The lack of reliable food sources plague large portions of our world - while at the same time, those that have food available to them waste more than half of it.

Hard data is still being collected, but experts at the Reuters Food and Agriculture Summit in Chicago this week said an estimated 30 percent to 50 percent of the food produced in the world goes uneaten.

In a year, that means each person throws away almost 400 pounds of food, the weight of an adult male gorilla.

Not only is this wasting food, it's also expensive.

The average American throws away 33 pounds of food each month -- about $40 worth -- according to the Natural Resources Defense Council, which plans to publish a report on food waste in April.

Global experts worry that the problem of waste is bigger and about more than just food and money;  They say that this carefree attitude towards the available food source affects other elements of our survival.

Agriculture is the world's largest user of water, a big consumer of energy and chemicals and major emitter of greenhouse gases during production, distribution and landfill decay.

Experts say reducing waste is a simple way to cut stress on the environment while easing pressure on farmers, who will be called on to feed an expected 9 billion people around the world in 2050, versus nearly 7 billion today.

"No matter how sustainable the farming is, if the food's not getting eaten, it's not sustainable and it's not a good use of our resources," Dana Gunders, a sustainable agriculture specialist at the NRDC, said at the Reuters Summit.