Heavy Studies Turning Korean Children into Night Owls

Korean children are becoming more and more nocturnal. A team of researchers at Yeungnam University Medical Center led by psychiatry professor Seo Wan-seok surveyed the sleeping habits of 3,506 children between 7 and 12 years old living in Daegu, and compared the results with those of children in five other countries.

The Korean children had the shortest sleeping hours, at eight hours and 40 minutes on average. Swiss children averaged nine hours and 58 minutes of sleep, and American children (7 to 10 years old) nine hours and 28 minutes. First graders in Korea usually went to bed at 10:09 p.m., second graders at 10:19 p.m., and third graders at 10:23 p.m. The bedtime hours progressed by age, with sixth graders sleeping at 10:59 p.m.

Tutoring and after-school private lessons are the main reasons behind this "nocturnalization" of Korean children. "Children are spending an average of two hours and six minutes a day in crammers," Seo said. "The more time they spend in such institutes, the less amount of sleep they get." Changing patterns of family life, including the shift to double-income households, is also contributing to the phenomenon.

Recent studies have also blamed the lack of sleep on children's physical environment. Excessively bright lighting, and "light pollution" from computers and TVs can make sleeping more difficult. Han Jin-kyu, a sleep specialist and director of the Seoul Sleep Center, said, "In advanced countries, there are efforts to help people sleep better by using indirect lighting or yellowish light bulbs. But in Korea people use energy-efficient but very bright lights which interfere with children going to sleep."

Some statistics also support arguments that children who live in high-rise apartment buildings are going to bed later than those in low-rise houses. In Seo's paper, children in Hong Kong and Korea, countries with numerous high-rise apartment buildings, got the least amount of sleep.