Weight loss: study says sleeping longer could help you cut calories

Want to lower your calorie intake? Improve your sleep, and it might happen on its own, according to new research

Woman stretching and smiling in bed
(Image credit: Getty)

A study at UChicago and the University of Wisconsin–Madison looked into improving people's sleep habits, and found that more sleep had a knock-on effect on caloric intake. 

The study took the form of a four-week-long randomised clinical trial involving 80 overweight adults who typically slept less than 6.5 hours a night. After a sleep counselling session, they were able to increase their sleep duration by an average of 1.2 hours a night, bumping it up over the typical 8-hour benchmark.

With no other prescribed lifestyle changes, participants also saw their overall caloric intake decrease by an average of 270 calories per day, with lowering their intake by up to 500 calories a day. They also recorded a negative energy balance – i.e. one where caloric intake is less than calories burned. Based on those average numbers, over three years that would translate to around 12kg or 26lb of weight loss, potentially just from improving sleep hygiene. 

Previous studies have shown that sleep restriction can have knock-on effect on appetite and lead to increased food consumption, Esra Tasali, who headed up the study, told UChicago Medicine. That prompted the question if increased sleep could have the opposite effect. 

Interestingly, the research took a 'real world' approach: participants followed their normal lifestyle, with no manipulation or control of their diet or exercise regime (“This was not a weight-loss study,” said Esra). The only self-monitoring was sleep, logged using a sleep tracker

“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 told UChicago Medicine. “In our study, we only manipulated sleep, and had the participants eat whatever they wanted, with no food logging or anything else to track their nutrition by themselves.”

Another surprising takeaway was that the participants required very minor intervention to significantly improve their sleep duration. After just a single counselling session, participants increased their average sleep duration by over an hour a night. One key change, Esra noted, was to limit use of electronic devices before bedtime. For more tips, head to our article on how to sleep better at night

"If healthy sleep habits are maintained over longer duration, this would lead to clinically important weight loss over time," continues Esra. "Many people are working hard to find ways to decrease their caloric intake to lose weight – well, just by sleeping more, you may be able to reduce it substantially."

Ruth Hamilton

Ruth is a lifestyle journalist specialising in sleep and wellbeing. She has tested more mattresses than her small flat can handle and will talk at length about them to anyone who shows even a passing interest, and has had to implement a one-in-one-out pillow policy for fear of getting smothered in the night. As well as following all the industry trends and advancements in the mattress and bedding world, she regularly speaks to certified experts to delve into the science behind a great night's sleep, and offer you advice to help you get there. She's currently Sleep Editor on Tom's Guide and TechRadar, and prior to that ran the Outdoors and Wellness channels on T3 (now covered by Matt Kollat and Beth Girdler-Maslen respectively).