from production and packaging to restaurants and households. The average American wastes 10 times as much food as someone in Southeast Asia.

American families throw out approximately 25 per cent of their groceries, a loss of $1,365 to $2,275 every year for a family of four.

People who frequent restaurants aren’t any less wasteful. On average, diners leave 17 per cent of their meals uneaten and 55 per cent of these potential leftovers are not taken home.

According to the U.S. Department of Agriculture, American households, restaurants and caterers altogether discarded 126 billion pounds of food in 2008 alone. Grocery stores threw away 43 billion pounds of food, mostly unsold fruits and vegetables.

The excess is taking a toll on the environment, the report says. In addition to wasted resources during production, rotting food makes up the single largest component of landfills across the U.S.

The report encourages consumers to reduce waste by not overbuying at the grocery store, understanding expiration dates and eating their leftovers.