Relationships among Sleep Time, Physical Activity Time, Screen Time, and Nutrition Literacy of Adolescents: A Cross-Sectional Study in Chongqing, China.

Background: Unhealthy lifestyles among adolescents are reaching alarming levels and have become a major public health problem. This study aimed to assess the relationship between sleep time, physical activity (PA) time, screen time (ST), and nutritional literacy (NL). Methods: This cross-sectional online study involving adolescents aged 10-18 years was conducted in September 2020 in 239 schools in Chongqing, China. NL was measured using the "Nutrition Literacy Scale for middle school students in Chongqing (CM-NLS)". According to the recommended by the Chinese dietary guidelines (2022), we divided the sleep time of junior high school students into <9 h and ≥9 h, high school students into <8 h and ≥8 h, divided the workdays into weekend PA time < 1 h and ≥1 h, and divided the workdays into weekend ST < 2 h and ≥2 h. The multinomial logistic regression model was used to examine the association. Results: A total of 18,660 adolescents (50.2% males) were included. The proportion of participants that were junior high school students and attended boarding schools was 57.2% and 65.3%, respectively. Compared with senior high school students, junior high school students had a higher level of NL. Whether on workdays or weekends, participants with sleep time ≥ 8/9 h, PA time ≥ 1 h, and ST < 2 h per day had higher levels of NL. On weekdays, participants who met the sleep time ≥ 8 h/9 h (OR = 1.48, 95% CI: 1.36, 1.62) and PA time ≥ 1 h (OR = 1.69, 95% CI: 1.59, 1.81) had higher reporting of NL levels. Conclusions: Sleep time, PA time, and ST were positively correlated with NL among adolescents, especially junior high school students.

Understanding and Use of Nutrition Labels of Prepackaged Food by University Students: A Cross-Sectional Study in Chongqing, China.

OBJECT: The correct use of nutrition labels for prepackaged food helps university students develop healthy eating habits and prevent the occurrence of chronic non-communicable diseases. This study evaluates the understanding and use of nutrition labels of prepackaged food by university students in four different fields of study in Chongqing, China. METHODS: This cross-sectional study used an online survey platform conducted in July 2022 in colleges and universities in Chongqing, China. The convenience sampling method was used to select students in four different fields of study, including medicine, humanities, science and technology, and arts and sports. Ten questions were used to assess participants' understanding of nutrition labels. A score of six or above (60%) indicates that the respondent has a basic understanding of the nutritional labels of prepackaged food. Descriptive statistics and generalized linear models (GLMs) were used to assess participants' understanding and use of nutrition labels for prepackaged foods and their influencing factors. RESULTS: A total of 1262 valid questionnaires was collected. The average age of the participants was 21.8 years (SD: 2.43), 50.1% were male, 80.8% were ethnic Han, and 50.9% were from rural areas. Only 21.3% of the university students in Chongqing had a good understanding of the nutrition labels of prepackaged food, where medical students were the highest (39.9%) and science and engineering students were the lowest (15.6%). Gender, ethnicity, grade, major, and whether received courses related to nutrition were influential factors in the understanding and use of nutrition labels of prepackaged food. Medical students also had more positive attitudes toward nutritional labels of prepackaged food. CONCLUSIONS: Understanding and use of nutrition labels for prepackaged food by university students in Chongqing are unsatisfactory. Student's major was a significant influencing factor in nutrition label comprehension, with medical students having the greatest understanding. Based on these results, we suggest that nutrition and health courses should be popularized among non-medical students to narrow the differences between different fields of study. For university students in all fields of study, education and publicity of nutrition labels of prepackaged food are needed, not only in the classroom but also in daily life.