People who consistently overeat during nighttime hours, in conjunction with agitated moods and disrupted sleep patterns, may have more than a bad routine – they have a clinical disorder called night eating syndrome. The syndrome is both a sleep and eating disorder and may affect up to 10 million people, including those who are at normal body weights. Night eating syndrome is characterized by “morning anorexia,” in which the person doesn’t eat during morning hours and continues to take in a reduced level of calories during the day. As evening approaches, the person’s mood usually becomes more negative along with feelings of depression. During the evening, the patient overeats, consuming high-calorie foods several times a night. A night eater can typically consume more than half of their entire calories for the day during the evening hours. The anxious feelings and depressed state continue through the night, along with the eating episodes. In addition to excess calories consumed, sleep patterns are highly disturbed. The disorder is different than other eating disorders, such as bulimia, because the night eater consumes several small meals or snacks over a period of hours instead of one larger food binge episode. During the eating episodes, the person usually experiences anxious feelings or tension; in the morning, there are feelings of shame. Albert Stunkard, M.D. and faculty of the University of Pennsylvania Weight and Eating Disorders Program, says people with night eating syndrome are affected by hormone imbalances and changing hormone levels, and the problem is much more than just a coping behavior. He suggests those with night eating syndrome tend to medicate themselves with food during the night, especially since foods high in carbohydrates can bring on higher levels of serotonin – a hormone linked to sleep. Researchers at the University Hospital in Tromso, Norway, studied biological processes during 24-hour intervals to explore levels of cortisol, plasma melatonin and leptin. These are the hormones connected to appetite and sleeping, and are typically found to be under-produced in patients who suffer from night eating syndrome.For non-night eaters, increasing levels of melatonin usually signals the onset of sleep. At the same time, leptin increases during the evening, a hormone that turns off the hunger signals. However, night eaters show lower than normal levels of melatonin, leptin levels that do not rise during the evening and higher than normal levels of cortisol throughout the entire day, the hormone produced by stress. Night eating syndrome is recognized by the International Classification of Sleep Disorders and often occurs along with mood disorders or depression. Further research is called for to explore this complex condition that is simultaneously a sleep disorder and an eating disorder.
Recommended Reading: Night Eating Syndrome on Eating Disorder Treatment