A survey of nearly 10,000 people by the department's Economic Research Service found 20 percent of the "improvements in diet quality" came from a reduction in consumption of food outside the home, the Los Angeles Times reported. The survey found, on average, Americans ate three fewer meals away from home and consumed 1 1/2 fewer snacks each month.
They consumed 127 fewer calories each day of the meals they did eat away from home, and said they wanted to be more knowledgeable about what they ate, the study said.
Forty-two percent of working-age adults and 57 percent of older adults said they used nutrition facts panel on food packages most or all of the time when deciding what foods to buy, the USDA said in a statement.
The study found the number of working-age adults who believe they are able to lose weight grew by 3 percent from 2007 to 2010, a period during which consumers increasingly relied on nutritional information, and not price, when shopping for food.
"When individuals believe that their actions directly affect their body weight, they might be more inclined to make healthier food choices," said Jessica Todd, author of the study.
The USDA credited several federal initiatives for the changes, including a website that offers meal planning advice and an online food tracking tool.