It was the third year in a row that the department has seen an increase in the number of households experiencing hunger and those worried about having enough money to pay for food.
Based on a Census Bureau survey of 50,000 households, the department estimated that 3.8 million families were hungry last year to the point where someone in the household skipped meals because they couldn't afford them. That's an 8.6 percent increase from 2001, when 3.5 million families were hungry, and a 13 percent increase from 2000.
Also, more and more families are unsure if they can afford to eat or don't have enough food in their cupboards.
Last year, 11 percent of 108 million families were in that situation. That's up 5 percent from 2001 and 8 percent from 2000.
Most poor families struggling with hunger tried to ensure their children are fed, the report said. Nonetheless, one or more children in an estimated 265,000 families on occasion missed meals last year because the families either couldn't afford to eat or didn't have enough food at home.
Margaret Andrews, a department economist and an author of the annual survey, said the prevalence of hunger and food insecurity is clearly tied to the poverty rate because they fluctuate together.
The survey "was a confirmation that the series of data over the years are behaving as you might expect, in a similar manner that poverty is," she said, noting the latest estimates by the Census Bureau show more people are poor.
Some 34.6 million Americans were living in poverty last year — 1.7 million more than in 2001, according to the Census Bureau.
It doesn't seem as if hunger would be a problem in this country since food is abundant. Supermarket shelves in the United States are filled with hundreds of different products and restaurants are practically on every corner.
Plus, the country is struggling with fat. Nearly 65 percent of adults and 13 percent of children are overweight, according to the Centers for Disease Control and Prevention.
Barbara Laraia, an associate professor of nutrition at the University of North Carolina-Chapel Hill, said hunger and obesity can coexist because many hungry families struggle with their weight. She said they tend to buy high-calorie foods that are low in nutrients.
"They're dependent on foods that are going to make their bellies feel full, rather than on nutrients," Laraia said. "The diet is compromised."
Also, many families will spend their incomes on fixed expenses before buying food.
"Food is the most elastic part of the budget, meaning that's what households will compromise on when they have fixed payments such as their rent and their utilities," Laraia said.
Jim Weill, an advocate and president of the Food Research and Action Center, said more families are hungry because they still are reeling from the 2001 recession. He also blamed a minimum wage that hasn't been raised from $5.15 an hour since 1997.
The Agriculture Department said surveys since 1995 show that low-income households most likely to suffer from hunger are Hispanic and black, single-mother families, and those in inner cities and southern and western states.