We've all heard the oft-cited statistic that 40 percent of food produced goes to waste, but what's in all that food? Until now, little has been known about what kinds and levels of nutrients all that wasted food contains.

That's why researchers at Johns Hopkins Bloomberg School of Public Health's Center for a Livable Future attempted to measure the cost of food waste at the retail and consumer levels in terms of the nutrients it could be providing to people. To do so, they tapped into two publicly available data sources—the USDA Food Availability and Loss-Adjusted Food Availability data sets—and performed a series of calculations to estimate the amount of nutrients lost through wasted food.

Here's what their new study, published in the Journal of the Academy of Nutrition and Dietetics, found: The food that's thrown away each day could provide 1,217 calories, 33 grams of protein, 5.9 grams of fiber, 1.7 mcg of vitamin D, 286 mg of calcium and 880 mg of potassium to each person in the U.S. each day.

"Wasted food in the United States contains a staggering amount of nutrients, especially nutrients that we tend to underconsume," said Marie Spiker, a doctoral candidate in the Bloomberg School's Department of International Health. Take fiber, for example—the recommended intake for an adult woman is 25 grams per day. "The amount of fiber that we're wasting each day as a nation is equal to that recommended intake for 74 million women," she said.

While not all food that is wasted can be recovered, the data provides a good reminder that we're dumping nutritious food that people who need it could be eating. "We should keep in mind that while food recovery efforts are valuable, food recovery doesn’t get to the heart of either the food insecurity problem or the waste problem," said Roni Neff, assistant professor in the Bloomberg School’s Department of Environmental Health and Engineering program. "We need strategies addressing these challenges at multiple levels.”

The researchers say these nutrient loss estimates could contribute to a baseline for measuring future progress.