A good night's sleep can help beat obesity, scientists have revealed, as research suggests being overtired can make you fat.
Lack of sleep has been found to create a hormone imbalance, which increases the appetite and leads to putting on weight, it is claimed.
Even partial sleep deprivation was found to be a factor in body weight regulation, with research suggesting a good night's sleep could have a significant impact in the fight against obesity.
Research found that over a third of Americans were obese and more than a quarter get less than six hours sleep a night.
Current obesity treatments were found to focus on changing lifestyles by promoting exercise and change in diet.
But changing an individual's daily routine, including sleep patterns, could be a vital step in helping to shed the pounds, it is claimed.
Sharon Nickols-Richardson, professor of nutrition at Pennsylvania State University, said: "Various investigations, although diverse, indicate an effect of partial sleep deprivation on body weight management.
"The intriguing relationship between partial sleep deprivation and excess adiposity makes partial sleep deprivation a factor of interest in body weight regulation, particularly in weight loss."
The report reviewed research papers from the past 15 years to determine the role of partial sleep deprivation on energy balance and weight regulation.
The team constructed a series of comparative tables detailing individual study populations, study designs, energy intake, energy expenditure, and measurements of the hormones ghrelin, leptin, insulin, glucose, and cortisol.
It identified a set of patterns, including reduced insulin sensitivity, increases in ghrelin, and decreases in leptin among partially sleep-deprived individuals. Changes in ghrelin and leptin influenced energy intake among the study populations.
Prof Nickols-Richardson said: "Changes in these hormones coinciding with an energy-reduced diet paired with changes in response to partial sleep deprivation may be expected to increase ghrelin and decrease leptin concentrations even further to promote hunger."
Further research was needed to determine the effects of sleep deprivation on body composition and substrate use.
The study "Partial Sleep Deprivation and Energy Balance in Adults: An Emerging Issue for Consideration by Dietetics Practitioners" was published in the Journal of the Academy of Nutrition and Dietetics Reports