The Environmental Protection Agency estimates that every day, 1.5 pounds of food per person is thrown away in the United States. The most immediate cost is to the individual, but as with all waste, the ramifications fan out like a stack of falling dominoes.

Wasted food wastes labor and resources, including water. Production to replace it adds to society's cost. Then there's the cost of trucking it to landfills, where it decomposes and releases methane, a greenhouse gas more potent than carbon dioxide. Food left in trash containers increases the rodent population, the mitigation of which bears its own cost.

The holidays: Every year, there's an uptick in food waste between Thanksgiving and the new year. In a recent op-ed piece in The Wall Street Journal, Anna Lappe and Danielle Nierenberg wrote that Americans waste about 5 million tons of food during the holiday stretch -- "enough to fill 125,000 18-wheelers."

This byproduct of affluence has troubling moral implications in a world where hunger is staggering, and it is perpetuated on farms and in households, grocery stores and restaurants.

Of the food Americans spend time preparing, 25 percent is thrown out, about 96 billion pounds each year, according to the U.S. Department of Agriculture.


Affluence isn't the main reason globally. Ms. Nierenberg, who has worked internationally with farmers toward a more sustainable agriculture, said much Third World food waste is attributable to lack of adequate storage and the challenges of getting food to markets.

The United Nations Food and Agriculture Organization reports that 1.3 billion tons of food that's wasted internationally could feed the estimated 868 million people who need it.

"Food waste has been on the international discussion table for a long time," Ms. Nierenberg said. "The first World Food Conference in 1974 called for a 50 percent reduction in food waste through the subsequent decade. That was not achieved."

In Pittsburgh, several organizations have been assertive in food rescue.

The Greater Pittsburgh Community Food Bank, whose spokesmen could not be reached for comment, has worked with restaurants, hotels, caterers and other institutions to distribute unused food to shelters, soup kitchens and after-school programs. It is also the region's leading distributor of donated food, much of it from grocers.

Springboard Kitchens rescues 7,000-10,000 pounds of fresh food that otherwise would have been thrown away every month. Its job-training clients work with professional chefs to prepare 4,000 meals, including to clients of Meals on Wheels.

The area's largest grocery retailer, Giant Eagle, reports progress in cutting waste and diverting "approximately 6 million pounds of food to local food banks each year," spokesman Dick Roberts said. "Regarding food waste at Giant Eagle, we work closely with our supply partners and store teams to limit waste as much as possible. While as a private company we cannot share specific details, we continue to see reductions in food waste on a yearly basis."

Trader Joe's stores have donation coordinators who arrange for the use of food it can't sell.

At the store in the East Liberty neighborhood of Pittsburgh, that's Patrick Staub's role.

"Everything we can't sell that's edible we donate to the food bank," he said. "If they can't pick it up, we give to local food kitchens and churches."

He said the percentage of food that ends up as waste at the store fluctuates.

Produce:The least donated and most wasted items are produce, and not just because they are perishable. People who do not farm or grow gardens are likely to reject buying a blemished apple or a misshapen carrot."

We want our food to look a certain way," said Jonathan Bloom, author of the 2010 book "American Wasteland."

"If it's the wrong shape or has a blemish of any kind, it still tastes good but it'll be cast aside somewhere along the food chain. A lot of supermarkets are reluctant to donate [produce], even though they are protected by the Good Samaritan Act," he said.

The Good Samaritan Food Donation Act of 1996 protects from liability donors who give in good faith to nonprofit organizations.

The greatest waste is on the farm -- food not harvested for reasons of cost, weather, pests or unappealing retail characteristics, Mr. Bloom said. Households collectively are the second biggest source of waste."

As food prices keep going up," he said, "the one silver lining is that it might force us to take better care of the food we have."

Despite rising prices, the percentage of household spending on food is 10 percent, lower than any other country, he said, citing statistics from the Bureau of Labor Statistics. "And that's near all-time lows. We don't tend to value things we don't spend much on."

Jena Roberts, a vice president for business development with the National Food Lab in Livermore, Calif., said some food waste results from misinterpretation of use-by and sell-by dates.

"People are taking those dates as holy grails and they're not," she said. "If it's a shelf staple product, those dates don't raise safety issues.

You could lose a little bit of taste or freshness, so it's more of a food quality issue." The smell test is usually reliable, though she added, "If it's a refrigerated product, I would pay more attention to the dates."

The government doesn't require freshness dates except on infant formula; they are stamped by manufacturing companies to note the last date of optimum quality. Grocers honor those dates by throwing out perfectly good food before they pass.

The "Freegan" movement of Dumpster divers has emerged to take advantage of this surplus, its credo being to never take more than you need.

Jeremy Seifert's short film "Dive!" shows scavengers collecting bright bananas, packages of steak, apples, cucumbers, partial cartons of eggs and other groceries from trash bins. "Rescuing food is great," the narrator says, "but why is all this food not being given to people who need it? We're feeding our landfills more than we're feeding our country."

Restaurants: While grocers have their own challenges, the EPA reports that about 15 percent of all food waste in landfills comes from restaurants.

Most of it is food the diners don't finish, Mr. Bloom said. "That food is paid for, so restaurants haven't felt the financial pinch." But there should be an ethical and environmental pinch, he said. "There is no reason to serve as much food as we do."

"There has to be a system in place to make it easy for a restaurant" to reduce waste, either through composting or a redistribution network, Ms. Nierenberg said. "Until they pay their workers more to make the extra effort, it's not going to be easy."

The National Restaurant Association has been working with grocery manufacturers and the Food Marketing Institute to decrease food waste in restaurants, grocery stores and manufacturing plants, said Sue Hensley, an association spokeswoman.

"We're making a concerted effort to push our ConServe program to operators" to help them order more accurately and quantify their waste. "We are working with the U.S. Composting Council in trying to allow for more food composting. We've seen some successes, including Atlanta's zero-waste zones, where some operators have decreased waste by 70 to 80 percent."

Mr. Bloom said he wishes the USDA would devise a plan to measure waste in each step of the food chain. "Then it would be possible to know how much we can reduce waste," he said.

He became interested in the issue during a master's degree research project at the University of North Carolina.

"This topic really grabbed me as a way to think about how we as a country approach food. I saw a real problem and a real opportunity. I don't think it would be too difficult to dramatically reduce our waste."