By Kim Rahn
Staff Reporter
You'd better sleep for more than five hours a day if you want to get rid of those love handles.
A research team from Ajou University has found that people sleeping for less than five hours nightly are highly likely to be obese. It is the first study on the relationship between sleep and obesity among Koreans.
The study was based on health data of 8,717 adults aged between 20 and 65 in 2001 and 2005. The team divided them into five groups according to their sleeping patterns ― from less than five to over nine hours. Average nightly sleeping hours stood at 6.9.
The team categorized those whose body mass index (BMI) is over 25 as obese. The BMI is defined as an individual's bodyweight in kilograms divided by the square of his or her height in meters. Men with a waist measurement of over 90 centimeters and women with over 85 centimeters were categorized as abdominally obese.
According to the study, 36.3 percent of those sleeping less than five hours nightly were obese, and 28.8 percent of them were abdominally obese ― higher ratios than those of people sleeping less than seven hours, 30.3 percent for obesity and 21.4 percent for abdominal obesity, respectively.
The figure indicated that those in the former group have 1.25 times higher chances of becoming obese than those in the latter group, and were 1.24 times more likely to be abdominally obese, professor Kim Dae-jung of the team, said.
``Noteworthy was that the correlation between lack of sleep and obesity was more evident among those aged between 20 and 40 than older age groups. It was also more evident among men than women,'' Kim said.
He said the study shows that young people are exposed to the danger of obesity as they spend their nights working, drinking and engaged in other forms of entertainment rather than sleeping.
``The study is significant in that it showed the correlation between sleeping hours and obesity of Koreans for the first time. People are advised to have enough sleep to prevent obesity,'' Kim said.
The research was recently featured on the Web site of ``Obesity,'' a sister journal of ``Nature.''