How sleep deprivation is linked to weight gain in kids

She is troubled by the alarming numbers of overweight and obese children in Canada.

“Obesity is a significant risk factor for several chronic illnesses, and it contributes to the economic burden of society,” says Jarrin, a graduate of Concordia’s Department of Psychology. “Many obese children will grow up to become obese adults who will be plagued with lifelong health conditions. This is a societal concern.”

Jarrin dedicated her Concordia research to better understanding the causes of childhood obesity. During her graduate work she found that sleep, or lack thereof, is a major contributing factor in weight status among children.

Short sleep = Heavier weight

“Short sleep duration has been consistently associated with heavier weight, even among children,” she says. “Until now, we didn’t really know how this happens. Both my master’s and doctoral work at Concordia examined how the body responds to shorter sleep and how these physical changes may lead to heavier weight and larger waists.”

Jarrin, with the support of her supervisor Jennifer McGrath, an associate professor in Concordia’s Department of Psychology and director of its Pediatric Public Health Psychology Lab, looked at heart rate variability (HRV) as a measure of autonomic balance and as a stress-response indicator. Autonomic balance indicates if the body’s fight-orflight system is properly reacting and functioning well in response to daily activities.

“We hypothesized that chronic lack of sleep leads to an imbalance of the body’s autonomic system, as well as hormone dysregulation. Autonomic imbalance and altered hormone secretion, in turn, leads to increased appetite, especially for salty and fatty foods,” she says.

Jarrin’s findings showed that heart rate variability was, indeed, a plausible link between poor sleep and obesity among children and adolescents. “Our study is the first to show that autonomic imbalance, as measured by HRV, partly explains how inadequate sleep could lead to obesity. This work emphasizes the importance of good sleep routines during childhood and adolescence,” says Jarrin.

Improved sleep = Improved weight?

Jarrin suggests that the association between lack of sleep and weight status might be reversible. “I believe that better sleep, combined with other healthy lifestyle behaviours, can lead to improved autonomic regulation and reduced risk for obesity,” she says.

What does this mean for parents? They need to establish consistent routines and good sleep patterns for their children.

“Want a healthy child? Start with sleep,” says Jarrin. “Children should sleep between eight and 10 hours each night and adolescents should get between eight and nine hours. And it is not just about the amount of time spent sleeping — a steady routine is especially important. Youth should get to bed early rather than late, with regular bedtimes and wake times, even on weekends. Bedrooms that promote sleeping are cool, quiet spaces without televisions or electronic gadgets such as phones or tablets.”

Support at Concordia

Jarrin credits Concordia’s supportive environment and McGrath’s lab in helping her successfully complete her graduate studies. “This was the first sleep study completed in the Department of Psychology and I was fortunate to be part of such a collaborative team. I am very passionate about this work and my enthusiasm was encouraged.”

Her passion was well rewarded, as Jarrin was the recipient of several grants and bursaries including an entrance scholarship from Concordia, the Frederick Lowy Scholars Fellowship and the J.P. Zweig Graduate Scholarship. She also obtained a fellowship from the Social Sciences and Humanities Research Council of Canada and received a Canadian Psychological Association Certificate of Excellence Award for best PhD thesis as well as the Society of Behavioral Sleep Medicine’s Student Dissertation Award.

Since graduating, Jarrin has received accolades for her accomplishments, including the Young Investigator Award from the American Academy of Sleep Medicine and the “Rising Star” Award from the American Psychosomatic Society.