Findings by Michikazu Sekine, an associate professor of public health and Sadanobu Kagamimori, a public health professor at the University of Toyama, said more children who had less than nine hours of sleep until they were 3 became obese compared to those who got over 10 hours of sleep.
Aside from sleep, the study pinpointed to lack of exercise and rich foods as contributory factors to overweight problems among Japanese.
The growing number of obese Japanese had been observed by health authorities. In the 1970s only 3 percent of the country's population were obese. The number grew to 10 percent since the 1990s.
The 10,000 participants were all born in the Toyama Prefecture and were checked every three years until they reached high school.
The Japanese finding coincides with a recent finding by the U.S. National Sleep Foundation study that poor sleep habits are closely associated with obesity, according to Dr. Joseph Ojile, head of the Clayton Sleep Institute.
Because of this finding, savants are pushing for obesity therapists to consider sleep as a major health requirement, alongside diet and exercise.
