Thanks to grants from the American Diabetes Association (ADA) and National Institutes of Health (NIH), Chantelle Hart, an associate professor of social and behavioral sciences in the College of Public Health and research scientist at the Center for Obesity Research and Education (CORE), is exploring how children’s sleep patterns affect weight regulation and the risk of developing Type 2 diabetes.
Her studies represent a shift in direction from previous work in this area. Most research examining the effect of children’s sleep on obesity and diabetes risk has been observational and focused on how much they sleep. Hart’s current work, however, uses randomized controlled study designs to focus on the importance of enhancing both sleep duration and consistency of sleep patterns on glucose regulation as well as how enhancing sleep affects weight regulation when combined with improving targeted eating and activity behaviors.
“Previously, we enhanced the number of hours children slept and stabilized the timing, and observed improvements in eating and activity behaviors in a short period of time,” said Hart. “But, we cannot untangle which drove the observed changes in obesity-related risk factors.”
Hart’s ADA study, funded by a $600,000 grant, will enroll African-American children with overweight and obesity, a group at increased risk for developing Type 2 diabetes. All children will be asked to sleep as they normally do for a week. Then, each child follows a randomly chosen schedule for four weeks.
One group will stabilize their sleep patterns, meaning they’ll go to sleep and wake up at the same times each day, and increase their sleep duration by 90 minutes each night. Another will stabilize sleep and increase it by 45 minutes each night. A third only stabilizes their sleep pattern and the fourth continues with their normal sleep habits.
“Hopefully we’ll have a signal of which approach may be helpful for decreasing diabetes risk in children,” said Hart.
The NIH study, funded by a five-year, $3.78 million grant, assesses the relative efficacy of two approaches to weight regulation in school-aged children. While both studies examine the effect of sleep on diabetes risk, this study focuses more on the role sleep plays in weight regulation.
“There are potentially many ways sleep can affect obesity risk,” Hart explained. “In this study, we will be able to compare how improving children’s sleep alone, compared to improving sleep along with targeted eating and activity behaviors, affects weight regulation over 12 months.”
African-American children eight to eleven years old will be randomly assigned to one of two groups. Hart will ask children in the first group to increase the amount they sleep each night by approximately one hour. Children in a second group will be asked to increase their sleep and improve targeted eating and activity behaviors such as watching less television, drinking fewer sugar-sweetened beverages, and increasing physical activity.
“We’re trying to determine if sleep is an important, novel strategy for weight regulation,” Hart explained. “We have some promising evidence from preliminary studies, and this new study will help determine if sleep, in and of itself or when combined with other effective strategies, is important.”