A new study has indicated that those who sleep for longer are more likely to be slim than shorter sleepers. Monitoring the weight of a group of nurses from the U.S, the team from the Walter Reed Army Medical Centre in Washington discovered that shorter sleepers had an average BMI of 28.3, 3.8 points higher than the average BMI of longer sleepers.
Previous studies in the U.S had suggested that people sleeping less that 7 to 9 hours a night were up to 75% more likely to be overweight. It is believed the link between sleep and excessive weight is caused by the release of hormones that affect hunger and a person’s rate of metabolism.
Dr Eliasson, who led the study, believes that not only may too little sleep be affecting hormone levels but also thinks that stress may be affecting time spent asleep, the quality of sleep and different modes of behaviour. He explained that if stress was affecting sleep, then it might combine with someone feeling less rested and cause them to be less organised than someone at a normal weight. They therefore might be taking more steps and trips in order to accomplish the same tasks as someone at a normal weight. Overweight people do tend to take more steps and be more active than those without weight problems, walking 14,000 steps a day compared to 11,300. All these different factors could also combine to push someone towards other behaviours, like stress eating that would damage their health.
Dr Eliasson now hopes that time can now be spent on discovering more about what was driving the difference in weight between the two groups. They are eager to start a study which would allow for the variety of known influences on weight gain and are planning on doing further research into the role stress plays on sleep and metabolism.