BEIJING, Sept 7 —New research has found that Chinese children who go to bed later and sleep less are more likely to be overweight, adding to the body of evidence that suggests a shorter sleep duration is linked to a higher risk of obesity in children.
Carried out by the University of Birmingham, UK, along with researchers from Sun Yat-Sen University and Guangzhou Centre for Disease Control and Prevention, the teams looked at the sleeping habits of 2,795 children aged 9 to 12 from the city of Guangzhou, in southern China.
The team used questionnaires to gather information on children’s sleep duration on typical weekdays and weekends and their sleep quality, and also took measurements and calculations of the children’s weight, height, and waist circumference, Body Mass Index and percentage body fat.
In line with previous studies, the results showed that children sleeping longer had lower Body Mass Index (BMI) scores than those who slept less, with the team finding that for every hour later a child goes to bed, their BMI score also increases by a small amount.
Although a small increase may seem insignificant, there is evidence that even a small change in BMI score is clinically important and could lead to significant health changes.
The results also suggested that going to bed later may still increase the risk of obesity even if children are getting ‘enough’ sleep over the course of the night.
Professor Peymané Adab also added that other behaviors which can contribute to obesity—such as watching TV and snacking—were also more common in the later evening.
The research found that Chinese children slept less than their American and European counterparts and had a later bedtime, possibly due to the focus on studying and high academic achievement in China.
“The prevalence of obesity in China is alarming as the country undergoes rapid economic transition, leading to changes to traditional diet, increased sedentary lifestyles and reduced physical activity,” commented co-author Professor Yajun Chen.
“There are complex factors contributing to childhood obesity including biological and lifestyle factors, but increasing observational research reports that shorter sleep duration may be an additional risk factor associated with higher body mass index (BMI) among children.”
Despite the increasing evidence that a sufficient amount of high-quality sleep is important for overall health, sleep duration is decreasing among both children and adolescents in countries around the world.
The results can be found published online in the Journal of Epidemiology. — AFP-Relaxnews
