Grant: Operating Grant

The current obesity "epidemic" in the developed world is a major health concern; over half of adult Canadians are now classified as overweight or clinically obese. A particularly worrisome trend is the increased prevalence of obesity in young people. Although the reason(s) for increasing obesity rates remain unclear, one important factor is the role that stress plays in overeating and weight gain. Stress changes the way we eat resulting in a shift in food choices away from healthy foods to more fatty, energy dense foods (comfort foods). Youth are particularly vulnerable to the effects of stress making this an ideal time window to examine the relationship between stress and eating. We recently showed that adolescent rats exposed to stress displayed increased anxiety later in life. Interestingly, these effects were reduced or absent if rats were allowed to eat comfort food during and after the stress exposure. Although this suggests that eating comfort food is beneficial, this high fat/carbohydrate diet, combined with stress also resulted in signs of metabolic syndrome and obesity. The current proposal aims to explore the potential chemical processes that are altered in the brain (during adolescence) that might contribute to the increased comfort food consumption, and how these comfort foods may reduce signs of stress. In particular, the experiments will focus on the role that a chemical messenger (bombesin-like peptides) plays in this process. Bombesin-like peptides, which are located in feeding and reward centers of the brain, are released when comfort foods are eaten and also during stress and therefore might be important in the proces(es) by which comfort foods reduce levels of stress. It is hoped that these studies will help us understand why we might choose to eat comfort food during times of stress and how it makes us feel better. Ultimately this research may point to new interventions for the prevention and treatment of obesity.