Comparison of growth and nutritional status of Chinese and Japanese children and adolescents

Potential eating disorder exhibited with daytime functional vulnerabilities associated with sleep problems in Japanese adolescents: A cross-sectional study

OBJECTIVES

Eating disorders (ED) are serious psychiatric disorders that affect individuals, especially adolescents. It has been suggested that nonclinical ED-like characteristics are related to sleep problems. We conducted a survey of Japanese adolescents to investigate this claim.

METHOD

In this cross-sectional study, 398 adolescents aged 12-18 years responded to a self-administered questionnaire survey. We used the Eating Attitudes Test-26 (EAT-26) and the Athens Insomnia Scale (AIS) to measure potential ED and sleep problems, respectively.

RESULTS

Adolescents with potential ED had significantly higher daytime functional vulnerability potentially associated with sleep problems than those without ED. In particular, problems with a sense of well-being and physical and mental functioning during the day were significant. In contrast, no significant associations were found between potential ED and sleep initiation, awakenings during the night, early morning awakening, total sleep duration, or overall quality of sleep. Finally, nocturnal and daytime sleep scores were significantly associated with dieting, bulimia, and oral control EAT-26 subscores.

DISCUSSION

Participants with possible ED experienced problems related to well-being and mental and physical functioning, which are indicators of daytime functional vulnerability potentially associated with sleep problems. Further, adolescents with more severe ED characteristics are more likely to have a higher degree of daytime psychological vulnerability potentially attributable to sleep problems. The study suggested that professionals treating adolescent mental health issues need an approach that comprehensively integrates both sleep problems and potential ED.

Levels of Physical Fitness and Weight Status in Children and Adolescents: A Comparison between China and Japan

This study compared the physical fitness level and weight status of children and adolescents in China and Japan. Children and adolescents aged 7–18 years were recruited (China: n = 5660; Japan: n = 5660). Physical fitness was assessed using seven core items—grip strength, 30-s sit-ups, standing long jump, sit-and-reach, 20-s repeated straddling, 20-m shuttle run test, and 50-m dash. A physical fitness index (PFI) was calculated by adding all items’ Z-scores. We conducted comparisons of PFI and its distribution, each physical fitness item, and weight status for individuals from China and Japan across all ages. The PFI was lower in China than in Japan for all age groups, with an especially large difference at age 18 years for boys (a difference of 9.05) and girls (a difference of 9.10) (p < 0.001). The same result was seen for the seven items. The PFI distribution for children and adolescents was more disperse among those in Japan than among those in China. Obesity prevalence was 2.84 times higher in China than in Japan. An inverted U-shaped relationship was observed between physical fitness and nutritional status. Children and adolescents showed markedly lower physical fitness and higher obesity prevalence in China than in Japan.