Background: Depression in children and adolescents is a rising concern in China. Dietary behavior is a critical determinant of mental health. Meal timing, or the schedule of meal consumption, has been related to several metabolic disorders. However, the effect of meal timing on mental health is scarce, particularly in children and adolescents who are in a critical period of physical and psychological development. Objective: This research examined the relationship between meal timing and depression in children and adolescents in China. Methods: Children and adolescents from grades 1 to 9 were recruited from 16 districts in Shanghai, China, from January 3 to January 21, 2020. Ten schools attended the study. A survey was distributed to the students and their parents to collect demographic and health-related information. Depression was measured by the Children’s Depression Inventory-Short Form. Breakfast consumption was analyzed as a binary outcome. Participants were defined as breakfast consumers if they never skipped breakfast during the week. They were otherwise defined as breakfast skippers if they skipped breakfast at least once per week. A similar categorization was applied to analyze food intake proximal to bed. Daily eating windows were calculated using the last food intake time frame—the first food intake time frame. Participants were classified into eating window groups of less than 10 hours, 10-12 hours, and more than 12 hours. A logistic regression model was used to compute the odds ratio (OR) and 95% CI. Results: A total of 6874 participants were included in the analysis. Participants who skipped breakfast were associated with a 2.70 times higher occurrence of depression (OR 2.70, 95% CI 2.24‐3.26; P<.001). The prevalence of depression was 1.28 times higher in participants who ate before bed than in those who never ate before bed (OR 1.28, 95% CI 1.08‐1.50; P<.001). The occurrence of depression was 1.37 times higher if the eating time window was shorter than 10 hours (OR 1.37, 95% CI 1.08‐1.73; P=.009) and 1.23 times higher if the eating time window was longer than 12 hours (OR 1.23, 95% CI 1.01‐1.50; P=.004). The lowest occurrence of depression was observed at 11.5 hours. Subgroup analysis showed that such relationships remained significant in adolescents aged 10 years or older. In children, only skipping breakfast was associated with a higher odds of depression (OR 2.77, 95% CI 1.94‐3.96; P<.001). Conclusions: Breakfast skipping and eating before bed significantly increase the occurrence of depression. The optimal daily eating window to lower the occurrence of depression is 11.5 hours in children and adolescents. Daily eating windows longer than 12 hours or shorter than 10 hours are associated with an elevated occurrence of depression. Current findings advocate evidence-based dietary strategies to prevent and treat depression in children and adolescents.

(1) Background: Sedentary behavior is increasing in all age groups and is one of the most common lifestyles that is a risk factor for overweight and obesity; however, few studies have evaluated the impact of leisure-time sedentary behavior on overweight and obesity. This study aims to examine the distribution characteristics of different leisure-time sedentary behaviors and their effects on excessive weight in different age groups in the Chinese population to provide evidence for the development of behavioral interventions. (2) Methods: This study utilizes data from the 2004 to 2011 China Health and Nutrition Survey (CHNS). Participants ranged in age from 6 to 18 years or older and were from China. Weight and height were measured in the physical examination, and the sedentary behavior times during leisure periods were collected by using a questionnaire. Logistic regression models were performed for association analyses. (3) Results: A total of 36,169 participants were included in this study. The impact of screen-based sedentary leisure time on excessive weight is greater in middle-aged and older adults. For middle-aged adults, sedentary time periods spent on the Internet or video games were found to be significantly and positively associated with excessive weight (OR, 1.122, 95% CI, 1.005–1.253). In addition, for older adults, sedentary time periods spent watching television or videos were found to be significantly and positively associated with excessive weight (OR, 1.065, 95% CI, 1.035–1.095). (4) Conclusions: This study helps grasp the target population and provide evidence for the development of behavioral intervention guidelines.

Background: This study aimed to investigate the changes in distinct types of screen time and explore their longitudinal association with children and adolescents’ weight status. Methods: A two-wave longitudinal study was conducted among 2228 children and adolescents (6–19 years) in Shanghai, China, before and during the pandemic. Recreational screen time (watching TV/videos, online gaming, using social media, and browsing webpages), educational screen time (online homework and online class), and BMI were measured using a self-reported questionnaire. Mixed-effects models were constructed to assess the associations between screen time and weight status. Results: The prevalence of overweight and obesity was 20.5% and 10.2% at baseline, respectively. Both recreational and educational screen time increased significantly over two months. While recreational screen time was found to be a risk factor for obesity, it was not the case for educational screen use. Specifically, adolescents who spent more time watching TV/videos had a higher obesity risk (OR = 1.576). No significant associations were found in children. Conclusions: Overweight and obesity were prevalent among children and adolescents in China. Reducing screen-based activities is a promising strategy to prevent unhealthy weight gain in Chinese children and adolescents, while it is necessary to consider the content and distinguish between educational and recreational screen use.