The Education Ministry said Tuesday almost half of all high school students slept for six or less hours a day, illustrating the academic pressure placed on Korean students.

According to the ministry, 44.5 percent of students in high school got no more than six hours of daily sleep in 2013. The rate was significantly higher than the proportion of students in middle and elementary schools, which were 10.6 percent and 3.8 percent each.

It is commonly recommended that teenagers get at least seven to eight hours of sleep every day.

Guidelines by the U.S. National Health Institute puts the ideal amount of sleep for teenagers at nine to 10 hours a day. A research team from Brigham Young University recommended seven hours a day in a paper published in the Eastern Economic Journal.

Although the ministry data did not specify the reason for the lack of sleep, the latest survey by the National Youth Policy Institute showed that more than half of high school students blamed schoolwork for lack of sleep.

According to the survey, the average amount of sleep that high school students got dropped from six hours and 30 minutes in 2009 to five hours and 27 minutes in 2013.

The ministry data also showed that the percentage of students who were obese increased from 14.7 percent in 2012 to 15.3 percent last year. The obesity rate increased as students got older, with 17 percent of high school students being obese.

The data implied that students’ eating habits could be deteriorating. The percentage of students eating fast food at least once a week increased in all age groups compared to last year, and the figure was highest among high school students with 71.1 percent.

On the contrary, only 24.3 percent of high school students ate vegetables every day, lower than that of middle school (27.1 percent) and elementary school students (31.1 percent).

The ministry vowed to make concerted efforts with families, schools and local communities to help students maintain their health.

By Yoon Min-sik (minsikyoon@heraldcorp.com)