A good night's sleep is not only important for a healthy, functioning brain and body, but for maintaining a healthy weight as well, the Daily Mail reports, as a new study from California reveals that sleep deprivation can make you crave junk food.
Researchers from the University of California, Berkeley used functional magnetic resonance imaging (fMRI) to scan the brains of 23 healthy young adults, first scanning them after a normal night's sleep and then after a sleepless night. The brain's frontal lobe, which controls complex decision-making, was found impaired after a night of insomnia, but increased activity in reward centers of the brain were discovered as well.
"What we have discovered is that high-level brain regions required for complex judgments and decisions become blunted by a lack of sleep, while more primal brain structures that control motivation and desire are amplified," Professor Matthew Walker, a UC Berkeley professor of psychology and neuroscience, told the Daily Mail. "High calorie foods also became significantly more desirable when participants were sleep-deprived. This combination of altered brain activity and decision making may help explain why people who sleep less also tend to be overweight or obese."
The researchers measured the brain activity of participants as they viewed a series of 80 different foods, ranging from low to high-calorie options like strawberries, apples and carrots to burgers, pizza and doughnuts, and rated their desire for each item. After the MRI scan, they were given whatever food they craved as incentive.
Previous studies on sleep and eating habits has found that our bodies crave more salt and sugar when we're overtired, though the latest study sheds "light on how the brain becomes impaired by sleep deprivation, leading to the selection of more unhealthy foods and, ultimately, higher rates of obesity," according to Stephanie Greer, a doctoral student in Walker's Sleep and Neuroimaging Laboratory.
However, the results also show a positive link between healthy sleep and healthy eating. "Getting enough sleep is one factor that can help promote weight control by priming the brain mechanisms governing appropriate food choices," Walker said.
