Did the Great Recession make kids fat?

Growing up during the Great Recession of the late 2000s was rough for a lot of American kids: The only world they knew was a post-9/11 one, and the economic future looked grim.

Now, it turns out the hard times may also have long-term effects on their health, and their waistlines in particular.

Using data from the Bureau of Labor Statistics and the California Department of Education, researchers at the Johns Hopkins Bloomberg School of Public Health wanted to explore the relationship between unemployment in California during the Great Recession and the risk of the state’s public school students becoming overweight or obese.

Their study, published online this week in the Journal of Epidemiology and Community Health, uncovered a disturbing correlation: For every percentage point increase in county-level unemployment during the Great Recession, kids could expect a 14 percent increase in their body mass index, or BMI. Children in communities with higher unemployment were at a greater risk of obesity compared to those living in places where the economic conditions did not decline.

Here’s what that means in real terms: In 2008, 28 percent of the 1.7 million California students were considered overweight. By 2012, the prevalence increased to 37 percent. (The researchers looked specifically at children ages 7 to 18 who had height and weight measurements taken at two points in time, so they could track any changes.)

This is concerning, since children who are overweight have a greater risk of lifetime weight struggles and chronic diseases like diabetes.

This study is observational, so it can only show correlation rather than causation. The data was also only from California, which may not be representative of the rest of the country. But the researchers point out that obesity has long been correlated with socioeconomic status. And they speculated that hard economic times among families may have altered people’s eating habits.

When foods are ranked on a pure calorie per dollar basis, fats, sugar, grains, and potatoes are the least costly, while fruits and vegetables are the most expensive. (You can read more about eating on a budget here.)

“We think that unemployment — resulting in decreased income — could render fruits and vegetables and other more healthful foods unaffordable,” said Vanessa Oddo, a researcher in human nutrition at the Bloomberg School. “This would likely lead to increased consumption of cheaper, highly process convenience foods like boxed macaroni and cheese or fast food.”