Dietary and health-related characteristics of Korean adolescent night eaters

Abstract

A growing body of research indicates that delayed eating behaviours like night eating could be associated with poor diet quality, risky health behaviours and a greater risk of obesity. This study aimed to examine dietary and health-related characteristics of Korean adolescent night eaters. The present study analysed the data from one day 24-h dietary recall and a demographic survey of 1,738 Korean adolescents aged 12 to 18 years old, abstracted from the 2010-2012 Korea National Health and Nutrition Examination Survey (KNHANES). In this study, night eating was defined as consuming 25% or more out of the daily Total Energy Intake between 21:00 and 06:00, and the subjects who did this were classified as night eaters, while the rest were considered non-night eaters. Around 21% of Korean adolescents appeared to be night eaters. The results of Rao Scott Chi-square tests and t-tests indicated that adolescent night eaters showed increased breakfast skipping (p=0.001) and lower diet quality as evidenced by lower Dietary Diversity Scores (p=0.008), higher intake of energy from snacks (p<0.001) and greater proportion of energy from fat (p=0.029) when compared to non-night eaters. There were no significant differences between night eaters and non-night eaters in daily food group intake. The results from logistic regression analysis indicated that adolescents whose both parents were night eaters were 4.37 times as likely to be night eaters as those whose parents werent and male adolescents presented 1.85 times higher odds of night eating than females. Only female adolescents showed a significant relationship between night eating and BMI z-scores (β=0.28, p=0.004) in multiple linear regression analyses. According to the results of multinomial logistic regression, however, night eating did not increase the odds of being overweight or obese. Therefore, the relationship between night eating and BMI z-score was limited to female adolescents who were within healthy weight status. In summary, male adolescents as well as those whose parents were night eaters showed higher tendency to be night eaters. Also, night eating among Korean adolescents was related to delayed eating behaviours, such as breakfast skipping and lower daytime energy intake, and lower diet quality in general. These results suggest that night eating should be considered when designing nutrition education programs targeting adolescents.