High food prices have contributed to a stubborn food-insecurity rate across the more than 3,100 counties in the U.S. during the last decade, a new report shows.

But exactly who is at risk of going hungry varies across the country.

"If we want to look at the health and well-being of America, one of the best ways to look at it is through food insecurity," says Craig Gundersen, lead researcher for hunger relief organization Feeding America's Map the Meal Gap project, which explores hunger and related trends in local communities.

According to the U.S. Department of Agriculture, some 40 million people in the U.S. were food-insecure in 2017, meaning they lacked consistent access to enough food for an active and healthy life. And although the national food-insecurity rate among individuals fell between 2016 and 2017 – from 12.9% to 12.5% – it remained above what it was before the Great Recession that began in 2007.

The latest annual Map the Meal Gap report, published Wednesday, shows the food-insecurity rate across U.S. counties was a similar 13.3% in 2017, down from 13.7% the year before. Rates ranged from a top mark of nearly 36% in Jefferson County, Mississippi , to just 3% in North Dakota's Steele County , yet researchers say no place is immune from the problem.

"Although we see pockets of high need across the country, like areas in the South and in rural parts of the country, the fact remains that individuals and families are at risk of hunger in every community," says Adam Dewey, a researcher with Feeding America.

For example, in Los Angeles County , an estimated 11% of people were food-insecure in 2017, but that amounts to roughly 1.1 million people, including more than 410,000 children, according to the report. Yet even communities with relatively few people in need – such as Schleicher County, Texas , where an estimated 260 people were food-insecure – can benefit from a more targeted focus on reducing hunger, researchers say.

The Implications for Health

Food insecurity has serious implications for health, the report notes. Among the 10% of counties with the highest estimated rates of food insecurity in 2017, 1 in 8 residents had diabetes , 1 in 3 were obese and 1 in 5 had some form of disability.

A separate analysis from the Centers for Disease Control and Prevention indicates that on average, food insecurity added about 11% to the health care costs of older adults in recent years – whether they had a chronic health condition or not.

"Food insecurity is a national health care crisis," says Gundersen, also a professor of agricultural and consumer economics at the University of Illinois at Urbana-Champaign .

Food-insecurity rates also are tied to higher unemployment and poverty: In 2017, two-thirds of counties with the highest food insecurity rates experienced "persistent poverty," where at least 20% of the population had lived in poverty for more than 30 years, the Feeding America research shows.

But the tie between health and food insecurity may be even closer than the link between health and income, homeownership or other financial challenges, Gundersen says: "Economic hardship is closely related to food insecurity, but (they) are not one and the same."

Many Who Need Help Don't Qualify for It

Roughly 60% of low-income households are food-secure, he says. Yet 29% of individuals estimated to be food-insecure likely do not qualify for federal aid through initiatives such as the Women, Infants and Children program or the Supplemental Nutrition Assistance Program.

Households that earn too much to qualify for SNAP can find themselves caught in a hunger gap, especially if they live in more expensive areas. Nationally, the average cost of a meal was $3.02 in 2017, for example, but counties in the Northeast saw an average meal cost of $3.32, while those in the West saw an average meal cost of $3.27, according to the report.

"Most counties with the highest meal costs (56%) are part of populous metropolitan areas," the report says. "While these urban counties with high meal costs tend to have lower rates of food insecurity, they are home to large numbers of people who are food insecure."

Adjusting for inflation, researchers estimated that the annual food budget shortfall for the nation's 40 million food insecure families reached nearly $21 billion in 2017.

SNAP Addresses the Problem

Expanding SNAP benefits to more people and addressing barriers to accessing the program – such as complex application and recertification processes – are key to reducing food insecurity in the U.S., Gundersen says. Those measures could be particularly important for food-insecure families living in wealthier areas because they also may not know they're eligible or face stigma for relying on federal aid.

"SNAP gives these low-income individuals the ability to go to food stores, purchase food that's correct for their families, and then engage in the civic culture of being able to shop at these stores alongside everybody else," Gundersen says.

Health care organizations also can leverage their partnerships with local food banks and other community groups to target food insecurity, Dewey says. Local food banks have hosted SNAP nutrition education programs to address diabetes and other health issues, while primary care providers can screen patients for food insecurity and refer them to Feeding America's services.