U.S. consumers waste almost a pound of food per person each day, with 30 million acres of cropland used to produce this food every year – an area equivalent to 7.7% of all harvested cropland in the US or half the size of the UK. The most wasted foods are actually the healthiest, namely fruits and vegetables. This is the finding of a new study published in the journal PLOS ONE. To investigate the link between food waste, environmental impact and diet quality, researchers collected data on food intake and diet quality from the 2015 Healthy Eating Index and USDA’s What We Eat in America database, and combined it with available food waste data. They calculated the amount of cropland used to produce uneaten food using a biophysical simulation modelling. They found that between 2007 and 2014, U.S. consumers wasted nearly 150,000 tons of food daily – or 422 grams per person. “This accounts for 30% of daily calories available for consumption or one-quarter of daily food (by weight) available for consumption,” the authors write in the journal. To produce this wasted food, 30 million acres of land (121,405 square kilometres) are used annually.

In addition, the researchers and estimated the amount of agricultural inputs required to grow the food that was ultimately wasted by consumers. Nearly 4.2 trillion gallons (15.8 trillion litres) of irrigation water were used, with the majority of wasted irrigation water used to produce fruits (1.3 trillion gallons) and vegetables (1.05 trillion gallons). Farmers also used 780 million pounds of pesticides and 1.8 billion pounds of nitrogen fertiliser each year in order to produce food that is eventually thrown away. According to the authors, higher quality diets were associated with higher levels of food waste. Fruits and vegetables and mixed fruit and vegetable dishes accounted for 39% of food waste, followed by dairy (17%), meat and mixed meat dishes (14%), and grains and grain mixed dishes (12%). Foods and dishes considered less healthy, such as candy, soft drinks and salty snacks, caused a smaller amount of food waste. “Higher quality diets have greater amounts of fruits and vegetables, which are being wasted in greater quantities than other food,” said co-author Meredith Niles, a University of Vermont assistant professor. “Eating healthy is important, and brings many benefits, but as we pursue these diets, we must think much more consciously about food waste.” The study also found that healthier diets used less cropland than lower quality diets.

“Consumers face a delicate balance between following dietary recommendations to increase their consumption of fruits and vegetables (which requires purchasing more of them) while also wasting less of them,” the authors write. The researchers argue that increasing consumers’ knowledge about how to prepare and store fruits and vegetables will be one of the practical solutions to reducing food waste. Consumers need more education on how to tell when fruits and vegetables are ripe, how to store and prepare them, and how to tell the difference between bruises/abrasions and spoilage. Niles highlights efforts to reduce food waste, including French grocer Intermarché’s “inglorious fruits and vegetables” campaign, which promotes the cooking of “the disfigured eggplant,” “the ugly carrot,” and other healthy, but otherwise superficially damaged produce. Increased efforts to plan food purchases based on household food stocks is one way consumers can reduce waste due to over-purchasing. Policy efforts are needed to revise sell-by dates and labels to reduce consumer confusion. “Food waste is an issue that plays out at many different levels,” said lead author Zach Conrad from the Grand Forks Human Nutrition Research Center. “Looking at them holistically will become increasingly important to finding sustainable ways of meeting the needs of a growing world population.” (ab)