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Page 22 | Abby's Magazine - www.AbbysMag.com Losing sleep tends to make people eat more and gain weight, and now a new study suggests that one reason may be the impact that sleep depriva on has on the brain. The research showed that depriving people of sleep for one night created pronounced changes in the way their brains responded to high-calorie junk foods. On days when the subjects had not had proper sleep, fa ening foods like potato chips and sweets s mulated stronger responses in a part of the brain that helps govern the mo va on to eat. But at the same me, the subjects experienced a sharp reduc on in ac vity in the frontal cortex, a higher-level part of the brain where consequences are weighed and ra onal decisions are made. The findings suggested that one unfortunate result of sleep loss is this "double hit" in brain ac vity, said Ma hew P. Walker, an author of the study and a professor of psychology and neuroscience at the University of California, Berkeley. A sleepy brain appears to not only respond more strongly to junk food, but also has less ability to rein that impulse in. Some experts have theorized that in a sleep- deprived state, people eat more food simply to make up for all the calories they expend as they burn the midnight oil. But the new study showed that the changes in brain ac vity were evident even when the subjects were fed extra food and not experiencing any increased sensa ons in hunger. "Their hunger was no different when they were sleep deprived and when they had a normal night of sleep," Dr. Walker said. "That's important because it suggests that the changes we're seeing are caused by sleep depriva on itself, rather than simply being perhaps more metabolically impaired when you're sleep deprived." The rela onship between sleep loss and weight gain is a strong one, borne out in a variety of studies over the years. Large popula on studies show that both adults and children are more likely to be overweight and obese the less they sleep at night. In smaller, controlled studies, scien sts find that when people are allowed to sleep eight hours one night and then half that amount on another, they end up ea ng more on the days when they've had less sleep. One pivotal study at the University of Colorado in March showed that losing just a few hours of sleep a few nights in a row caused people to pack on an average of about two pounds. Other studies have found that the underlying effects of sleep depriva on on the body can in many ways be pronounced. The stress hormone cor sol climbs and markers of inflamma on rise. Hormones that s mulate appe te increase, while hormones that blunt it drop. People become less sensi ve to insulin, raising their risk of Type 2 diabetes. But un l now, few if any studies have looked at precisely what goes on in the brain when people are starved of sleep and then faced with food decisions. In the new study, which was published in the journal Nature Communica ons, Dr. Walker and his colleagues recruited 23 healthy men and women and assigned them to two different regimes, each separated by about a week. On one occasion, the subjects came into the lab and got a normal night of rest – roughly eight hours – before waking up to a small breakfast of toast and strawberry jam. The subjects then looked at 80 pictures of a variety of foods and were asked to rate how strongly they wanted them while an imaging machine measured brain ac vity. The subjects were told that a er looking through the pictures, they would receive one of the foods that they rated the highest. On another occasion, the subjects followed the same rou ne, but this me, instead of sleeping, they stayed awake through the night. They were also given snacks – like apples and peanut bu er crackers – to offset any extra calories that they burned while staying awake. The research showed that when the subjects were bleary-eyed and sleep- How SLEEP LOSS Adds To WEIGHT GAIN By Anahad O'Connor