Grant: CIHR New Investigator

One in four Canadian children is overweight or obese. Over the past 25 years, the level of overweight and obesity has doubled. This is worrying because it has long term health consequences. Childhood obesity increases risk for many diseases such as high blood pressure, heart disease, and diabetes. While obesity levels have been rising, the amount of time children spend sleeping has been decreasing. Recently, researchers found that children who sleep less have a larger body size. Even small decreases in children's sleeping time are related to greater body size. It is not clear why sleep and obesity are linked. Researchers have started to look at many factors that may explain the link between sleep and obesity. Some factors include hormones dealing with appetite, stress, breathing problems during sleep, eating habits, and changes in metabolism and sensitivity to insulin. Most researchers look at these factors singularly. Also, most studies use only self (or parent) reports of sleep times. This may not be the best way of capturing what happens during sleep. The goal of the current project is to consider three pathways that may link sleep to obesity at the same time to see how they are related. These three pathways include activation of the body's stress system, changing hormones associated with appetite, or altering how the body metabolizes glucose. Sleep will also be measured objectively using a device to measure brain activity when children sleep at home. The project will result in new information about why sleep may be linked to obesity. This information might then be able to help prevent and treat obesity.