Editor's note: Rachel Smith is the co-founder of Halfsies, a social initiative offering a choice to restaurant-goers that provides a healthier meal portion, reduces food waste and supports the fight against hunger. Follow Halfsies on Twitter.

We're all familiar with the phrase "waste not, want not," but how well are we applying these words today?

For many of us, we buy more than we need, we spend more than we earn, we eat more than our fill. The consequence of excessive living and waste affect not only us, but also our global neighbors and future generations.

Over the past two decades, food waste and obesity have nearly doubled at equal rates. The surface area of the average dinner plate expanded by 36 percent between 1960 and 2007. Parallel to increased portion sizes, between 1987 and 2010, the number of Americans diagnosed with diabetes almost tripled to 20.9 million.

While we are responsible for our own choices, the results we are experiencing aren't merely a matter of choice. We are not genetically programmed to turn down excess calories when they are in front of us. Studies have shown that if our plate contains more food than our body physically needs, we will eat it without conscious consideration.

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