As you get older, you start to realise more and more how important sleep is to your wellbeing. However, what you might not realise is that lack of sleep not only affects your mental health and energy levels, it also causes you to gain weight. This is according to a new study, published this week in the journal Nature Communications, which found that the less sleep you get, the more you crave calorie-packed foods.
For the research, investigators at the University of California, Berkeley, scanned the brains of 23 healthy young adults. Using a functional magnetic resonance imaging (fMRI) machine, which allows scientists to see your mind working in real time, the researchers looked at scans of the brains after a good night’s sleep, and at scans after a restless night. While scanning the participants’ brains, the researchers showed them images of healthy and unhealthy food.
When you don’t have enough quality sleep, this affects the frontal lobe in your brain, the researchers found. The results of the study revealed that the frontal lobe, which is responsible for complex decision-making, was impaired when the participant’s hadn’t had enough sleep. Moreover, scans of deeper activity in the brain showed that the test subjects wanted greater rewards. Within the context of the study, this meant that the subjects selected “rewards” such as high-calorie junk foods like pizza and doughnuts more often than healthy foods such as fruits and vegetables.
Senior author Matthew P. Walker, a UC Berkeley assistant professor in psychology, commented in a press release, ‘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. This combination of altered brain activity and decision-making may help explain why people who sleep less also tend to be overweight or obese.’ He added that as getting adequate sleep makes eating healthier that much easier, it can play an important role if you’re looking to improve your wellness, or to shed a few pounds. It is recommended that you get seven to nine hours of good quality sleep every night.