Association between unhealthy dietary behaviors and sleep disturbances among Japanese adolescents: a nationwide representative survey

Short Sleep Duration and Skipping Main Meals among University Students

Introduction  Admission to university influences lifestyle behaviors and is marked by a daily routine of accumulation of activities that can interfere with sleep duration, affecting food choices and meal consumption habits throughout the day. Objective  To analyze the association between short sleep duration and skipping main meals among university students. Materials and Methods  We conducted a cross-sectional study with 1,608 university students aged between 16 and 25 years, who were enrolled in full-time undergraduate courses at a public university in the Midwestern region of Brazil. Information on skipping breakfast, lunch, and dinner was collected through the question "On average, how often do you eat the following meals?". Given the lack of a uniform criterion to define "skipping a meal", in the present study, any answer that did not correspond to the daily consumption of the meal was classified as meal skipping, based on the recommendation of the Dietary Guidelines for the Brazilian Population. Short sleep duration was determined according to sleep time during the night (≤ 6 hours for those aged ≥18 years and ≤ 7 hours for those under 18 years of age). Associations were estimated using adjusted Poisson regression models. Results  The prevalences of skipping breakfast, lunch, and dinner were of 51.0%, 13.9%, and 35.6% respectively. Short sleep duration was observed in 27.2% of the study population. After adjusting for confounding variables, short sleep duration was positively associated with skipping breakfast (adjusted prevalence ratio [PRadj] = 1.20; 95% confidence interval [95%CI] = 1.08-1.34) and skipping lunch (PRadj = 1.64; 95%CI = 1.27-2.12). Conclusion  University students presented a high prevalence of skipping main meals. Short sleep duration was directly associated with skipping two major meals of the day: breakfast and lunch.

Associations of nutrition education with diet quality indexes and chronotype: a cross-sectional study

This study examined the impact of nutrition education on chronotype, sleep quality, and dietary quality among university students. Participants included 317 students with nutrition education and 280 without. Data were collected through questionnaires assessing demographic characteristics, chronotype (using the Morning-Evening Questionnaire), sleep quality (via the Pittsburgh Sleep Quality Index), and dietary habits. Anthropometric measurements and 24-hour food recalls were also recorded. Dietary quality was evaluated using the Healthy Eating Index (HEI)-2020, while dietary fat and carbohydrate quality were assessed with the Fat Quality Index (FQI) and Carbohydrate Quality Index (CQI), respectively. Results indicated that students who received nutrition education had significantly lower body weight, height, and waist circumference compared to those without. Of the students, 8.9% had a morning, 7% had an evening and the rest had an intermediate chronotype. HEI-2020, CQI, and FQI scores were significantly higher in the nutrition education group. Although no significant relationship was found between nutrition education and chronotype, improved dietary and sleep quality were observed in the group with education. This suggested that enhancing nutritional knowledge can positively impact health by improving dietary quality and sleep.

Using the Person-Based Approach to Co-Create and Optimize an App-Based Intervention to Support Better Sleep for Adolescents in the United Kingdom: Mixed Methods Study

BACKGROUND

Poor sleep is a common problem in adolescents aged 14 to 18 years. Difficulties with sleep have been found to have a bidirectional link to mental health problems.

OBJECTIVE

This new research sought to involve young people in the co-creation of a new app, particularly those from underserved communities. The Sleep Solved app uses science-based advice to improve sleep-related behaviors and well-being. The app was developed using the person-based approach, underpinned by the social cognitive theory and the social-ecological model of sleep health.

METHODS

Young people (aged 14-18 y) were recruited from across the United Kingdom to contribute to patient and public involvement (PPI) activities. In partnership with our peer researcher (MHJ), we used a multitude of methods to engage with PPI contributors, including web-based workshops, surveys, think-aloud interviews, focus groups, and app beta testing.

RESULTS

A total of 85 young people provided PPI feedback: 54 (64%) young women, 27 (32%) young men, 2 (2%) genderfluid people, 1 (1%) nonbinary person, and 1 (1%) who reported "prefer not to say." Their levels of deprivation ranged from among the 40% most deprived to the 20% least deprived areas. Most had self-identified sleep problems, ranging from 2 to 3 times per week to >4 times per week. Attitudes toward the app were positive, with praise for its usability and use of science-based yet accessible information. Think-aloud interviews and a focus group identified a range of elements that may influence the use of the app, including the need to pay attention to language choices and readability. User experiences in the form of narrated audio clips were used to normalize sleep problems and provide examples of how the app had helped these users.

CONCLUSIONS

Young people were interested in using an app to better support their sleep and mental health. The app was co-created with strong links to theory- and evidence-based sleep hygiene behaviors. Future work to establish the effectiveness of the intervention, perhaps in a randomized controlled trial, would provide support for potential UK-wide rollout.

Impact of Medical School on the Relationship between Nutritional Knowledge and Sleep Quality-A Longitudinal Study of Students at Wroclaw Medical University in Poland

The aim of this study was to investigate the impact of the first year of medical school on the relationship between nutritional knowledge and sleep. To achieve this, first-year medical students at Wroclaw Medical University were invited to participate in the study during both the initial and final months of their first academic year. The study included 570 students in the initial period and 705 in the latter. The research questionnaire comprised the KomPAN, assessing nutritional knowledge, and the Pittsburgh Sleep Quality Index (PSQI), evaluating sleep quality. The majority of students demonstrated at least sufficient nutritional knowledge, while approximately two-thirds of students experienced poor sleep in both periods. Notably, sleep quality further deteriorated in the second period (PSQI total score: 6.86 vs. 7.38, p = 0.0157). This change was influenced mainly by a decrease in sleep duration and an increase in the use of sleep medications (both p < 0.0001). The significant difference in overall sleep quality between different nutritional knowledge levels emerged only in the second semester, where students with the highest nutritional knowledge slept the best, while those with the lowest slept the worst (p = 0.0001). Crucially, in both periods, the use of sleep medications was highest among individuals with insufficient nutritional knowledge. Throughout the academic year, the usage increased for all except those with the highest nutritional knowledge, who exhibited the best sleep (p < 0.0001). The escalating use of sleep medications among medical students warrants greater attention, and leveraging the relationship between nutritional knowledge and sleep could prove beneficial, as positive habits in one domain may positively influence the other.

Associations between food insecurity and Sleep Duration, Quality, and Disturbance among older adults from six low- and middle-income countries

OBJECTIVES

Although food insecurity has been associated with poor sleep outcomes in young and middle-aged adults, few studies have examined this relationship in older adults. This study aimed to examine the relationship between food insecurity and sleep duration, quality, and disturbance among older adults in six low-income countries (LMICs).

DESIGN AND SETTING

We analyzed nationally representative cross-sectional data from 33,460 adults (≥50 years) from the Study on global AGEing and adult health (SAGE).

MEASUREMENTS

Food insecurity (FI) was assessed using two questions regarding the frequency of eating less and hunger caused by a lack of food. Sleep outcomes included self-reported sleep duration, sleep quality, and sleep disturbances (difficulty falling asleep, frequent sleep interruptions, and early awakening) assessed based on self-reports over two nights. Multivariable logistic regression was used to assess country-specific relationships between food insecurity and sleep outcomes, and random-effects models were used to estimate pooled associations.

RESULTS

The prevalence of FI among older adults in the overall population was 16.2%. In pooled analyses, FI was significantly associated with long sleep duration ≥ 9 h (OR=1.58, 95% CI: 1.30 to 1.93; P=0.001). There were also significant pooled associations between FI and poor sleep quality (OR=1.34, 95% CI: 1.14 to 1.56; P < 0.001) and sleep disturbances (OR=1.44, 95% CI: 1.08 to 1.91; P = 0.014).

CONCLUSIONS

In conclusion, the current study found that FI is adversely associated with sleep duration, quality and disturbances in older adults, with some heterogeneity by country. The findings suggest food policies and intervention programs are needed for vulnerable households.

Nutrient intake, alcohol consumption, emotional eating and anxiety in women nursing students

Objective

The aim of the study was to analyze dietary habits, alcohol habits, emotional eating and anxiety in a sample of Spanish nursing students. These students appear to be essential to the field of public health and to teaching their future patients about their own good practices.

Methods

A cross-sectional investigation was conducted. Participants completed the Emotional Eater Questionnaire, the Alcohol Use Disorder Identification Test (AUDIT) test to evaluate alcohol intake, the State-Trait anxiety Inventory (STAI) test to measure levels of anxiety as a state and anxiety as a trait, and self-reported sociodemographic data. Following classroom instruction, three-day food records were used to gauge food intake.

Results

The calorie intake for the macronutrients Ca, Mg, K, and Fe were below the Recommended Dietary Intakes (DRI) and imbalanced. The percentage E of proteins was 132.7 % more than recommended, while the percentage of carbohydrates is below the recommended level. Dietary energy consumption barely equaled 78 % of the total energy consumed by this sex and age group. With respect to emotional eating, nursing women students were low emotional eater (44 %) > emotional eater (30 %) > non-emotional eater (22.7 %). The students' emotional eating is substantially connected with fast food and sweets, or less healthy food intake behaviors. According to the Alcohol Use Disorder Identification Test (AUDIT), 82.7 % of female students used alcohol on a regular basis in a low-risk manner.

Conclusion

The findings demonstrated a link between anxiety and dietary fat intake. Trait anxiety was negatively connected with emotional eating (EE), whereas state anxiety was positively correlated with meat consumption. It is crucial to consider these findings when creating prevention/intervention plans and profiles of harmful eating behaviors.

Intake of ultra-processed foods and sleep-related outcomes: A systematic review and meta-analysis

The aim of this review article was to evaluate the association between the intake of ultra-processed foods and sleep-related outcomes through a systematic review and meta-analysis. Pubmed, LILACS, Scielo, Scopus, Embase, and Web of Science were searched on December 31, 2021, for studies that evaluated the association between ultra-processed foods and sleep-related outcomes (self-reported sleep duration and quality). Pooled odds ratios were assessed through a random-effects model; heterogeneity was evaluated using the I² statistic. Fifteen cross-sectional studies were included; 14 showed that the high intake of ultra-processed foods was statistically significantly associated with sleep-related outcomes (sleep duration and quality). In the crude analysis, compared with low intake, high intake of ultra-processed foods increased the odds of sleep-related outcomes, with increased odds among children and/or adolescents, and null results among adults. When adjusted for cofounders, we found statistically significant results for all ages. The high intake of ultra-processed foods was associated with sleep-related outcomes, with moderate credibility of the evidence. Longitudinal studies and clinical trials confirming these findings are necessary.

The effect of unhealthy dietary habits on the incidence of dental caries and overweight/obesity among Egyptian school children (A cross-sectional study)

Background

Obesity and dental caries are public health problems in Egypt. Factors such as unhealthy diet, poor oral hygiene, and physical inactivity can play a major role in both problems. This study was carried out to illuminate the mutual unhealthy dietary risk factors associated with the incidence of both health conditions.

Methods

Between 1 October 2020 and 1 July 2021, 369 Egyptian children (5-10 years) were examined. Dental status was assessed using decayed, missing/extracted, and filled tooth indices (dmft, deft, and DMFT) for deciduous, mixed, and permanent dentitions, respectively. Moreover, the lifestyle, food habits, and body mass index (BMI) were recorded.

Results

A total of 342 (93.7%) of the included subjects suffered from caries, and only 27(7.3%) were caries-free. Based on BMI percentiles, 247 (66.9%) of the youngsters were overweight/obese, while 122 (33.1%) had normal weight. The mean dmft was 6.9 (±4.6), deft 4.2 (±3.3), and DMFT 0.1 (±1.7). In the primary dentition, a significant positive correlation was detected between dmft and BMI, legumes, sweetened milk and juice, soft drinks, and desserts, while a significant negative correlation was detected between dmft/deft, meat/poultry/fish, fresh fruits, and vegetables. A significant positive correlation was detected between deft and BMI, sweetened milk and juice, ice cream, candies, and crackers. In the permanent dentition, a significant positive correlation was detected between age, soft drinks, sweetened juice, desserts, and DMFT, while a significant negative correlation was detected with fresh fruits and vegetables. BMI was significantly negatively correlated with a healthy lifestyle, meat/poultry/fish consumption, and fresh fruits and vegetables while positively correlated with legumes, ice cream, soft drinks, granulated sugars, desserts, fast food, and caffeinated drinks.

Conclusion

Overweight/obesity was positively correlated with primary dentition dental caries. Desserts (sweetened snacks) and soft drinks could be the common risk factors associated with high caries and overweight/obesity incidence among Egyptian school children; conversely, consumption of fruits and vegetables could hinder both health conditions. Moreover, sweetened juices were associated with primary and permanent dental caries.

Patterns and Associations of Physical Activity, Screen Time, Sleep, and Dietary Habits among Saudi Females Participating in Fitness Centers

This study was designed to investigate the level and associations of physical activity, sedentary behavior, sleep, and dietary habits among Saudi women attending fitness centers in Riyadh. A descriptive cross-sectional study was carried out from 12 fitness centers in Riyadh, Saudi Arabia. A total of 460 participants answered a two-part survey self-administered questionnaire, which included information about the demographic characteristics and lifestyle. The analysis found significant differences between the two groups in terms of age, weight, BMI, and combined prevalence of being overweight and obese. Compared with less active females, high active females showed significantly more favorable dietary habits (p < 0.05). Significantly higher values were observed for the total physical activity energy expenditure in METs-min/week (p = 0.028). Moreover, females with high screen time (>3 h per day) were younger, less active, slept longer, and had higher intakes of fast foods and chocolates/candy intake (p = 0.001). Overall, the participants were highly active, exceeding the recommended physical activity needed to enhance health. The analysis also showed sufficient sleep duration (>7 h/night) was significantly associated with the diet and nutrition of the participants. Health education programs are needed to reduce the risks of sedentary behavior, sleep problems, and dietary habits.

Accumulated unhealthy behaviours and insomnia in Japanese dwellers with and without cardiovascular risk factors: a cross-sectional study

OBJECTIVES

To date, the association between accumulated unhealthy behaviours and insomnia in individuals stratified according to the presence or absence of major cardiovascular risk factors is unclear. This study aimed to examine the effect of accumulated unhealthy behaviours on insomnia in Japanese dwellers.

DESIGN

Cross-sectional study.

SETTING

Baseline data between April 2012 and March 2015.

PARTICIPANTS

Our study used cross-sectional data among Japanese aged 35-74 years in a rural community (N=9565), the attendees of annual municipal or work site health check-up programmes.

MAIN OUTCOME MEASURES

Insomnia was assessed by Athens Insomnia Scale, which was set at 6 points and greater; other scales were given. Participants were categorised into three groups by their number of unhealthy behaviours (no exercise habit, smoking, alcohol drinking, skipping breakfast and obesity): 0-1, 2-3, 4 or more. The association between accumulated unhealthy behaviours and insomnia was estimated by logistic regression analysis. Further analysis was done after stratification of cardiovascular risk factors assessed by anthropometrics and clinical biochemistry measurements.

RESULTS

The overall prevalence of insomnia was 13.3% for men and 19.3% for women. Men with unhealthy behaviour factors were more likely to have insomnia after adjusting for potential confounders, compared with the least unhealthy group (trend p=0.013). Women with four or more unhealthy behaviour factors were more likely to have insomnia, compared with the lowest groups (OR 1.175, 95% CI 1.077 to 1.282). Insomnia has an association with the unhealthy behaviours among men without cardiovascular risk factors (lowest groups: OR 1.133, 95% CI 1.037 to 1.238, trend p=0.026). Women without hypertension were more likely to have suspected insomnia, compared with the lowest group (OR 1.215, 95% CI 1.101 to 1.341).

CONCLUSION

The results showed accumulated unhealthy behaviours were associated with increased risk of insomnia in Japanese dwellers. For healthy population without cardiovascular risk factors, unhealthy behaviours should be considered as background conditions for insomnia.

Care Their Diet and Mind: Association between Eating Habits and Mental Health in Chinese Left-behind Children

Studies have shown that the prevalence of mental health problems is high among left-behind children (LBC). Modifiable eating habits may play an important role in promoting mental health among these adolescents. This study aimed to investigate the situation of dietary habits and their association with mental health problems in a sample of Chinese LBC. We conducted this cross-sectional study in an economically disadvantaged area of China in May 2020. Information on socio-demographic factors, eating habits (the frequency of eating carbohydrates, fruits, vegetables, protein, and breakfast), and mental health problems (insomnia, depression, and anxiety) were collected among local adolescents. Among 8939 adolescents were recruited, a total of 3314 LBC (1455 males and 1859 females, aged 12–17 years) were identified and included in the current study. Associations between dietary habits and mental health were analyzed by generalized linear models. Results indicated that the dietary pattern was unhealthy among LBC and even worse in females. Compared to routinely eating breakfast and fruits, lower frequencies of eating breakfast and fruits were identified as two significant factors with higher risks of mental health problems. Moreover, the association was more pronounced in females. Therefore, improving diet quality, particularly the frequency of eating breakfast and fruit intake may be an effective approach in the mental health promotion for LBC, especially for females.

The association between dietary patterns and quality and duration of sleep in children and adolescents: A systematic review

BACKGROUND

Dietary pattern has been represented as a contributor to the duration and quality of sleep. This study aimed to review the evidence on this relation among children and adolescents.

STUDY DESIGN

This was a systematic review on the association of dietary pattern and sleep.

METHODS

A literature search was conducted for all articles published between 1980 and August 2020 using the terms "diet" AND "sleep" in PubMed/Medline, Scopus, Web of Science, Cochrane, and Embase databases. Screening and selection of eligible studies were performed by two separate investigators. Studies reporting the impact of different dietary patterns and indices on sleep duration or quality were included.

RESULTS

Fourteen publications (12 cross-sectional, 1 cohort, and 1 clinical trial) were identified. Findings from most studies suggested that long sleep duration was consistently associated with healthy dietary patterns, such as "Vegetables & Healthy Proteins", "Traditional", "Fruit & Vegetables", etc. Results were more mixed and inconclusive regarding the quality of sleep, with 2 studies supporting, 2 studies disapproving, and one study neutral about the association between better sleep quality and healthier dietary patterns. The association between diet and sleep seemed to be affected by confounders and covariates, including sex, physical activity, screen time, etc. CONCLUSIONS: Longer sleep duration appears to be associated with healthier dietary pattern. However, various results in regard to the relation between dietary patterns and sleep quality preclude definitive conclusions. Further research with standard measures of sleep quality and experimental study designs are needed to better define the causal relationship between sleep and diet.

Eating habits are associated with subjective sleep quality outcomes among university students: findings of a cross-sectional study

PURPOSE

This study investigated the relationships between eating habits and sleep quality among university students.

METHODS

In a cross-sectional study, university students completed a self-report questionnaire to assess eating habits and meal timing. We assessed subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and examined the associations between eating habits and overall sleep quality and its components.

RESULTS

Four hundred ninety-eight students participated in the study. Students who used to skip breakfast, ate late-night snacks, and replaced meals with snacks were at 1.20 times, 1.24 times, and 1.25 times higher likelihood of having poor overall sleep quality, respectively. Multiple logistic regression analysis showed that skipping breakfast (r =  - 0.111, P = 0.007), late-night snacks (r =  - 0.109, P = 0.007), replacing meals with snacks (r =  - 0.126, P = 0.002), and irregular mealtimes (r =  - 0.094, P = 0.018) were the best correlates with poor sleep quality. After adjustment to demographic variables, replacing meals with snacks followed by skipping breakfast were the best independent associations with poor sleep quality by the PSQI.

CONCLUSIONS

Eating habits and meal timing were significantly associated with sleep quality. We speculate that healthy eating habits may lead to improved sleep quality and sleep components among university students.

Food Insecurity and Sleep Disturbance Among 223,561 Adolescents: A Multi-Country Analysis of Cross-Sectional Surveys

This study was to investigate the association between food insecurity (FI) and sleep disturbance among adolescents. Based on the cross-sectional data of the Global School-based Student Health Survey, this study analyzed self-reported data from adolescents in 68 countries. Multivariate logistic regression and meta-analysis were used to evaluate the association between FI and sleep disturbance. The final sample included 223,561 adolescents. The prevalence of severe FI and sleep disturbance was 6.4% and 8.0%, respectively. Severe FI was significantly associated with a higher risk of sleep disturbance in 48 of the 68 countries after adjusting for covariates, with a pooled OR (95% CI) of 1.94 (1.79-2.09). Overall, the association between FI and sleep disturbance was similar across countries and gender, though a large level of heterogeneity existed across upper- and middle-income countries. Identifying adolescents suffering from FI and remedying the FI severity may be important to improve sleep quality in global adolescents.

The association between internet usage and sleep problems among Japanese adolescents: three repeated cross-sectional studies

STUDY OBJECTIVES

Sleep problems and problematic internet use have important implications for adolescent health; however, there have been no large-scale surveys using comprehensive measures. We examined the association between internet use duration and sleep problems among Japanese adolescents.

METHODS

We used data from the Lifestyle Survey of Adolescents collected in 2012, 2014, and 2017. We calculated the change in sleep status (insomnia, sleep duration, bedtime, and sleep quality) and internet usage (screen time and services such as internet surfing, social media use, streaming such as YouTube, and online gaming). A binary logistic model was estimated for insomnia. Generalized ordered logit models were employed for the ordinal outcomes (sleep duration, bedtime, sleep quality, and multidimensional sleep health). Sampling weights were constructed based on participation rate on survey years and selection rates from population statistics.

RESULTS

We analyzed data from 248,983 adolescents. Sleep status was unchanged; however, many adolescents used more internet services and for longer durations. The odds ratio of internet screen time for all sleep problems (insomnia, shorter sleep duration, later bedtime, and worse sleep quality) gradually declined. Longer internet screen time (> 5 hours) was strongly associated with all sleep problems. Internet services were also associated with sleep problems; particularly, social media use and online gaming were linked to later bedtimes.

CONCLUSIONS

Despite the decreased strength in the association between internet usage and sleep problems, longer internet time was strongly associated with sleep problems. Public health interventions should consider internet use as an intervention target to improve adolescents' health.

Sleep problems and complexity of mental health needs in adolescent psychiatric inpatients

Sleep problems are highly co-morbid with psychiatric disorders and are part of the complex and multiple factors contributing to symptoms and functional disability. The current study aimed to determine how sleep problems in the period preceding psychiatric admission relate to profiles of mental health needs in adolescent inpatients. This retrospective study included 424 adolescents (13-17 years) admitted over a five-year period to an acute crisis stabilization unit in a tertiary care pediatric hospital. Adolescents were divided into two age- and sex-matched groups based on the presence of moderate to severe sleep problems. Profiles of mental health needs were assessed at admission using the Child and Adolescent Needs and Strengths - Mental Health Acute (CANS-MH) and a complexity score was calculated as the total number of actionable CANS-MH items. Results showed a positive association between sleep problems and needs pertaining to eating disturbances, adjustment to trauma, and school attendance. Odds ratios for sleep problems increased progressively as the complexity scores increased, reaching a plateau at six needs beyond which odds ratios remained at their highest level. Adolescents with sleep problems were more likely to undergo medication changes during psychiatric hospitalization and were more likely to be discharged with antipsychotic medication. These findings suggest that sleep difficulties in adolescent inpatients may be associated with distinct and more complex profiles of mental health needs. The evaluation of sleep problems early in the course of psychiatric hospitalization may be an important part of the psychiatric assessment process to inform the global treatment plan.

Gender differences in dietary behaviors among Japanese adolescents

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Few studies assessed a variety of adolescent dietary behaviours in Japan.

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The findings suggest that gender differences existed in dietary behaviors.

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Girls tended to adopt regular dietary behaviors as compared to boys.

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Schools support modeling and reinforcing healthy dietary behaviors.

Unhealthy dietary behaviors in adolescence are an important public health problem. Gender differences in dietary behaviors have already appeared during adolescence. However, few studies have assessed a variety of adolescent dietary behaviors in Japan. We aimed to clarify gender differences in unhealthy dietary behaviors among Japanese adolescents. The participants consisted of 84,988 participants from seventh to 12th grades. Unhealthy dietary behaviors were defined according to the National Health and Nutrition Survey. Multivariable logistic regression was used to analyze a nationally representative sample of Japanese adolescents from the 2014 to 2015 Lifestyle Survey. The effective response rate was 51.4%. The prevalence of unhealthy dietary behaviors (skipping breakfast, snacking, eating out, skipping meals, eating alone at dinner, and subjectively poor diet quality) among boys and girls was 14.2% versus 12.4%, 19.6% versus 14.1%, 10.6% versus 7.0%, 7.9% versus 5.6%, 13.3% versus 12.1%, and 12.3% versus 15.8%, respectively. Compared with boys, girls were more negatively associated with skipping breakfast [OR = 0.76 (95% CI 0.73–0.79)], snacking [OR = 0.67 (95% CI 0.65–0.70)], eating out [OR = 0.62 (95% CI 0.59–0.66)], skipping meals [OR = 0.61 (95% CI 0.58–0.65)], and eating alone at dinner [OR = 0.79 (95% CI 0.76–0.83)]. However, girls were more positively associated with subjectively poor diet quality [OR = 1.19 (95% CI 1.14.1.24)]. The findings suggest that gender differences existed in dietary behaviors. Gender differences in dietary behaviors suggest opportunities for tailoring interventions related to dietary education in schools.

Skipping breakfast, poor sleep quality, and Internet usage and their relation with unhappiness in Japanese adolescents

Subjective happiness is often regarded as a major life goal. Although Japan is an economically powerful country, the level of subjective well-being reported among Japanese adolescents is lower than in other countries. We aimed to investigate the lifestyle factors related to unhappiness in Japanese adolescents. We collected data through the 2017–2018 Lifestyle Survey of Adolescents, a nationally representative cross-sectional study enrolled in randomly selected junior and senior high schools throughout Japan. We assessed the prevalence of subjective unhappiness in junior and senior high school students according to school life factors and daily lifestyle habits. A multivariable logistic regression analysis was used to examine the associations between these factors and unhappiness. A total of 64,329 students were included in the sample (mean age 15.7 years, 53.9% boys). The average prevalence of unhappiness was 10.2%. The logistic regression analyses indicated that unhappiness was strongly associated with being male and with engaging in unhealthy lifestyle behaviors such as not having breakfast, poor sleep quality, and some problematic Internet usage. Although the prevalence of unhappiness was significantly higher among current smokers and alcohol drinkers, these behaviors were not associated with unhappiness in the multivariable logistic regression analysis. Unhappiness among Japanese adolescents appears to be strongly related to how they spend their daily life. We therefore consider it desirable for school officials to educate students on the importance of happiness and lifestyle factors conducive to happiness.

Association between the Degree of Processing of Consumed Foods and Sleep Quality in Adolescents

The aim of this study was to evaluate the association between food consumption by the degree of processing and sleep quality in adolescents from São Luís, Maranhão, Brazil. A cross-sectional study with 2499 adolescents (aged 18 to 19 years) was developed. Exposure variables included energy contributions of food groups stratified by the NOVA classification: fresh or minimally processed foods (FMPF), processed foods (PF), and ultra-processed foods (UPF), categorized into quartiles. The outcome variable was sleep quality assessed with the Pittsburgh Sleep Quality Index. Associations between these variables were estimated by Poisson regression, with robust estimation of variance. Most of the adolescents had poor sleep quality (57.1%). There were associations between FMPF in the third (57.1%-66.0% of total calories; prevalence ratio PR = 0.88; 95% CI: 0.80, 0.97) and fourth quartile (66.1%-95.8% of total calories; PR = 0.87; 95% CI: 0.78, 0.96) and lower prevalence of poor sleep quality. The fourth quartile of UPF (44.3%-81.8% of total calories; PR = 1.14; 95% CI: 1.03, 1.27) was associated with a higher prevalence of poor sleep quality. Higher intake of FMPF is a protective factor for poor sleep quality, whereas higher UPF consumption is a risk factor for poor sleep quality.

The relationship between subjective happiness and sleep problems in Japanese adolescents

OBJECTIVES

Low sleep quality in adolescents is an important public health concern, as it relates to both their current and future physical and mental health. Furthermore, subjective happiness is also often regarded as a major life goal. Although Japan is an economically powerful country, the reported levels of subjective happiness among Japanese adolescents is low. Thus, this study aims to examine the relationship between subjective happiness and sleep problems in Japanese adolescents.

METHODS

We conducted a nationally representative cross-sectional study of adolescents enrolled in junior and senior high schools in Japan. We used a questionnaire to determine the prevalence of sleep problems (eg, insomnia, short sleep duration (SSD) and poor sleep quality) and to evaluate the participants' reported levels of subjective happiness. Multivariable logistic regression analyses were used to examine the associations between subjective happiness and sleep problems. Adjusted variables were basic demographic characteristics (eg, gender and school grade), lifestyle behaviors, and mental health status.

RESULTS

Data from 64,329 students were analyzed (age range 12-18 years, mean age 15.7 years, 53.9% male). The results indicated that reported levels of subjective happiness were strongly associated with the prevalence of sleep problems. Linear relationships can be observed between sleep problems and subjective happiness scores. The multivariable logistic regression analysis showed that dose-response association of subjective happiness score was observed with all three sleep problems.

CONCLUSIONS

Due to these findings, we recommend that policy makers and school officials educate adolescents on the importance of both subjective happiness and good sleep hygiene.