A new study turns up bad news.

Food Waste Energy
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If we're being honest, we've all let the occasional strawberry or banana go bad before we've had the chance to add them to our smoothies—or returned for a third serving of a dinner party's spread not because we're hungry, but because we can't resist the cheesy call of a delicious charcuterie plate. But that little bit of food waste is adding up big time. In fact, a new study shows we waste one-fifth of all our food.

Researchers at the University of Edinburgh have determined that the world eats 10 percent more food than it needs, while nine percent of fresh foods—meat, fruit, and vegetables—are tossed away or left to spoil before we've taken a bite. That breaks down to about 2.1 billion tons of harvested crops and 840 million tons of livestock wasted each year because of over-consumption, consumer waste, and inefficiencies in production processes, the researchers found.

But even if you're not disturbed by the 20-odd percent of food wasted each year, the consequences of such waste are downright sad, the study shows. If we could reduce our food waste, the researchers argue, we could improve what they call global food security, which ensures that everyone has access to a safe, affordable, and nutritious diet—with the added bonus of preventing future damage to our environment.

If we continue to demand the food we do now—and waste it at the same rate—we could make it very difficult to feed the world's growing population, the researchers warn. We'll also cause environmental harm by increasing greenhouse gas emissions, depleting water supplies, and losing biodiversity, they say.

Now that we've brought you down, there is a bit of good news: We can combat food waste and its very serious consequences. The researchers say making a difference is as simple as committing to eating fewer animal products and not eating more than we need to stay healthy. If we all do our parts, they say, we could even reverse these trends.