The Sleep-Weight Connection
But, surprisingly, the same study found that overweight people who had difficulty sleeping were extra-active in the daytime.
Scientists believe poor sleep and stress may result in a lack of organization, leading to more last-minute "rushing about" to get things done. This in turn could contribute to stress-eating.
Researchers in the U.S. analyzed the sleep activity and energy expenditure of 14 volunteer nurses at the Walter Reed Army Medical Centre in Washington DC.
Each participant wore an arm band that measured movement, temperature, body position and other indicators of activity and rest.
Those identified as "short sleepers" had an average body mass index (BMI) of 28.3 compared with 24.5 for "long sleepers".
BMI is a widely used measurement that links weight and height. People with a BMI of 30 or above are said to be clinically obese. "Normal" is defined as 18.5 to 24.9, and "overweight" 25 to 29.9.
The study found that short sleepers were, on average, verging on obese while long sleepers were at the upper end of the normal range.
Short sleepers tended to have greater difficulty getting to sleep and staying asleep.