It’s not surprising that food insecurity has a negative health and academic impact on young children — numerous studies have come to that conclusion. However, a new study has begun to dig a little deeper into the topic, zeroing in on the lingering aftermath of the Great Recession, when food insecurity and child poverty reached record levels, and examining the particular effects of transitioning from not worrying about having enough food to living in a household with limited or uncertain access to food.

Published this month in Health Affairs, the study looked at transitions in food security among kindergarteners and first-graders between 2011 and 2012 and its impact in three main areas: academics, health and behavior. Among the study’s many findings, the researchers found that children who transitioned from being food secure (defined as having access to sufficient food at an individual or household level) to being food insecure between 2011 and 2012 scored about 5 percent lower than their counterparts on assessments of verbal and nonverbal communication, self control, external behavior and internal behavior. Parents also reported worse health statuses for children who were persistently food insecure as well as for those who transitioned into food insecurity.

During the Great Recession, household food insecurity reached epidemic levels, increasing from 15.6 percent in 2006 to 21.3 percent in 2009. Child poverty in the U.S. reached a high of 22 percent in 2010.

The new food insecurity study is based on data on 6,300 U.S. children participating in the Early Childhood Longitudinal Study, Kindergarten Class of 2010-2011, which provides one of the first nationally representative pictures of child well-being after the Great Recession. Rachel Kimbro, co-author of the Health Affairs study and an associate professor of sociology at Rice University, told me that while the effects of food insecurity on kids have been studied before, it’s somewhat rare that a study endeavor can use the same cohort of children to examine a range of outcomes over a longer period of time. She said she expected to find that food-insecure kindergarteners and first-graders experienced the worst outcomes across all three domains. But surprisingly, she found that kids who were food secure in kindergarten, but transitioned into food insecurity by first grade, experienced the worst impacts, especially in behavioral outcomes.

Kimbro and study co-author Justin Denney write:

Our dynamic approach to understanding food insecurity provides unique insights into behavioral problems. Whereas previous research has found broad associations between food insecurity and behavioral problems, our results suggest that the timing and duration of food insecurity are key. Children transitioning into food insecurity display more externalizing behavioral problems, while children in chronic states of food insecurity display more internalizing behavioral problems. These findings reveal that the transition into food insecurity may be a stressful and frightening experience that can change the way children engage with the world.

Among the study cohort, Kimbro and Denney found that 80 percent of children were food secure at both kindergarten and first grade, while 7 percent transitioned from being food insecure to being food secure and 6 percent transitioned in the opposite direction. Overall, 14 percent of children were living in food-insecure households in kindergarten and 13 percent were food insecure in first grade. In general, teachers reported worse scores for interpersonal skills, self-control, internalizing behaviors (for example, suppressing feelings and having anxiety) and externalizing behaviors (e.g. breaking rules or being physically aggressive) among food-insecure children. When compared to children who were food secure in kindergarten and first grade, children who transitioned from food security to food insecurity had significantly worse ratings on interpersonal skills, self-control and externalizing behaviors. For internalizing behaviors, there was only a significant difference between children who were persistently food insecure and those who were not.

The researchers also found that parents in food-insecure households assigned worse ratings to their children’s overall health than parents who hadn’t experienced food insecurity during the study period. When taking into account a variety of confounding variables, the study did not find a significant association between food insecurity transitions and academic outcomes among first-graders. (It’s good to note here that while a link between food insecurity transitions and poor academic outcomes wasn’t uncovered, the study did find that children who were food insecure in kindergarten and/or first grade did have lower academic scores in reading, math and science when compared to kids who were food secure during the study period.) Kimbro said of this finding: “If you think of the outcomes in terms of proximity to food insecurity, it makes more sense that we’d see an impact more quickly on behavior rather than academic achievement.”

Kimbro and Denney conclude:

Although we found no significant associations between food insecurity and academic outcomes, we did find consistent increased behavioral problems and worse reported overall health status — results that are troubling. More dynamic approaches to studying food insecurity are needed, which demonstrates the vital importance of longitudinal and comprehensive data. Furthermore, food insecurity is not just another issue that poor families face. Instead, it is a fundamental and multidimensional obstacle to the healthy development of children.

Obviously, the study’s findings have a number of policy implications. Among them, Kimbro said they demonstrate that our current food assistance programs and policies aren’t responding as quickly as they should for families in crisis — “our policies just aren’t nimble enough when helping families in this situation,” she noted. In addition, she said the findings could help both health care providers and schools better identify the signs of food insecurity and take action. Such work can be incredibly important, as numerous studies have found that children who are food insecure early in their academic careers may be more likely to eventually drop out of school as well as develop adverse mental and physical health problems, Kimbro noted.

“For schools, they’re really on the front lines,” she told me. “If they could identify kids in crisis and be able to head it off at the ground level, that could make a big difference.”

Kimbro said that she and her colleagues intend to follow the same group of children through the fifth grade to examine their trajectories over time and gain a better understanding of the long-term impacts of food insecurity. As for food assistance programs, congressional budget battles continue to threaten their ability to help those in need.

While the number of Americans who struggle to afford food has declined in recent years, more than 48 million Americans lived in households that struggled with hunger in 2014.

“Thinking about food insecurity as a genuine public health issue is really important,” Kimbro said. “It’s not just a poverty issue. It’s a health issue.”

To request a full copy of the food insecurity study, visit Health Affairs.

Kim Krisberg is a freelance public health writer living in Austin, Texas, and has been writing about public health for more than a decade.