John Floros, dean of the College of Agriculture at Kansas State University, said U.S. households, supermarkets, restaurants, other food-service providers throw away about 4 out of every 10 pounds of food produced each year.
The waste includes food uneaten and spoiled in refrigerators and on pantry shelves, as well as food that people throw away after cooking.
Scientists say food waste in landfills releases methane gas as it decomposes. Methane is about 20 times more potent than carbon dioxide as a greenhouse gas that fosters global warming, Floros said.
Reducing food waste would contribute to solving great global challenges providing more food to a growing population, reducing greenhouse gases and reducing the amount of freshwater needed to grow crops, Floros said.
The middle class in China is consuming almost three times as much meat compared with a few decades ago. Demand for convenience foods also is rising with the growth of the urban population.
Floros said in a statement not enough is being done to resolve food issues to adequately feed the world's population into the future.
"Consumers, industry, universities and governments all need to pitch in," he said. "The first step is more awareness of these issues and the need for action on multiple levels of society."
Floros presented his findings at the 245th National Meeting & Exposition of the American Chemical Society in New Orleans.