Leisure-time and study-time Internet use and dietary risk factors in Korean adolescents

The effect of Internet use on adolescent nutritional outcomes: evidence from China

BACKGROUND

The increasing prevalence of adolescent overweight and obesity poses significant public health challenges, particularly in China. With the rapid adoption of the Internet, adolescents' lifestyles, including dietary habits and physical activity levels, have undergone substantial changes. However, the causal relationship between Internet use and adolescent nutritional outcomes, especially in transitional economies, remains underexplored.

METHODS

This study employs longitudinal data from the China Health and Nutrition Survey (CHNS) and China Family Panel Studies (CFPS) to investigate the impact of Internet use on adolescents' BMI-for-age z-scores and overweight status. An endogenous switching regression (ESR) model addresses potential self-selection bias. Heterogeneity analyses examine urban-rural and gender differences, while mechanism analyses identify dietary pathways influencing outcomes.

RESULTS

Internet use increases BMI-for-age z-scores and the likelihood of being overweight among adolescents, with more intensive Internet use further amplifying these effects. These effects hold across urban and rural areas as well as for both boys and girls, though the magnitude may vary. Mechanism analyses suggest that Internet use enhances protein intake while also leading to higher consumption of fast food and soft drinks.

CONCLUSION

Internet use increases BMI-for-age z-scores and overweight risks among adolescents, reinforcing the need for targeted interventions to mitigate its negative health impacts. Policies promoting healthier online behaviors and better access to nutritional education are essential to ensuring that adolescents develop healthy lifestyle habits in the digital age. Addressing these challenges can help policymakers develop equitable health strategies for adolescents in transitional economies.

Bytes and bites: social media use and dietary behaviours among adolescents across 41 countries

BACKGROUND

To examine the associations of problematic and excessive social media use (SMU) with dietary behaviours of adolescents.

METHODS

We analysed the 2017/2018 Health Behaviour in School-aged Children survey data, involving 222,865 adolescents (51.8% girls) from 41 countries. A dietary intake score was derived using consumption of fruits, vegetables, sweets, and sugary soft-drinks. Breakfast intake was categorised as daily or non-daily. Excessive SMU assessed how often respondents had online contact through social media, and problematic SMU was assessed through symptoms of addiction.

RESULTS

Regression analyses showed that adolescents reporting problematic SMU had 54% lower odds in boys (OR 0.46; 95% CI 0.42-0.51) and 64% lower odds in girls (OR 0.36; 0.33-0.40) of reporting good dietary intake compared with poor intake. Excessive SMU was also associated with lower odds of reporting good dietary intake. Problematic SMU associated inversely with daily fruit and vegetable intake, while excessive SMU was positively associated with daily fruit and vegetable intake across sex. Both types of SMU were linked to increased intake of sweets and sugary drinks and decreased breakfast consumption.

CONCLUSIONS

Problematic SMU was associated with poor dietary habits, while excessive SMU showed mixed findings. Prospective research is warranted to understand the causal mechanisms.

IMPACT

Problematic and excessive social media use (SMU) was associated with poor dietary habits with problematic SMU being more detrimental than excessive SMU. This research contributes to the literature by demonstrating that problematic and excessive SMU correlate differently with adolescent dietary habits, highlighting the need for targeted approaches to promote healthier eating. Adolescents should be encouraged to use social media responsibly, while social media companies should promote local fresh food options to enhance healthy dietary habits.

The relationship between youth's exposure to unhealthy digital food marketing and their dietary intake in Canada

There is limited evidence on how exposure to digital marketing of unhealthy foods affects youth's dietary behaviours. This study therefore aimed to examine the association between youth's self-reported digital food marketing exposure and dietary intakes, and explore predictors of frequent unhealthy food consumption. A survey was conducted among 1075 youth in Canada (aged 10-17 years) in April 2023. Proportional odds models examined associations between frequency of exposure to digital marketing of unhealthy foods and frequency of consumption of those foods, adjusted for sociodemographic characteristics and digital device usage. Compared with participants reporting no exposure to digital fast-food marketing in the past week, those exposed ≥4 times per week were more likely to consume fast food more frequently. Youth exposed to digital marketing of sugary drinks and salty/savoury snacks ≥1 time(s) in the previous week were more likely to consume these foods on a greater number of days, compared with those reporting no exposure to this marketing in the past week. Reporting exposure to digital marketing of desserts/sweet treats every day or more than once a day was associated with more frequent consumption of desserts/sweet treats. Province of residence (Ontario/Quebec) and total daily time spent online predicted more frequent consumption of fast food, sugary drinks, salty/savoury snacks, and desserts/sweet treats. Overall, more frequent self-reported exposure to digital marketing of unhealthy foods is associated with more frequent consumption of these foods by Canadian youth. Regulations are needed to help protect youth from digital food marketing, which may help reduce their unhealthy food consumption.

Screen time and obesity prevalence in adolescents: an isotemporal substitution analysis

BACKGROUND

We examined the associations between screen time and adolescent obesity and the associations of reallocating screen time to other activities using isotemporal substitution models. Understanding the association between screen time and obesity may provide additional insights into effective obesity prevention strategies in adolescents.

METHODS

We conducted a cross-sectional analysis of 5,180 adolescents (4th and 7th grade students) from the Korean Children and Youth Panel Survey 2018. Participants reported their height, weight, and average time spent watching television, using computer, using smartphone, and other after-school activities. Obesity was defined as BMI-for-age and -sex ≥ 95th percentile based on the 2017 Korean National Growth Charts. We performed multivariable logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between screen time and obesity prevalence, adjusting for potential confounders.

RESULTS

Prolonged smartphone use (≥ 180 vs. <60 m/d: OR [95% CI] = 2.75 [2.06, 3.68]) was associated with a higher obesity prevalence. Television watching (≥ 120 vs. <60 min/d) was positively associated with obesity prevalence among 4th grade students (2.09 [1.51, 2.89]) but the association was not observed among 7th grade students (0.97 [0.63, 1.49]). One-hour increments of any non-screen time activities, with a simultaneous 1-hour decrease in combined screen time, were associated with a lower obesity prevalence (physical activity: 0.75 [0.65, 0.85]; sleeping: 0.69 [0.62, 0.78]; hanging out with friends: 0.80 [0.71, 0.89]; reading: 0.82 [0.69, 0.97]; studying: 0.84 [0.78, 0.90]; chatting with parents: 0.89 [0.88, 0.98]).

CONCLUSIONS

Our data suggest that public health strategies that reduce screen time and increase time for non-screen time activities, such as physical activity, may be effective in lowering adolescent obesity prevalence.

Recreational screen time and obesity risk in Korean children: a 3-year prospective cohort study

BACKGROUND

Studies have shown that prolonged television watching increases obesity risk among children. However, few studies examined the associations with other types of screen time, such as computer and smartphone use, using a prospective cohort study design. Further, little is known about the specific non-screen time activity that may yield the most benefits when reallocating screen time to other activities.

METHODS

We conducted a prospective cohort analysis using 3-year follow-up data from the Korean Children and Youth Panel Survey 2018 (n = 2,023; 4th grade elementary students who were not obese at baseline). Average time spent watching television, using computer and smartphone, and other after-school activities were self-reported at baseline. Weight and height were also self-reported at baseline and follow-up surveys through 2021. We performed multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between screen time and obesity incidence, adjusting for potential confounders. We also performed isotemporal substitution models to examine the associations of reallocating screen time to other non-screen time activities (physical activity, sleeping, hanging out with friends, reading, studying, and chatting with parents) in an equal time-exchange manner.

RESULTS

Longer combined screen time (≥ 240 vs. <120 m/d) was statistically significantly associated with an increased obesity risk (OR [95% CI] = 1.68 [1.03, 2.73]). The direction of associations with television watching (≥ 180 vs. <60 m/d: OR [95% CI] = 2.86 [1.58, 5.20]), computer use (≥ 120 vs. <60 m/d: 1.38 [0.52, 3.64]), and smartphone use (≥ 180 vs. <60 m/d: 1.42 [0.76, 2.65]) were all positive, although the association was most apparent and statistically significant for television watching only. The associations did not change after additional adjustment for other lifestyle factors, including physical activity, sleep, and breakfast skipping. In the isotemporal substitution models, reallocating 1-hour of screen time to reading (OR [95% CI] = 0.67 [0.48, 0.93]) was associated with a decreased obesity risk. Reallocating 1-hour of screen time to physical activity was only marginally significantly associated with obesity risk (0.79 [0.62, 1.01]).

CONCLUSIONS

Our data suggest that more efforts should focus on reducing screen time and increasing time for other non-screen time activities, particularly reading, for obesity prevention in children.

Food-Related Online Media (Mukbang and Cookbang) Exposure and Dietary Risk Behaviors in Korean Adolescents

BACKGROUND

Studies have shown that prolonged smartphone use is associated with dietary risk behaviors among adolescents. However, little is known about whether the exposure to food-related online media contents, such as mukbang (eating broadcast) and cookbang (cooking broadcast), is associated with unhealthy dietary behaviors, independent of overall duration of smartphone use.

OBJECTIVES

This study investigated the associations between the frequency of mukbang/cookbang watching and dietary risk behaviors among Korean adolescents, using nationally representative survey data.

METHODS

In this cross-sectional study, we examined the data from 50,044 middle and high school students in the Korea Youth Risk Behavior Web-based Survey 2022. Participants reported their frequency of mukbang/cookbang watching, mean duration of smartphone use, frequency of breakfast eating, frequency of nighttime eating, and intakes of fast foods, sugar-sweetened beverages (SSBs), and high-caffeine drinks. We performed multivariable logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between mukbang/cookbang watching and dietary risk behaviors, accounting for complex survey sampling and adjusting for potential confounders.

RESULTS

Frequent mukbang/cookbang watching (≥5 times/wk compared with never) was positively associated with dietary risk behaviors, including frequent breakfast skipping (OR: 1.20; 95% CI: 1.13, 1.28), frequent nighttime eating (OR: 1.43; 95% CI: 1.33, 1.54), and frequent intakes of fast foods (OR: 1.69; 95% CI: 1.58, 1.80), SSBs (OR: 1.47; 95% CI: 1.30, 1.66), and high-caffeine drinks (OR: 1.41; 95% CI: 1.33, 1.50), adjusting for duration of smartphone use. All mukbang/cookbang viewers, including those who perceived that mukbang/cookbang videos had "no influence" on their dietary behavior, had higher prevalence of dietary risk behaviors than nonviewers (perceived "no influence" compared with nonviewers-OR: 1.18; 95% CI: 1.10, 1.26, breakfast skipping; OR: 1.15; 95% CI: 1.06, 1.24, nighttime eating; OR: 1.40; 95% CI: 1.30, 1.50, fast foods; OR: 1.22; 95% CI: 1.07, 1.38, SSBs; OR: 1.28; 95% CI: 1.20, 1.37, high-caffeine drinks).

CONCLUSIONS

Our findings suggest that frequent mukbang/cookbang watching may be associated with unhealthy dietary behaviors among Korean adolescents.

Associations of Contemporary Screen Time Modalities With Early Adolescent Nutrition

OBJECTIVE

To determine the associations between screen time across several contemporary screen modalities (eg, television, video games, text, video chat, social media) and adherence to the Mediterranean-DASH (dietary approaches to stop hypertension) intervention for neurodegenerative delay (MIND) diet in early adolescents.

METHODS

We analyzed data from the Adolescent Brain Cognitive Development study of 9 to 12-year-old adolescents in the United States. Multiple linear regression analyses examined the relationship between self-reported screen time measures at baseline (year 0) and the 1-year follow-up (year 1) and caregiver-reported nutrition assessments at year 1, providing a prospective and cross-sectional analysis. Cross-sectional marginal predicted probabilities were calculated.

RESULTS

In a sample of 8267 adolescents (49.0% female, 56.9% white), mean age 10 years, total screen time increased from 3.80 h/d at year 0 to 4.61 h/d at year 1. Change in total screen time from year 0 and year 1 was associated with lower nutrition scores at year 1.

PROSPECTIVE

Screen time spent on television, video games, and videos at year 0 was associated with lower nutrition scores at year 1. Cross-sectional: Screen time spent on television, video games, videos, texting, and social media at year 1 was associated with lower MIND diet scores at year 1.

CONCLUSIONS

Both traditional (television) and several contemporary modalities of screen time are associated, prospectively and cross-sectionally, with lower overall diet quality, measured by the MIND diet nutrition score, in early adolescents. Future studies should further explore the effect of rising digital platforms and media on overall adolescent nutrition.

The Relationship Between Fast Food Consumption and Daily Lifestyle Changes During School Closures Following the COVID-19 Pandemic: A Cross-Sectional Study Among Adolescents in Korea

OBJECTIVE

Increased fast food consumption can have adverse effects on health and well-being among adolescents, posing a significant public health concern. The school closures due to the coronavirus disease-2019 (COVID-19) pandemic have led to changes in eating patterns and disrupted a balance diet among adolescents. This study explored the factors associated with fast food consumption among adolescents during school closures due to the COVID-19 pandemic.

METHODS

A total of 1,710 middle and high school students in Gwangju, South Korea participated in a cross-sectional survey. The self-administered questionnaire included items assessing dietary intake, physical activity, sleep, media use, and sociodemographic information. The Patient Health Questonnaire-9, Generalized Anxiety Disorder-7, and three item version of the UCLA Loneliness Scale were also administered. Multivariable logistic regression was used to examine the factors associated with increased fast food consumption.

RESULTS

Approximately 34.6% of the surveyed adolescents reported increased fast food consumption during school closures, as well as increased sleep duration, increased sedentary behaviors including watching TV and using the internet, and reduced physical activity. Multivariable logistic regression analysis revealed that fast food consumption during school closures was associated with irregular patterns of main meals and sleep, decreased physical activity, increased internet use, and a lack of daytime adult supervision.

CONCLUSION

Our results highlight the need for dietary and lifestyle monitoring and guidelines to promote health among adolescents, especially during school closures. In conclusion, nutrition intervention programs aiming to limit fast food consumption and enhance healthy dietary habits among adolescents during long-term school closures are warranted.

Sedentary Activities and Food Intake among Children and Adolescents in the Zhejiang Province of China: A Cross-Sectional Study

BACKGROUND

Sedentary behavior may affect the types of food consumed in children and adolescents' daily diets. Previous published studies are limited to local surveys. This study aimed to explore the relationship between sedentary behavior and food intake among children and adolescents.

METHODS

A stratified sampling technique was employed in the present cross-sectional study. Demographic characteristics, sedentary behavior, transportation modes, and food intake were investigated.

RESULTS

We found that children and adolescents who watched movies or TV programs online or on their smartphones on weekends and who chatted online on weekends, including on QQ (an instant messaging software service) and WeChat (an instant messaging software service), increased their intake of instant noodles and fried pasta (Spearman's rho = 0.468, 0.575, 0.465, and 0.323; p < 0.05). Children and adolescents who chatted online on weekends, including on QQ and WeChat, increased their intake of tofu skin (Spearman's rho = 0.461; p < 0.05), and those who browsed online on weekdays increased their intake of whole-fat liquid milk (Spearman's rho = 0.455; p < 0.05). Children and adolescents who browsed and chatted online on weekends, including on QQ and WeChat, and who played computer or smartphone games, increased their intake of fried potato chips (French fries or other fried snacks) (Spearman's rho = 0.568, 0.270, and 0.412; p < 0.05). With respect to modes of transportation used to travel to and from school, children and adolescents who took buses and subways increased their intake of rice, instant noodles, sweet potatoes, soybean milk, tofu skin, processed meat products (sausage, ham sausage, or lunch meat), fish, shrimp, vegetables, nuts, and sweet cookies (buns, cakes, Dim sum, and moon cakes) (Spearman's rho = 0.394, 0.536, 0.630, 0.408, 0.485, 0.441,0.410, 0.424, 0.444, 0.541, and 0.366; p < 0.05).

CONCLUSIONS

Sedentary behavior affects the types of food consumed in children and adolescents' daily diets. Children and adolescents who browsed online on weekdays increased their intake of whole-fat liquid milk, but also increased their intake of foods with high fat, high salt, and low nutrient density. Children and adolescents taking buses and subways increased their intake of low-nutrition quality products. Public awareness efforts should focus on reducing the consumption of low-nutrition quality products and nutritional education.

Physical activity, sedentary behavior and pancreatitis risk: Mendelian randomization study

BACKGROUND

Although observational studies have shown that physical activity is a protective factor for acute pancreatitis, the causal associations between PA/ sedentary behavior and acute pancreatitis (AP) and chronic pancreatitis (CP) remain unclear.

METHODS

We used Mendelian randomization as a strategy to assess the causalities between exposures and outcomes by simulating randomized experiments with genetic variation. The collected genetic variants data of physical activity were from UK Biobank, the data on sedentary behavior were also from UK Biobank, and both of them could be found in the GWAS catalog, and the data on AP and CP were from FinnGen. There were three physical activity related activity patterns (moderate to vigorous physical activity [MVPA], accelerometer-based physical activity with average acceleration, [AccAve] and accelerometer-based physical activity with accelerations >425 milli-gravities, [Acc425]) and three sedentary behavior-related lifestyle patterns (Leisure screen time [LST], Sedentary commuting, Sedentary behavior at work). We used inverse variance weighted (IVW), weighted median and MR-Egger for the analysis of Mendelian randomization, followed by sensitivity tests with the Cochran Q test, MR-Egger intercepts analysis and MR-PRESSO.

RESULTS

A causal relationship was found between LST and acute pancreatitis based on IVW analysis (odds ratios [OR] = 1.38, corresponding 95% confidence intervals [CI] = 1.16-1.64, p = 0.0002) and there were no causal relationships between physical activity/sedentary behavior and chronic pancreatitis. Sensitivity analysis showed no pleiotropy and heterogeneity of the results.

CONCLUSIONS

Results show that reducing LST contributes to the prevention of acute pancreatitis, thereby reducing the health burden associated with it.

Genetic associations of leisure sedentary behaviors and the risk of 15 site-specific cancers: A Mendelian randomization study

BACKGROUND AND AIMS

Leisure sedentary behavior (LSB) is associated with the risk of cancer, but the causal relationship between them has not been clarified. The aim of this study was to assess the potential causal association between LSB and risk of 15 site-specific cancers.

METHODS

The causal association between LSB and cancer were assessed with univariate Mendelian randomization (UVMR) and multivariate Mendelian randomization (MVMR). 194 SNPs associated with LSB (from the UK Biobank 408,815 individuals) were adopted as the instrument variables. Sensitivity analyses were performed to ensure the robustness of the results.

RESULTS

UVMR analysis revealed that television watching significantly increased the risk of endometrial cancer (OR = 1.29, 95% CI = 1.02-1.64, p = 0.04) (mainly the endometrioid histology [OR = 1.28, 95% CI = 1.02-1.60, p = 0.031])，breast cancer (OR = 1.16, 95% CI = 1.04-1.30, p = 0.007) (both ER+ breast cancer [OR = 1.17, 95% CI = 1.03-1.33, p = 0.015], and ER- breast cancer [OR = 1.55, 95% CI = 1.26-1.89, p = 2.23 × 10^-5 ]). Although causal association was not found between television watching and ovarian cancer, it was seen in low grade and low malignant potential serous ovarian cancer (OR = 1.49, 95% CI = 1.07-2.08, p = 0.018). However, significant results were not obtained in the UVMR analysis between driving, computer use and the 15 types of cancer. Further MVMR analysis indicated that the above results are independent from most metabolic factors and dietary habits, but mediated by educational attainment.

CONCLUSION

LSB in form of television watching has independent causal association with the risk of endometrial cancer, breast cancer, and ovarian cancer.

The Mediating Effects of Food Content Watching Motivation on the between Watching Time and Nutrition Quotient of Adolescents in Seoul, Korea

Food-related content varies widely and is increasingly popular. Using various media, teenagers can easily access food content, which could affect they eating habits. This study was conducted to confirm the effects of watching motivation on the relationship between food content watching time and eating habits among adolescents in Seoul, Korea. Exactly 806 participants were surveyed about their food content watching status, including watching time and watching motivation. The Nutrition Quotient for adolescents (NQ-A) questionnaire was used to confirm eating habits. Exploratory factor analysis was conducted to classify watching motivation’s subfactors. A parallel multimedia model was used to analyze the effect of watching motivation on the relationship between food content watching time and eating habits. As a result of this study, following the factor analysis, watching motivation was classified into information acquisition, emotional satisfaction, and enjoyment. The influence of food content watching time on NQ-A scores through information acquisition motivation was positively significant, whereas that through emotional satisfaction motivation was negatively significant. Enjoyment motivation did not indirectly affect the relationship between food content watching time and NQ-A scores. Hence, attention should be paid to these mediating factors when analyzing the relationship between watching food-related content and eating habits. Developing and distributing content that meets viewing motivations should help improve adolescents’ eating habits.

Smartphone Usage Patterns and Dietary Risk Factors in Adolescents

BACKGROUND

Whereas earlier studies have shown that traditional screen time such as TV watching influences dietary behaviors in adolescents, little is known about the effects of modern screen time such as smartphone use.

OBJECTIVES

We examined the associations of smartphone usage duration and content type with dietary risk factors among adolescents.

METHODS

We conducted a cross-sectional analysis using a nationally representative sample of 54,601 middle- and high-school students (aged 12-18 y; 26,928 boys and 27,673 girls) in the Korea Youth Risk Behavior Web-Based Survey 2017. Smartphone use (average duration and most frequently used content type) and dietary intakes [frequent breakfast skipping; less frequent intakes of fruits and vegetables; more frequent intakes of instant noodles, fast food, chips/crackers, and sugar-sweetened beverages (SSBs)] were self-reported via an online-based questionnaire. Multivariable logistic regression was performed to estimate ORs and 95% CIs for the associations of smartphone usage duration and content type with prevalence of dietary risk factors, adjusting for potential confounders. All analyses accounted for complex survey sampling.

RESULTS

Prolonged smartphone use (≥300 compared with 1-59 min/d) was associated with (OR; 95% CI) higher prevalence of frequent breakfast skipping (1.60; 1.45, 1.76); frequent intakes of instant noodles (1.65; 1.47, 1.84), fast food (1.36; 1.20, 1.53), and SSBs (1.92; 1.75, 2.11); and less frequent intakes of fruits (1.44; 1.30, 1.59) and vegetables (1.32; 1.18, 1.47). Adjusting for usage duration, using smartphones mainly for messenger/e-mail, social networking service (SNS)/forum, and games were associated with less frequent intakes of fruits (OR: 1.21; 95% CI: 1.12, 1.31; OR: 1.28; 95% CI: 1.17, 1.40; and OR: 1.20; 95% CI: 1.10, 1.32, respectively) and vegetables (OR: 1.24; 95% CI: 1.12, 1.37; OR: 1.26; 95% CI: 1.13, 1.40; and OR: 1.25; 95% CI: 1.12, 1.40, respectively) than was using smartphones for education/information search. Using smartphones mainly for messenger/e-mail (OR: 1.24; 95% CI: 1.14, 1.35) and SNS/forum (OR: 1.18; 95% CI: 1.08, 1.29) were also associated with more frequent intake of SSBs.

CONCLUSIONS

Our data suggest that both duration and content type of smartphone use are independently associated with dietary risk factors among adolescents.

The effect of leisure boredom and A1C level on diabetes eating problems in adolescents with type 1 diabetes

PURPOSE

Eating out of boredom, the changes in daily routine, physical inactivity and longer exposure to screens have made glycemic control difficult at home during the COVID-19 pandemic among adolescents with Type 1 Diabetes Mellitus. Adolescents with diabetes are at higher risk of developing eating problems than are their healthy peers. The aim of this study is to examine the effects of leisure time boredom and A1C level on eating problems in adolescents with Type 1 Diabetes Mellitus.

DESIGN AND METHODS

A descriptive, correlational, and cross-sectional design was used in this study. The study was conducted in Turkey, with the participation of 173 adolescents diagnosed with Type 1 Diabetes Mellitus. Convenience sampling was used to recruit patients from pediatric endocrinology outpatient clinics of hospitals.

RESULTS

It was determined that the diabetes eating problems of adolescents with Type 1 Diabetes were mostly affected by the level of leisure time and A1C, respectively. In the overall model, 58% (F = 4119.701, p < .001) of the factors affecting diabetes eating problems could be explained by the level of leisure boredom and A1C level.

CONCLUSION

It has been found that the adolescents with diabetes with high A1C levels and who cannot use their leisure time and have boredom are more at risk in terms of diabetes eating problems.

PRACTICE IMPLICATIONS

It should be determined how the adolescents with diabetes spend their lesiure time by diabetes health care team, which should be supported to develop leisure time skills. Effective use of leisure time and strategies to cope with boredom should also be included in diabetes education.

Social Media and Children's and Adolescents' Diets: A Systematic Review of the Underlying Social and Physiological Mechanisms

The association between social media (SM) and children's and adolescents' diet is poorly understood. This systematic literature review aims to explore the role of SM in children's and adolescents' diets and related behaviors, considering also the underlying mechanisms. We searched Medline, Scopus, and CINAHL (2008-December 2021) for studies assessing the relation of SM exposure with food intake, food preference, dietary behaviors, and the underlying mechanisms (e.g., brain activation to digital food images-as proxy for SM food images) among healthy children and adolescents aged 2-18 y. A total of 35 articles were included. Of 4 studies, 1 found that exposure to peers' videos on healthy eating, but not SM influencers', increased vegetable intake. Most studies reported that SM was associated with skipping breakfast, increased intake of unhealthy snacks and sugar-sweetened beverages, and lower fruit and vegetable intake, independent of age. Children and adolescents exposed to unhealthy compared with healthy digital food images showed increased brain response in reward- and attention-related regions. The mechanisms underpinning the abovementioned associations were 1) physiological (appetitive state, increased neural response to portion size and energy density of food depicted) and 2) social (food advertising via SM influencers and peers). SM exposure leads to unfavorable eating patterns both in children and adolescents. The identified mechanisms may help tailor future health interventions. Downregulating SM advertising and limiting SM exposure to children and adolescents may improve food intake and subsequent health outcomes. The protocol of this review was registered in PROSPERO as CRD42020213977 (https://www.crd.york.ac.uk/prospero/).

Breakfast Habits and Associations with Fruit and Vegetable Intake, Physical Activity, Sedentary Time, and Screen Time among Swedish 13-14-Year-Old Girls and Boys

This study explored whether breakfast habits were associated with intake of fruits and vegetables, minutes in moderate-to-vigorous physical activity (MVPA), minutes spent sedentary, and screen time among adolescents. Cross-sectional data were collected among 13–14-year-old boys and girls (n = 1139). Breakfast habits and screen time were determined via questionnaire, fruit and vegetable intake were determined through dietary recall, and physical activity and sedentary time were determined via accelerometers. Multilevel mixed models and general estimation equation models were applied. Almost 40% of participants skipped breakfast at least one day of the week. Participants with irregular breakfast habits on weekdays had lower fruit and vegetable consumption by 26.7 g (95% CI = −49.3, −5.9) while irregular breakfast habits during the whole week were associated with higher levels of screen time (OR = 1.5, 95% CI = 1.1, 2.1) compared to regular breakfast habits. Girls with irregular breakfast habits on weekdays had 7.7 min more sedentary time (95% CI = 0.8, 15.7) than girls with regular breakfast habits, while the opposite was found in boys (β = −13.3, 95% CI = −25.3, −2.6)). No significant associations were found for MVPA. Regular breakfast habits should be encouraged, as they might contribute to a higher intake of fruit and vegetables and are associated with lower levels of screen time, although further studies are necessary to establish causation.

Nutritional Behaviors, Health Literacy, and Health Locus of Control of Secondary Schoolers in Southern Poland: A Cross-Sectional Study

Nutritional behaviors remain an essential part of a healthy lifestyle. It seems obvious that unfavorable health behaviors adopted in adolescence are maintained late in adulthood and may have a profound effect on health status. The main aim of this study was to assess the association between nutritional behaviors and health literacy (HL), health locus of control (HLC), and socioeconomic variables in secondary school pupils from a voivodship (the main unit of territorial division) in southern Poland. The analysis was based on dataTable from a paper-and-pencil survey taken by 2223 pupils from schools selected as the result of cluster sampling. The survey questionnaire encompassed a set of five items asking about dietary patterns and the consumption of fruit and vegetables as well as fast food, a European Health Literacy Project Questionnaire consisting of 47 items, the Multidimensional Health Locus of Control (MHLC) scale, and items asking about sociodemographic and economic variables. Uni- and multivariate logistic regression models have been developed to assess the predictors of indicator nutrition behaviors. The adjusted models revealed that internal HLC was not significantly associated with any of analyzed nutritional behaviors. “Powerful other HLC” and “Chance HLC” (dimension of external HLC) were significant predictors of the selected dietary patterns. Furthermore, higher HL was associated with higher consumption of fruit and vegetables [odds ratio, 95% confidence interval (OR, 95% CI)]: 1.02 (1.01–1.04) and with lower consumption of fast food (OR, 95% CI, 0.98, 0.95–0.999). There was a significant relationship between gender, the size of the household, self-assessed economic situation, expenditures on mobile phones, and weekly duration of Internet use and selected nutrition behaviors. In conclusion, developed regression models confirmed a significant relationship between HL and the types of consumed food, but not with dieting patterns. Contrary to earlier studies, internal HLC was not associated with nutrition behaviors. In our study, boys showed more favorable nutritional behaviors than girls. More intense use of the Internet was associated with less beneficial nutritional behaviors. This study brings important results that should have an impact on health promotion interventions addressed to adolescents in southern Poland.