(CBS News) Many of us end up throwing out food we think is past its prime - a habit that provides Food For Thought according to Tracy Smith:
There are no hard-and-fast rules for food expiration dating. Most people don't want to take chances, so once food hits the printed expiration date, they simply toss it out.
But tossing it out has become a problem in itself. It's been estimated that up to 40 percent of food produced in the U.S. goes right in the trash.
"I can be as picky as everybody else," says Janet Kalish, and she can afford to be. She's no vagrant - Kalish is a New York City high school teacher who got fed up with seeing supermarkets toss out good food. So for the past eight years she's been doing her shopping on the streets.
She told Smith, "I would say about 90 percent of what I eat is 'rescued food'" - food that comes from the garbage.
And she doesn't need to look very hard. She showed Smith a "pretty close to a perfect eggplant," and loaves of bread still warm.
Even in a down economy, food is apparently still cheap and plentiful enough to waste. According to a recent estimate, Americans throw out $165 billion worth of food every year. That's about 20 pounds per person every month.
And then there's the food that doesn't even make it to stores or homes: At farms across the country, tons of perfectly good produce is routinely plowed under.
"There are a number of reasons why crops are left in the field," said Christy Porter, who runs Hidden Harvest in California's Coachella Valley. "But most of the time the farmer is a victim of his or her own success. Sometimes they grow too much, and sometimes it's just too big for the box."
Porter's workers pick through harvested fields to salvage what's left over, before the plows catch up with them.
"Many times we've eaten dirt behind the plow to get the produce harvested," Porter said.
The rescued produce goes straight to local communities, like a retirement home, where they wait in line for food that otherwise would have gone to waste.
And this is really small potatoes, so to speak, compared to this: At Loaves and Fishes in Naperville, Ill., 75 percent of everything there was destined for the dumpster. Now it's free, for the needy.
Linda Dore is a grateful client. "This is a good alternative to not eating," she said.