In a study published in the journal JAMA Internal Medicine, a team from the University of Chicago and the University of Wisconsin – Madison a randomized clinical trial among 80 adults with overweight and habitual sleep of less than 6.5 hours a night.
The participants were between 21 and 40 years old and had a body mass index of 25 to 29.9, which is typically classified as overweight.
After a two – week habitual sleep period, they were randomized to either extend their sleep to 8.5 hours or continue habitual sleep.
The study authors found that those who slept longer reduced their daily energy intake by approximately 270 calories.
That would translate to roughly 26 lbs. of weight loss over three years if the effects were sustained over a long period.
Total energy expenditure did not significantly after between the two groups, resulting in a ‘negative energy balance’ with sleep extension.
The researchers measured total energy expenditure using a technique called the doubly labeled water method, which involves collecting urine samples, according to the National Center for Biotechnology Information.
‘Most other studies on this topic in labs are short – lived, for a couple of days, and food intake is measured by how much participants consume from an offered diet,’ Esra Tasali, the director of the University of Chicago Sleep Center, said in a statement. ‘In our study, er only manipulated sleep, and had the participants eat whatever they wanted, with no food logging or anything else to track their nutrition by themselves’.
The authors said their findings may have important public health implications for weight management and policy recommendations.
‘To our knowledge, this study provides the first evidence of the beneficial effects of extending sleep to a healthy duration on objectively assessed energy intake and body weight in participants who continued to live in their home environment. Modest lifestyle changes in energy intake or expenditure are increasingly promoted as viable interventions to reverse obesity’, they wrote.
Tasali explained that they ‘simply coached each individual on good sleep hygiene, and discussed their own personal sleep environments, providing tailored advice on change they could make to improve their sleep duration. Importantly, to blind participants to sleep intervention, recruitment materials did not mention sleep intervention, allowing us to capture true habitual sleep patterns at baseline’.
The doctor noted that limiting the use of electronic device before bedtime ‘appeared as a key intervention’.
According to the Centers for Disease Control and Prevention (CDC), adults ages 18 and older should get a minimum of seven hours of sleep per night.