Eating disorder behaviors, including binge eating, present significant threats to the health and functioning of many Americans. Many individuals across the nation struggle with sleep disturbances, which also hurts their health.

Leah Irish, North Dakota State University associate professor of psychology, is examining sleep disturbances' impact on binge eating. She received an award from the National Institute of Health for her research entitled “Investigating 24-Hour Patterns of Sleep and Negative Affect Among Individuals with Recurrent Eating Behavior,” which will further study the relationship between the two. Kristine Steffen, NDSU professor of pharmaceutical sciences, is the co-principal investigator on the study. The award is part of a $3.2 million partnership with Sanford Health.

 “My research focuses on the interaction between sleep and other everyday waking behaviors,” Irish commented. “In recent years, I have begun a collaboration with Sanford Research to study how sleep impacts binge eating behavior, which is the most common form of disordered eating and can lead to serious medical and psychological consequences.”

“This grant is exciting because it allows me to advance this line of research to investigate sleep and binge eating on a more granular, day-to-day scale,” Irish added. “We are incorporating new constructs into our research model, including napping, sleepiness, and behavioral timing, to understand better how sleep and binge eating may influence one another daily. In addition, I view the receipt of this funding as an acknowledgment of NIH’s recognition of the importance of this work and appreciation for its potential impact.”

Irish earned her Ph.D. in experimental health psychology from Kent State (Ohio) in 2011 and has been at NDSU since 2013. She has always been interested in psychology and decided to focus on sleep as something every person does and what most like to do. Her work has focused on everyday sleep problems because they occur more often but are often more challenging to address.

“This prestigious NIH award to Dr. Irish is not only a tribute to her expertise in the biomedical sciences and her unique focus on sleep disorders and binge eating, but it also highlights NDSU’s prominence nationally in sleep research, where we have a strong bench of researchers,” NDSU VP for Research Colleen Fitzgerald said. “Especially exciting is the furthered development of NDSU’s collaborations with Sanford Research, a valued partner on many funded projects.”

Irish and Steffen’s project will explore the relationship between sleep disturbances and binge eating behaviors while examining the bidirectional link between sleep and binge eating levels. The work will focus on identifying 24-hour patterns of sleep that may signal vulnerability to binge eating. Binge eating is defined as consuming a considerable amount of food in a discrete period accompanied by loss of control. Binge eating can cause weight gain, medical conditions such as heart disease and diabetes, problems functioning at work or social and mental health issues such as depression and anxiety. By analyzing sleep duration, variability, nap patterns, and the influence of negative affect, the study intends to pinpoint biobehavioral patterns that could improve the identification of individuals at higher risk for binge eating.

“Although research has found that poor sleep is associated with greater binge eating frequency and severity, it also seems that the relationship is quite a bit more complex,” Irish said. “My previous work has identified daytime napping as a potentially important factor in the link between sleep and binge eating, as nappers seem to engage in more severe binge eating than non-nappers.”

This new study will provide the opportunity to examine these factors better using an intensive longitudinal design. “Sleep is often easier to modify than other behaviors, such as eating behavior, so better understanding how sleep impacts binge eating can offer a new pathway to improving positive changes in eating behavior,” she added.

“With extensive expertise in how sleep and health are related, the focus of Dr. Irish’s newly funded research will address eating disorder symptomatology, an ongoing major health issue that has few proven effective treatments,” said Clayton Hilmert, Chair of the NDSU Psychology department. “Dr. Irish is taking an innovative approach by examining how sleep patterns are associated with binge eating disorder symptoms. Her approach considers how sleep during both the night and day (i.e., naps) may lead to binge eating episodes and also how binge eating episodes may impact sleep, creating a dangerous cycle of eating disorder symptoms and disrupted sleep patterns. With essential NIH funding Dr. Irish's research will help us develop better interventions for eating disorders and help us further our understanding of the role of sleep in major health issues.”

The project will involve a cohort of 230 adults with recurrent binge eating, using remote clinical screenings and a 14-day intensive assessment of sleep, affect, and eating behaviors through wrist actigraphy and ecological momentary assessment. The ultimate goal is to provide a deeper understanding of how sleep influences binge eating, contributing to improved interventions and treatment outcomes for those with eating disorders. The study could guide new, practical strategies for both momentary and traditional eating disorder treatments by focusing on modifiable targets such as sleep and affect.

Overall, the study’s goal is not to replace current binge eating treatments but rather to provide an adjunctive option to help improve outcomes for those most likely to benefit from sleep improvement. “I hope to identify better individuals for whom sleep improvement may help facilitate a reduction in binge eating,” she said. “It may not be relevant to everyone, so identifying the people for whom sleep improvement is most likely to help is an important first step in getting the right treatments to the right people.”

Irish sees the benefit of this award not only for NDSU but also for the entire state.

“The award raises the academic profile of NDSU, particularly in the study of sleep and disordered eating, which is a relatively new/small field of study,” Irish said. “The focal behaviors of my research, sleep and binge eating, are behaviors that many North Dakotans struggle with, each of which can have detrimental impacts on health and functioning. While this specific project is only one piece of the puzzle, it will contribute to advancing our ability to help people address problem behaviors that are reducing their quality of life.”

Irish’s award is NIH #1R01MH139617-01