Sleep and Obesity
Insufficient sleep is a potential risk factor for obesity along with the two most commonly identified risk factors: lack of exercise and overeating. During sleep, our bodies secrete hormones that help to control appetite, energy metabolism, and glucose processing. Poor sleep leads to an increase in the production of cortisol and increase in the secretion of insulin following a meal. Insulin regulates glucose processing and promotes fat storage, therefore higher levels of insulin are associated with weight gain and are a risk factor for diabetes. Insufficient sleep is also associated with lower levels of leptin, a hormone that produces satiety, as well as higher levels of ghrelin, a biochemical that stimulates appetite. As a result, poor sleep may result in food cravings even after we have taken in adequate number of calories. We may also be more likely to eat foods such as sweets that satisfy the craving for a quick energy boost. Furthermore, insufficient sleep may leave us too tired to burn off these extra calories with exercise.