A county-by-county breakdown shows Northern Virginia and the Maryland suburbs of D.C. are generally much healthier than the national average.

The 2024 County Health Rankings & Roadmaps, produced by the University of Wisconsin Population Health Institute, looks at why there are differences in health within and across communities.

Dr. David Goodfriend, Loudoun County’s health director, says the study allows counties to track their own progress, and see how they compare with similar counties nearby and across the country.

The study looks at health outcomes and health factors, which generally play a role in a person’s overall health.

“For health outcomes, some of the key measures are life expectancy, premature deaths — to what extent are people dying before we would expect them to, at the end of their life span. Also how was their mental health and physical health during that time being studied.”

For health factors, 9% of Loudoun County adult residents are obese, below the Virginia average of 13% and the national average of 15%.

“We know that tobacco use is more likely to cause premature death, and it looks at alcohol use,” Goodfriend said of the study.

The study also looks at the physical environment, including air pollution and drinking water violations.

“It looks at driving times, because the longer someone’s on the road, the less likely they’re able to exercise, and the more likely they are to be in a car accident,” said Goodfriend.

Wealthier counties tend to have healthier residents, according to the study.

“Insured individuals tend to live longer than uninsured individuals, because they can catch diseases earlier,” said Goodfriend. “Having easy access to health care providers and mental health providers tend to factor into health outcomes as well.”

Even for a wealthy county, such as Loudoun County, Goodfriend said the study is valuable in pointing to disparities.

“In Loudoun County, if you’re an Asian-American, on average, you’re going to live 10 years longer than if you’re a Black American in Loudoun County,” said Goodfriend. “If you’re a child in Loudoun County, you’re twice as likely to die if you’re Black or Hispanic, than if you’re Asian and white.”

Goodfriend said studies like this one are a first step toward improving health outcomes for all county residents.

“We see these disparities. In different data sets we can see disparities on where within the jurisdiction people live,” said Goodfriend. That allows local governments, health departments, and schools to focus what can be done to make all county residents as healthy as possible.

“Are there areas where people don’t have access to quality food? Or to exercise? And how do we invest in those areas,” said Goodfriend.