They say there’s no such thing as a free lunch, but that’s about to change with the advent of food-sharing apps.

At least once per week — if not once per day — you probably have some leftovers, and you’re in good company. Many people have bigger eyes than their stomachs, and feel guilty about throwing away perfectly delicious meals. Composting helps assuage that guilt, but wouldn’t you rather give what you don’t need to someone who is in need of a nutritious meal?

In an era of app startups, it's not surprising that one leading app creator based out of Seattle, Washington — appropriately called LeftoverSwap — has heeded the call. You simply input what's up for grabs and the app instantly notifies others who have signed up as recipients. With most apps, givers and receivers live close to each other and agree on a safe place to meet.

An up-and-coming trend

"Some people are shocked and find the concept absolutely disgusting while others love it, and some wonder if it’s real,” says Dan Newman, co-founder of LeftoverSwap, which now has more than 10,000 users around the world. "There’s a large part of the population that want to do their best to share the resources we have," Newman says.

This "food sharing economy" blends frugality and sustainability, much like the home-sharing nature of Airbnb. And like Airbnb, people are still getting comfortable with this idea of sharing so openly.

It’s an honorable undertaking considering developed countries waste around 40 percent of food. In the U.K., households throw out 20 percent of all food purchased. Fortunately, the idea is catching on in places like Germany.

"Food waste has become a very hot topic here, and at the same time the sharing economy has boomed," Barbara Merhart, a coordinator for the German nonprofit, told the Guardian. "Personally, I don’t buy groceries anymore. Why would you spend money on it?"

A social phenomenon

While there are certainly users who are in high need of food and wouldn’t eat without food sharing, there’s also an increasing number of professionals who agree with Merhart and see no point in wasting money on groceries when there are so many leftovers. What started as a forum for sharing leftovers straight form the fridge has gotten the attention of shops, bakers and even high-end restaurants. Farmers are getting involved by donating extra goods to charities that are in need of food, via apps like Cropmobster.

Food sharing isn't just about charity; it's shifting into a social, community endeavor — and it's making a tangible difference. It’s estimated that 33 tons of food has been shared and saved so far. Clearly, "waste not, want not" is a mantra enjoying a much needed revival thanks to technology.

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