Association between self-reported sleep duration and dietary quality in European adolescents

Effects of Early Wake-Up Time on Obesity in Adolescents

Background: Although numerous studies have reported that obesity in adolescents is related to shorter sleep duration, few studies have reported the effect of sleep timing, particularly early wake-up time, on obesity. Objectives: To investigate the association between wake-up time and adolescent obesity. Methods: Using the Korean National Health and Nutrition Examination Survey VII data, 1301 middle school and high school students were selected and grouped according to BMI. Sleep timing and lifestyle factors were evaluated using self-reported questionnaires. Results: The mean bedtime and wake-up time were 00:09 am and 07:06 am, respectively. Despite similar bedtimes, the group with overweight/obesity woke up earlier than the group with underweight/normal weight. The BMI z-score and the overweight/obesity relative risk decreased as the wake-up time was delayed, even after adjustment for covariates. Participants who woke up before 06:50 am had a 1.82-fold higher risk of having overweight/obesity than those who woke up after 07:30 am. Participants who woke up late tended to sleep longer than those who woke up early. Conclusions: Waking up early is significantly associated with an increased BMI z-score in adolescents and may be a risk factor for overweight/obesity.

The association between self-reported nocturnal sleep duration, irregularity in daily energy intake and diet quality in a sample of Iranian adults

OBJECTIVE

Evidence on the relationship between sleep duration and irregularity in daily energy intake with diet quality in Iranian adults is scarce. We aimed to evaluate the association of sleep duration with diet quality and irregularity in daily energy intake.

DESIGN

This is a cross-sectional study.

SETTING

The study was performed in healthcare centres in Tehran.

PARTICIPANTS

739 adults aged 20-59 years were recruited. Dietary intake was assessed by a FFQ and three 24-h dietary recalls. Diet quality was assessed using the Healthy Eating Index-2015 (HEI-2015). An irregularity score of daily energy intake was calculated based on the deviation from the 3-d mean energy intake. Sleep duration was estimated using self-reported nocturnal sleep duration by each person.

RESULTS

The mean age of the study participants was 44·4 ± 10·7 years; 70 % were women. The mean nocturnal sleep duration, HEI score and irregularity score were 6·7 ± 1·22 h/d, 52·5 ± 8·55 and 22·9 + 19, respectively. After adjusting for potential confounders, sleep duration was not associated with adherence to HEI-2015 (OR: 1·16; 95 % CI 0·77, 1·74). Longer sleep duration was marginally associated with a lower odd of irregularity in daily energy intake. However, after adjustment for various confounders, this association was not significant (OR: 0·82; 95 % CI 0·50, 1·33; Ptrend = 0·45). No significant interaction was observed between sleep duration and irregularity in daily energy intake in relation to adherence to HEI-2015 (Pinteraction = 0·48).

CONCLUSIONS

We found that sleep duration was not associated with adherence to HEI-2015 and irregularity in daily energy intake. Further prospective studies are warranted.

Shorter sleep among adolescents is associated with lower fruit and vegetable consumption the following day

BACKGROUND

Insufficient sleep has been associated with weight gain and metabolic dysregulation, with one suggested mechanism being through reduction in diet quality. Experimental evidence supports a causal effect of sleep timings on diet but this may not be applicable to a free-living adolescent population. In this analysis we use daily measures of sleep timings and diet quality, to examine the effect of sleep duration and timing on diet quality the following day among free-living adolescents.

METHODS

The ROOTS study is a prospective cohort recruited from secondary schools in Cambridgeshire and Suffolk (UK). Participants (n = 815) at mean age 15.0y (SD 0.3y) completed a diet diary and wore a combined heart rate and accelerometer device over 4 consecutive days. Sleep duration and timing (midpoint) were derived from acceleration and heart rate traces, while daily energy density and fruit and vegetable intake were calculated from dietary data. Analyses were performed at day-level (1815 person-days). Multilevel random effects models were used to test associations between sleep each night and subsequent day diet, with daily sleep and diet measures nested within individuals and schools, and adjusted for day-level and individual-level confounding variables.

RESULTS

Adolescents slept a mean of 7.88 hrs (SD 1.10) per night, reporting a mean energy density of 2.12 kcal/g (SD 0.48) and median energy-adjusted daily fruit and vegetable intake of 137.3 g (IQR 130.4). One hour shorter sleep duration was associated with lower intake of fruit and vegetables (-6.42 g, 95%CI -1.84, -10.99) the following day. An association with higher dietary energy density (0.016 kcal/g, 95%CI 0.034, -0.002) the following day was observed but did not reach statistical significance. Sleep timing was not associated with either fruit and vegetable intake (-2.52 g/d, 95%CI -7.66, 2.62) or dietary energy density (-0.001 kcal/g, 95%CI -0.022, 0.020).

CONCLUSIONS

Our observational findings from a free-living adolescent population support the experimental evidence for a causal role of sleep on diet, with shorter sleep duration at night leading to a small decrease in diet quality the following day. These findings support experimental evidence to suggest inclusion of sleep duration as one component of interventions designed to improve diet quality and weight status in adolescents.

Evaluation of Age Based-Sleep Quality and Fitness in Adolescent Female Handball Players

The present study aimed to examine the differences in sleep hygiene, balance, strength, agility, and maximum aerobic speed (MAS) between two groups of female handball players aged under 14 (U14) and under 17 (U17) years. Seventy-two female handball players participated and were divided into two groups according to age: U14 (n = 36, age: 13.44 ± 0.5 years) and U17 (n = 36, age: 15.95 ± 0.76 years). Sleep hygiene was evaluated using three questionnaires: Sleep quality and sleepiness via the Pittsburgh (PSQI) and Epworth (ESS) questionnaires, and the insomnia questionnaire via the measurement of the insomnia severity index (ISI). Physical fitness was evaluated with the stork balance tests with eyes open (OEB) and closed (CEB), the vertical jump (SJ), horizontal jump (SBJ), and five jump (FJT) tests, the agility (t-test) and the maximum aerobic speed (MAS) tests. No significant differences were shown between U14 and U17 players in all PSQI, ISI, and ESS scores, and balance and strength performances. Meanwhile, the U17 players’ performances were significant better in agility quality (p = 0.003 < 0.01) and MAS (p = 0.05) compared to the U14 players. Biological gender specificity during the maturation phase may inhibit the improvement of balance, and strength performances between the age of 13 and 17 years, while agility and MAS performances are more affected by age alterations.

Sleep duration and eating behaviours are associated with body composition in 5-year-old children: findings from the ROLO longitudinal birth cohort study

Inadequate sleep and poor eating behaviours are associated with higher risk of childhood overweight and obesity. Less is known about the influence sleep has on eating behaviours and consequently body composition. Furthermore, whether associations differ in boys and girls has not been investigated extensively. We investigate associations between sleep, eating behaviours and body composition in cross-sectional analysis of 5-year-old children. Weight, height, BMI, mid upper arm circumference (MUAC), abdominal circumference (AC) and skinfold measurements were obtained. Maternal reported information on child's eating behaviour and sleep habits were collected using validated questionnaires. Multiple linear regression examined associations between sleep, eating behaviours and body composition. Sleep duration was negatively associated with BMI, with 1-h greater sleep duration associated with 0·24 kg/m² (B = 0·24, CI -0·42, -0·03, P = 0·026) lower BMI and 0·21 cm lower (B = -0·21, CI -0·41, -0·02, P = 0·035) MUAC. When stratified by sex, girls showed stronger inverse associations between sleep duration (h) and BMI (kg/m²) (B = -0·32; CI -0·60, -0·04, P = 0·024), MUAC (cm) (B = -0·29; CI -0·58, 0·000, P = 0·05) and AC (cm) (B = -1·10; CI -1·85, -0·21, P = 0·014) than boys. Positive associations for 'Enjoys Food' and 'Food Responsiveness' with BMI, MUAC and AC were observed in girls only. Inverse associations between sleep duration and 'Emotional Undereating' and 'Food Fussiness' were observed in both sexes, although stronger in boys. Sleep duration did not mediate the relationship between eating behaviours and BMI. Further exploration is required to understand how sleep impacts eating behaviours and consequently body composition and how sex influences this relationship.

Gender Differences in the Relationships between Perceived Stress, Eating Behaviors, Sleep, Dietary Risk, and Body Mass Index

Background: Obesity is a growing epidemic among university students, and the high levels of stress reported by this population could contribute to this issue. Singular relationships between perceived stress; engagement in restrained, uncontrolled, and emotional eating; sleep; dietary risk; and body mass index (BMI) have been reported in the current body of literature; however, these constructs interact with each other, and the complex relationships among them are infrequently examined. Therefore, the aim of the present study was to explore the complex relationships between these constructs using mediation and moderation analyses stratified by gender. Methods: A cross-sectional study, enrolling university students from the United States (U.S.), the Netherlands, South Korea, Malaysia, Ireland, Ghana, and China, was conducted between October 2020 and January 2021 during the COVID-19 pandemic. Perceived stress; maladaptive eating behaviors including restrained, uncontrolled, and emotional eating; sleep duration and quality; dietary risk; and BMI were assessed using validated questionnaires, which were distributed through an online platform. Results: A total of 1392 students completed the online survey (379 male, 973 female, and 40 who self-identified as “other”). Uncontrolled and emotional eating mediated the relationship between perceived stress and dietary risk for both males and females; higher sleep quality weakened this relationship among female students but not males. Emotional eating mediated the relationship between perceived stress and BMI for both males and females, but higher sleep quality weakened this relationship only among females. Conclusions: Our findings suggest that students in higher education are likely to benefit from interventions to reduce uncontrolled and emotional eating. Programs that improve sleep quality, especially during highly stressful periods, may be helpful.

[Sleep duration, overweight and consumption of ultra-processed foods among adolescents]

The scope of this article is to analyze the relationship between insufficient sleep duration, overweight/obesity and the consumption of ultra-processed foods among adolescents aged 10 to 14 years. This is a cross-sectional study, with an evaluation of 1,384 adolescents from public schools in João Pessoa-PB, participating in the Longitudinal Study on Sedentary Behavior, Physical Activity, Diet and Adolescent Health (LONCAAFS). Sociodemographic variables, sleep duration, class shift, anthropometric nutritional status, sedentary behavior and food consumption were measured. Linear and logistic regression of the following were performed using Stata 13.0 Software: the prevalence of short sleep duration of 29.5% (<9h/night); a significant association between short sleep duration and excess weight only for adolescents <12 years old. With respect to the relationship between sleep duration and the consumption of ultra-processed foods, the longer the sleep duration, the lower the consumption of snacks by adolescents under 12 years old, with a positive association for ≥12 years old only with adjustment by the physical activity variable. There was no association with the "sugary drinks" and "cookies" groups for any of the age groups analyzed.

Methodological Aspects of Diet Quality Indicators in Childhood: A Mapping Review

Diet quality indicators (DQIns) are tools that aim to assess an individual's overall diet quality. Previous reviews focused mainly on health-related outcomes but did not provide detailed information about components, assessment variables, or important methodological issues for the development and application of DQIns in the pediatric age. The current mapping review aims to provide comprehensive guidance regarding DQIns developed through a priori methodology in children aged ≤14 y that have been applied worldwide. A mapping review was conducted, whereby 1665 original articles describing the development, modifications, and updates of DQIns, published up to June 26, 2020, in English and Spanish, were retrieved. A total of 139 articles were identified and classified into 13 subgroups. There were 10 overall DQIns: Healthy Eating Indexes (n = 25), Dietary Diversity Scores (n = 20), Diet Quality Indexes (n = 16), Food Variety Scores (n = 11), Healthy and Unhealthy Scores (n = 11), Feeding and Eating Indexes (n = 10), Diet Quality Scores (n = 5), Nutritional Adequacy and Micronutrients Indexes (n = 5), Dietary Guidelines Indexes (n = 5), and Other Healthy Diet Indexes (n = 13). Three additional subgroups of dietary and lifestyle indicators found were Mediterranean Diet Indexes (n = 10), Diet-Lifestyle Indexes (n = 5), and Breakfast Quality Indexes (n = 3). This compilation of DQIns will help researchers select the most appropriate tool for future epidemiological studies by considering a careful selection of information about the assessment components, scoring methods, and key methodological issues. The main limitations of this review are that, due to its nature, a risk-of-bias assessment was not performed and the article screening was completed in 2 databases (PubMed/MEDLINE and Scopus). More research is needed to identify health-related outcomes associated with DQIns in the pediatric population, using clearer and more standardized methodological criteria.

Weekend night vs. school night sleep patterns, weight status, and weight-related behaviors among adolescents

OBJECTIVE

In this study, we examine associations between objectively measured weekend night vs. school night sleep patterns, weight status, and weight-related behaviors among adolescents.

DESIGN

Cross-sectional study.

SETTING

Five Minnesota high schools that started early (7:30 or 7:45 AM) in Spring 2016.

PARTICIPANTS

Ninth grade students, ages 14.5-16 years (n = 284).

MEASUREMENTS

Students completed surveys, had body measurements taken, and wore sleep (wrist) actigraphs for 1 week (n = 284). We examined weekend night-school night differences in sleep duration and sleep timing. We then assessed whether these factors were related to weight status and weight-related behaviors (eating behaviors, food consumption, physical activity, beverage consumption) using generalized linear mixed models.

RESULTS

On average, students slept 1.5 hours (95% confidence interval 1.3-1.7) more and had a sleep midpoint 1.9 hours (1.8-2.1) later on weekend nights compared to school nights. Female students had larger increases in sleep duration on weekend nights than males but similar timing differences. Sleep duration differences were uncorrelated with sleep timing differences (r = 0.01). Neither duration nor timing differences were associated with overweight, obesity, or any of the eating behaviors we examined. However, sleeping longer on weekend nights than on school nights was associated with lower probability of being active 6-7 days per week (p = .02).

CONCLUSIONS

Adolescents have substantial sleep duration and sleep timing differences on weekend nights vs. school nights. While these differences may not be associated with weight status or weight-related behaviors, they reflect the reality that most adolescents have schedules that restrict their sleep.

Fruit and vegetables consumption among school-going adolescents: Findings from the baseline survey of an intervention program in a semi-urban area of Dhaka, Bangladesh

INTRODUCTION

Interventions aimed at promoting healthy eating habits in adolescence can help prevent chronic diseases and promote healthy ageing. The aim of this paper is to describe the fruit and vegetables consumption habits of adolescents in Dhaka, Bangladesh as well as to identify the socio-environmental, personal, and behavioral factors that influence these habits.

MATERIALS AND METHODS

The baseline data from an intervention study involving 823 grade ten students from two randomly selected secondary schools in a semi-urban area of Dhaka were analyzed. The intake of fruit and vegetables was measured in terms of serving size per day. Hierarchical multiple regression was used to assess the ability of socio-environmental factors such as social support, perceived barriers, and living with patient with chronic diseases; personal factors such as knowledge, self-rated practice, behavioral intention, and body mass index; and behavioral factors such as physical activity, sedentary hours, and sleep duration to predict the level of daily fruit and vegetables intake, after controlling the effect of demographic characteristics of adolescents.

RESULTS

The average daily consumption of fruit and vegetables was 1.22 and 1.99 servings, respectively. Only one-fifth of the respondents (21%) reported eating five servings of fruit and vegetables a day. Inaccessibility at home was reported as the most perceived barrier for both fruit and vegetables intake. Adolescents' higher fruit and vegetables intake was found to be associated with higher maternal educational attainment, more social support, adequate self-rated practice, positive behavioral intention, higher body mass index, better physical activity, and adequate daily sleeping.

CONCLUSION

The findings revealed insufficient fruit and vegetables intake among adolescents in a semi-urban area of Bangladesh and associated socio-environmental, personal, and behavioral factors that were utilized in developing an intervention program for this transient age group.

TRIAL REGISTRATION

Trial was registered at ClinicalTrials.gov (NCT03975335) https://clinicaltrials.gov/ct2/show/NCT03975335 on June 01, 2019.

Assessing Changes in Adolescents' Sleep Characteristics and Dietary Quality in the START Study, a Natural Experiment on Delayed School Start Time Policies

BACKGROUND

Sleep duration, quality, and timing may influence dietary quality. In adults, poor dietary quality is a risk factor for numerous chronic diseases. It is unclear how these various sleep domains influence adolescents' diets because prior population-based studies have not effectively manipulated sleep, did not include objective sleep measures, and had short follow-up times.

OBJECTIVES

The objectives of this study were to examine 1) how adolescent sleep characteristics relate to dietary quality; and 2) how delay in high school start times (which lengthened sleep duration) affects dietary quality over 2 y.

METHODS

In the START study, adolescents (grades 9-11, n = 423) attending 5 high schools in the Minneapolis, Minnesota metropolitan area were annually assessed in 3 waves (2016-2018). At Baseline, all schools started "early" (07:30 or 07:45). From Follow-up 1 through Follow-up 2, 2 "policy change schools" shifted to later start times (to 08:20 and 08:50). Three "comparison schools" maintained their early start throughout. Sleep characteristics were measured with actigraphy. Mixed-effect regression models were used to examine cross-sectional and longitudinal associations of sleep characteristics with dietary quality, and school start time policy change with dietary quality change.

RESULTS

Cross-sectionally, later sleep midpoint and onset were associated with dietary quality scores 1.6-1.7 lower (both P < 0.05). However, no prospective associations were observed between sleep characteristics and dietary quality in longitudinal models. Shifting to later school start time tended to be associated with a 2.4-point increase in dietary quality score (P = 0.09) at Follow-up 1, but was not associated with change in dietary quality scores at Follow-up 2 (P = 0.35).

CONCLUSIONS

High school students attending delayed-start schools maintained better dietary quality than students in comparison schools; however, differences were not statistically significant. Overall study findings highlight the complexity of the relation between sleep behavior and diet in adolescence.

Sleep Quality and Duration in European Adolescents (The AdolesHealth Study): A Cross-Sectional, Quantitative Study

Sleep is a vital element of adolescents' overall health; it influences their body and mind and thus affects their quality of life. Adequate sleep quality and duration are essential for maintaining optimal metabolic health and lowering the risk of developing several medical conditions, such as cardiovascular disease. The current study aimed to assess the perceived sleep quality and duration of 1717 European adolescents from three different European countries (Spain, Iceland and Estonia) aged 13- to 16-years (900 boys, 817 girls) using the Pittsburgh Sleep Quality Index (PSQI). A multivariate analysis of variance (MANOVA) was performed to examine differences between groups and two-factor analysis of variance (ANOVA) was used to analyze city and age differences. The probability of having poor sleep quality and duration was calculated by Odd-Ratio (OR). Our study found poor sleep quality in 44% of the boys and 53% of the girls, whereas 68% and 69%, respectively did not get the recommended hours of sleep (i.e., 8-10 h). No difference was found between adolescents from Estonia, Iceland and Spain regarding sleep duration. In contrast, Spanish and Estonian adolescents reported higher probabilities of having poor sleep quality. Finally, girls had a significantly higher probability of poor sleep quality than boys.

Do types of snacks, sleep hours, and eating places affect nutritional intakes and its adequacy in adolescents?

BACKGROUND/OBJECTIVES

High-quality meal intake, including snacks, is necessary for optimal development during adolescence. The purpose of this study was to evaluate the nutritional intake of adolescents and the quality of their diet according to snack type, eating location, and sleep hours.

SUBJECTS/METHODS

A survey of middle school students living in Seoul and Gyeonggi province was conducted using questionnaires and the 24-h recall method to collect data on the 1-day dietary intake of the students from March to May, 2018. The data were analyzed using SPSS 23.0 and the CAN program.

RESULTS

The average nutritional intake status among the respondents showed that the energy intake was lower than the recommended, showing 1,914.8 kcal for middle school boys and 1,752.7 kcal for girls. In terms of the nutritional intake status by gender, only the consumption of protein and niacin were significantly higher in boys than girls (P < 0.05). According to the sleep amounts, vitamin C intake was significantly higher in the sleep-deprived group than in the sleep-moderate or sleep-recommended group (P < 0.05), but the intake did not meet the recommendation in any group. The lower density nutrients found in the index of nutritional quality according to eating places were vitamin C, calcium, iron, and folic acid. School meals showed a higher nutritional density in protein, vitamin B₁, and niacin compared to convenience store meals (P < 0.05).

CONCLUSIONS

This study suggested that sleep amount, and eating place affected the dietary quality of adolescents.

Mediterranean Diet, Screen-Time-Based Sedentary Behavior and Their Interaction Effect on Adiposity in European Adolescents: The HELENA Study

Childhood obesity is a worldwide epidemic. Mediterranean diet (MD) is inversely associated with childhood obesity, but the interaction with other environmental factors, such screen time, might influence the health benefits of a high MD adherence in adolescents. The aim of the present study was to assess whether an association between MD and screen time exists in European adolescents. Moreover, we also explored whether sedentary time has a modulatory effect on the association between MD and adiposity. Adherence to the MD (24 h recalls), screen time (questionnaire), pubertal development, body mass index (BMI), fat mass index (FMI) and waist circumference (WC) were evaluated in 2053 adolescents (54.7% females), aged 12.5–17.5 years. In females, MD adherence was associated with lower BMI and FMI only when they were exposed to less than 338 min/day of screen time (81.8% of females); MD adherence was also associated with lower WC only when females were exposed to less than 143 min/day of screen time (31.5% of females). No significant MD-screen time interaction was observed in males. In conclusion, screen-time-based sedentary behaviours had a modulatory effect in the association between MD adherence and adiposity in European female adolescents.

A chrononutrition perspective of diet quality and eating behaviors of Brazilian adolescents in associated with sleep duration

It is well recognized that sleep and food intake exhibit 24-h patterns and disturbances of these patterns can lead to health problems. Cross-sectional and prospective studies suggest that diet quality and eating behaviors are negatively affected by short sleep duration. Adolescence is a particularly vulnerable period for the emergence of inadequate sleep and diet patterns. The aim of the study was to investigate associations, from a chrononutrition perspective, of diet quality, nutrients intake, and eating behaviors (eating frequency, eating period, and time-interval between eating occasions) in relation to sleep duration among a multi-ethnic cohort of Brazilian adolescents. Data were collected by the 2015 ISA-Capital survey, a population-based cross-sectional study comprising 419 adolescents of both sexes (12-19 years old) of São Paulo, Brazil. Demographic, socioeconomic, anthropometric, and lifestyle, including sleep duration, data were obtained from an interviewer-administered structured questionnaire. Dietary data were obtained by 24-h dietary recall (24-HDR), and diet quality was assessed by the Brazilian Healthy Eating Index - Revised (BHEI-R), validated for the Brazilian population. The independent associations between sleep duration categories (i.e., <8 h as short sleep and 8-10 h as adequate sleep), and dietary variables were assessed after adjustments for covariates. Multiple linear, logistic, and Poison regression models were used, depending on the variable. Diet quality, nutrients intake, and eating behaviors differed according to adolescents' sleep duration. Approximately 36% of adolescents were sleep deprived. They presented poorer diet quality (53 points, p = .034) and eating behaviors characterized by lower probability of having lunch (88%, p < .001) and dinner (71%, p < .001) and higher probabilities of eating breakfast (87%, p < .001) and morning snack (26%, p = .001). These adolescents compared to those with adequate sleep duration also had, from snacks and in the 24-h cycle, higher contribution of available carbohydrates (8%, p < .001; 50%, p = .024) and total sugar (6%, p < .001; 21%, p < .001) and added sugar (3%, p < .001; 15%, p < .001). The chrononutrition characteristics of sleep-deprived adolescents were marked by longer eating periods (12 h, p < .001) and time-interval between eating occasions (3 h, p < .001) than adolescents with adequate sleep duration. These differences point to the relevance of the interrelation between sleep and diet, i.e., disruption of circadian cycles and consequent metabolic health problems, to inform public health policies and clinical interventions.

Associations between paediatric fatigue and eating behaviours

BACKGROUND

In adults, poor sleep quality is associated with increased obesogenic eating behaviours; less is known about this relationship in youth. The objectives of this study were to assess the strength of association between fatigue-related quality of life (QoL) and eating behaviours among youth and to describe the associations in participants with percent body fat (%BF) above and below the 90th percentile for sex and age.

METHODS

Caregiver-reported measures of fatigue (Pediatric QoL Multidimensional Fatigue Scale) and eating behaviours (Child Eating Behaviour Questionnaire) were obtained from participants aged 8-17 years. %BF was measured by iDXA and grouped by sex- and age-specific percentiles. Multiple linear regression adjusting for age, sex and race/ethnicity was used.

RESULTS

Of the 352 participants (49% male), 44.6% had %BF >90th percentile. General, sleep/rest and cognitive fatigue QoL was inversely associated with food approach behaviours: food responsiveness, enjoyment of food, emotional overeating and desire to drink. For participants with %BF >90th percentile, higher general fatigue QoL was associated with higher satiety responsiveness (0.13; 95% confidence interval [CI 0.03, 0.24]). For participants with %BF ≤90th percentile, higher general fatigue QoL was associated with less satiety responsiveness (-0.16; 95% CI [-0.31, -0.01]).

CONCLUSION

Less fatigue symptoms were associated with less behaviours associated with food approach among paediatric participants. For participants with %BF >90th percentile, less symptoms of general fatigues corresponded with more satiety. Though causation has yet to be established, youth with elevated %BF should be screened for fatigue symptoms and offered counselling on sleep hygiene or a sleep medicine referral to help mitigate weight gain.

Low energy intake and dietary quality are associated with low objective sleep quality in young Japanese women

Literature reports suggest that subjective sleep quality is associated with nutrient intake in elderly people and workers. However, few studies have suggested an association between objective sleep quality and dietary intake in adolescents and young women. We hypothesized that objective sleep quality is associated with dietary intake in adolescents and young women. We evaluated the association between energy and nutrient intake and objective sleep quality in adolescents and young Japanese women. In a cross-sectional study of 80 women aged 18-27 years, dietary intake was assessed using the self-administered diet history questionnaire. Objective sleep quality was assessed by actigraphy. Lifestyle characteristics, dietary habits, and mental health were assessed using specific questionnaires. Subjects were classified into 3 groups according to sleep efficiency (SE <80%, 80%-85%, and ≥85%), and the relationships between dietary intake and objective sleep quality were statistically evaluated. No significant differences occurred in lifestyle characteristics, physical activity levels, eating behavior, and mental health status among the 3 SE groups. Energy intake was significantly lower in the low-SE group than in the middle- (P = .004) and high- (P = .015) SE groups. Protein intake was significantly lower in the low-SE group than in the high-SE group (P = .034). The mean energy-adjusted intakes of vitamin K, vitamin B₂, potassium, magnesium, iron, zinc, copper, and tryptophan were significantly lower in the low-SE group than in the high-SE group. Adequate energy intake and a high-quality diet including vitamins, minerals, and tryptophan may result in high sleep quality and help prevent sleep problems.

Weight Status, Adherence to the Mediterranean Diet, Physical Activity Level, and Sleep Behavior of Italian Junior High School Adolescents

Inadequate diet, physical activity, and sleep-related behaviors are potential risk factors for overweight and obese, therefore we investigated the relations between body mass index (BMI) and behavioral factors in a sample of Italian adolescents. Four hundred nine Italian secondary school students (46% females, 12.5 ± 0.6 y.o.) were enrolled in this cross-sectional study. Anthropometric measures, adherence to the Mediterranean Diet (KIDMED), physical activity level (PAQ-C), sleep duration, daytime sleepiness (PDSS), sleep quality, and school achievement data were collected through an online questionnaire. The percentage of overweight adolescents was slightly lower (14%) compared to the regional and the national figures. Approximately 88% of the sample reported a medium/high adherence to the Mediterranean Diet and 77% a moderate/vigorous physical activity level. The average sleep duration was in line with the international sleep recommendation for adolescents and 82% had a medium/high sleep quality. No differences were found between genders except for BMI (lower in females). Unexpectedly, no differences were found among the BMI groups (normal weight vs. overweight vs. obese) for lifestyle variables; in contrast, Mediterranean Diet adherence was associated with sleep habits. Further investigation is required to better explore the associations among behavioral variables involved in adolescents' healthy development.

Sleep duration and eating behaviours in youth: a scoping review protocol

INTRODUCTION

Developmental alterations to the circadian rhythm, in combination with lifestyle changes (eg, changes in school start time, part-time employment), contribute to insufficient sleep among youth. Insufficient sleep is associated with poor eating behaviours in other developmental stages (ie, childhood, adulthood); however, it is currently unknown if this finding generalises to youth. Consequently, identifying the characteristics and results of the studies examining this relationship in youth populations is necessary to guide the future direction of research in this field.

METHODS AND ANALYSIS

We will conduct a scoping review to investigate the literature examining the relationship between sleep duration and eating behaviours in youth. The proposed scoping review will follow the standard six-stage protocol outlined by Arksey and O'Malley. To acquire relevant publications, systematic searches were conducted in PubMed, CINHAL, PsycINFO and Scopus in August 2019. Following this, a scan of the grey literature will be conducted. All relevant publications will be screened for their eligibility based on the predefined inclusion and exclusion criteria. A data extraction tool will be used to collate, summarise and report the results. The findings of the scoping review will be reviewed by relevant stakeholders to aid in interpreting and disseminating the findings. The proposed review will identify existing gaps in the literature and inform the conduct of future studies aimed at understanding the effects of insufficient/excessive sleep and the eating behaviours of youth.

ETHICS AND DISSEMINATION

This scoping review does not require ethics approval. Following the completion of the study, the findings will be disseminated at scientific meetings, submitted for peer-reviewed publication and translated to an accessible format for other relevant stakeholders.

Actigraphic Sleep and Dietary Macronutrient Intake in Children Aged 6-9 Years Old: A Pilot Study

The objective of this study was to examine the relationship between different sleep parameters and energy and macronutrient intake in school-aged children. A total of 203 children 6 to 9 years of age participated in this cross-sectional study. Anthropometric measurements were taken first. Diet was assessed with 3-day food logs and sleep was measured with a questionnaire on sleep quality and a wrist actigraph worn for at least 7 days. A decrease of 165.45 kcal was observed per each additional hour of sleep during the week (β (95% CI) = −165.45 (−274.01, −56.88); p = 0.003). This relationship was also observed for fat (β (95% CI) = −11.14 (−18.44, −3.84); p = 0.003) and protein (β (95% CI) = −13.27 (−22.52, −4.02); p = 0.005). An increase in weekend sleep efficiencies for those under the recommended threshold of 85% also had a similar association with energy (β (95% CI) = −847.43 (−1566.77, 128.09); p = 0.021) and carbohydrate (β (95% CI) = −83.96 (−161.76, −6.15); p = 0.035)) intake. An increase in habitual sleep variability was related with a slight increase in protein intake (β (95% CI) = 0.32 (0.031, 0.62); p = 0.031). Children who slept less had a higher energy intake, especially from fat and protein and those who presented inefficient sleep had a higher carbohydrate intake. Strategies to enhance sleep quality and quantity combined with dietary recommendations could help to improve energy and macronutrient intake levels in children.

Poor sleep and adolescent obesity risk: a narrative review of potential mechanisms

Poor sleep is related to increased obesity risk in adolescents, though the mechanisms of this relationship are unclear. This paper presents a conceptual framework of the various pathways that have been proposed to drive this relationship. In this framework, increased food reward, emotional reactivity, decreased inhibitory control, metabolic disturbances, poorer dietary quality, and disrupted meal timings may increase the likelihood of increasing overall energy intake. This paper further notes how poor sleep increases sedentary behavior and screen time, which likely limits overall energy expenditure. The model posits that these mechanisms result in an imbalance of energy intake and expenditure following poor sleep, intensifying the overall risk for obesity. Increases in food reward processes, decreases in insulin sensitivity, disrupted meal timing, and increases in sedentary behavior seem to be the most compelling mechanisms linking poor sleep with increased obesity risk in adolescents. Future directions and clinical implications of this framework are discussed.

Diet quality, consumption of seafood and eggs are associated with sleep quality among Chinese urban adults: A cross-sectional study in eight cities of China

Growing evidence has suggested that dietary modification is implicated with sleep alteration. Our study aimed to determine whether an association between diet in terms of diet quality, certain food consumption, and dietary nutrients intake and sleep quality existed in Chinese urban adults, which has been fully investigated. A cross-sectional study was conducted among urban adults from eight Chinese cities. Total of 1,548 participants remained in the final analysis. Sleep quality was evaluated by the Chinese version of the Pittsburg Sleep Questionnaire Index. Diet quality, evaluated by Chinese Healthy Diet Index, and dietary intake, including food groups and nutrients, were derived from a semiquantitative Food Intake Frequencies Questionnaire and a single 24-hr dietary recall. The relationship between dietary variables and sleep quality was examined using multivariable logistic regression models. Logistic regression analysis indicated that better diet quality, which features greater food diversity, higher ingestion of fruits and fish, along with higher seafood consumption, lower eggs consumption, and higher total energy intake, was significantly associated with lower risk of poor sleep quality in the crude model and the fully adjusted model with adjustment for gender, age, self-rated health condition, self-assessed mental stress, smoking, hypertension, and BMI. Therefore, we reached a conclusion that diet quality and certain food consumption were related to sleep quality. Although the associations observed in the cross-sectional study require further investigation in prospective studies, dietary intervention, such as enhancement in food diversity and consumption of fruits and seafood, might serve as a probable strategy for sleep improvement.

Short sleep duration is related to kidney-related biomarkers, but not lipid profile and diet quality in diabetic nephropathy patients

Objectives: Diabetic nephropathy may adversely influence on sleep duration. The quality of diet may also be affected by both sleep duration and diabetes nephropathy. Therefore, lower diet quality in short sleepers-diabetic nephropathy patients might be related to higher metabolic abnormalities. In the present study, we investigated if sleep duration is related to diet quality indices and biochemical markers in diabetic nephropathy patients. Method: This cross-sectional study was conducted among 237 diabetic nephropathy patients, randomly selected from patients attending in the Alzahra University Hospital, Isfahan, Iran. Usual dietary intake was assessed using validated food frequency questionnaire. Diet quality indices (including diet diversity score, dietary energy density, mean adequacy ratio, and nutrient adequacy ratio) were calculated based on standard definitions. Sleep duration was estimated using self-reported nocturnal hours of sleep. Results: Short sleepers (5-6 h) had higher blood urea nitrogen and creatinine compared with those who slept more than 7.5 h (20.26 + 0.23 mg/dl vs. 17.61 + 0.30 mg/dl, P < 0.0001, and 1.98 + 0.27 mg/dl vs. 1.90 + 0.24 mg/dl, P = 0.03, respectively). Serum triglyceride levels were positively correlated with sleep duration (P = 0.02). Diet quality indices were not significantly associated with sleep duration. Conclusion: Higher sleep duration is significantly related to lower kidney-related biomarkers in diabetic nephropathy patients. Diet quality indices were not associated with sleep duration in diabetic nephropathy patients. More longitudinal studies are required to evaluate the associations of sleep duration, diet quality and biochemical markers in diabetic nephropathy patients.

Improved Diet Quality and Nutrient Adequacy in Children and Adolescents with Abdominal Obesity after a Lifestyle Intervention

High rates of childhood obesity require integral treatment with lifestyle modifications that achieve weight loss. We evaluated a lifestyle intervention on nutrient adequacy and diet quality in children and adolescents with abdominal obesity. A randomized controlled trial was performed on 107 participants, assigned either to a usual care group or to an intensive care group that followed a moderate hypocaloric Mediterranean diet and received nutritional education. Intake adequacy was evaluated using Dietary Reference Intakes and diet quality through the Diet Quality Index for Adolescents (DQI-A), the Healthy Lifestyle Diet-Index (HLD-I) and the Mediterranean Diet Quality Index (KIDMED). Both groups achieved a significant reduction in BMI standard deviation score (BMI-SDS), glucose and total cholesterol levels. Intake of Calcium, Iodine and vitamin D were higher in the intensive care group, with enhanced compliance with recommendations. Higher dietary scores were associated with lower micronutrient inadequacy. DQI-A and HLD-I were significantly higher in the intensive care group vs. usual care group after the treatment. In conclusion, we observed that an intensive lifestyle intervention was able to reduce BMI-SDS in children with abdominal obesity. Furthermore, participants significantly improved dietary indices getting closer to the nutritional recommendations. Therefore, these diet quality indices could be a valid indicator to evaluate micronutrient adequacy.

Sleep indices and eating behaviours in young adults: findings from Project EAT

OBJECTIVE

To test the associations between sleep indices and eating behaviours in young adults, a group vulnerable to suboptimal sleep.

DESIGN

Cross-sectional analysis of survey measures of sleep (i.e. time in bed, variability, timing and quality) and dietary patterns (i.e. breakfast skipping, eating at fast-food restaurants, consumption of sports and energy drinks, and sugar-free, sugar-sweetened and caffeinated beverages).

SETTING

Minneapolis/St. Paul metropolitan area of Minnesota (USA).

SUBJECTS

A total of 1854 respondents (20-30 years, 55·6 % female) from the 2008-2009 survey conducted for the third wave of the population-based Project EAT (Eating and Activity in Teens and Young Adults) study.

RESULTS

After adjustment for demographic and behavioural covariates in linear regression models, those who went to bed after 00.30 hours consumed 0·3 more servings of sugar-sweetened beverages per day, consumed 1·7 times more energy drinks, skipped breakfast 1·8 more times per week and consumed fast food 0·3 more times per week compared with those who went to bed before 22.30 hours. Reported sleep quality in the lowest (Q1) v. highest (Q3) tertile was associated with more intake of energy drinks (Q3 v. Q1, prevalence ratio, 95 % CI: 1·79, 1·24, 2·34), sports drinks (1·28, 1·00, 1·55) and breakfast skipping (adjusted mean, 95 % CI: Q1: 4·03, 3·81, 4·26; Q3: 3·43, 3·17, 3·69). Time in bed and sleep variability were associated with few eating behaviours.

CONCLUSIONS

Some, but not all, sleep indices were related to problematic eating behaviours. Sleep habits may be important to address in interventions and policies that target improvements in eating patterns and health outcomes.

Sleep and Dietary Patterns in Pregnancy: Findings from the GUSTO Cohort

Evidence on the association between sleep, diet, and eating behaviors in pregnant women is lacking. We examine this in a cohort of apparently healthy pregnant women. At 26-28 weeks gestation, 497 participants completed the Pittsburgh Sleep Quality Index to assess sleep and a 24-h recall to assess dietary intake. Diet quality was assessed by the Healthy Eating Index for pregnant women in Singapore (HEI-SGP) score and previously derived dietary patterns (vegetables-fruit-rice, seafood-noodles, and pasta-cheese-meat pattern). Eating behaviors studied included the longest night-time fasting interval, frequency of consumption occasions, energy from discretionary foods, and nighttime eating. Adjusted means were estimated between poor/good quality and short/normal sleepers using linear regressions, including covariates. Good sleep quality versus poor sleep quality, was associated with better diet quality (mean HEI-SGP 54.6 vs. 52.0; p = 0.032), greater adherence to the vegetables-fruit-rice pattern (mean 0.03 vs. -0.15; p = 0.039), lesser adherence to the seafood-noodle pattern (mean -0.14 vs. 0.03; p = 0.024), and a trending lower calories from discretionary foods (mean 330.5 vs. 382.6 kcal; p = 0.073), after adjusting for covariates. After additional adjustment for anxiety, only sleep quality and the seafood-noodle pattern remained significantly associated (p = 0.018). Short sleep was not associated with any diet or eating behavior. In conclusion, good sleep quality is associated with a better diet quality and a greater adherence to the vegetable-fruit-rice pattern, but with lesser adherence to the seafood-noodle diets in pregnant women.

Relationship between sleep duration and childhood obesity: Systematic review including the potential underlying mechanisms

AIM

The prevalence of obesity is continually increasing worldwide. Determining risk factors for obesity may facilitate effective preventive programs. The present review focuses on sleep duration as a potential risk factor for childhood obesity. The aim is to summarize the evidence on the association of sleep duration and obesity and to discuss the underlying potential physiological and/or pathophysiological mechanisms.

DATA SYNTHESIS

The Ovid MEDLINE, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for papers using text words with appropriate truncation and relevant indexing terms. All studies objectively measuring sleep duration and investigating the association between sleep duration and obesity or factors (lifestyle and hormonal) possibly associated with obesity were included, without making restrictions based on study design or language. Data from eligible studies were extracted in tabular form and summarized narratively. After removing duplicates, 3540 articles were obtained. Finally, 33 studies (including 3 randomized controlled trials and 30 observational studies) were included in the review.

CONCLUSION

Sleep duration seems to influence weight gain in children, however, the underlying explanatory mechanisms are still uncertain. In our review only the link between short sleep duration and the development of insulin resistance, sedentarism and unhealthy dietary patterns could be verified, while the role of other mediators, such as physical activity, screen time, change in ghrelin and leptin levels, remained uncertain. There are numerous evidence gaps. To answer the remaining questions, there is a need for studies meeting high methodological standards and including a large number of children.

Exploring the mediating role of energy balance-related behaviours in the association between sleep duration and obesity in European adults. The SPOTLIGHT project

Sleep restriction is a risk factor for weight gain and obesity. Few studies have formally investigated the mediating role of energy balance-related behaviours in the sleep - obesity association. The aim of this study was to explore the mediating role of physical activity, sedentary behaviours and dietary habits in the association of sleep duration with obesity in adults in five European urban regions. Data on self-reported sleep duration, energy balance-related behaviours, height and weight and other covariates were collected between February and September 2014 from participants to the SPOTLIGHT survey (N=5900, mean age 52years). Participants were recruited from 60 urban neighbourhoods in Belgium, France, Hungary, the Netherlands and the United Kingdom. Multilevel logistic regression analyses were used to assess the associations of sleep duration, energy balance-related behaviours and obesity and mediating effects were calculated using MacKinnon's product-of-coefficients method. Results indicated that a 1h increase in sleeping time was associated with a 14% lower likelihood of being obese (OR=0.86, 95%CI=0.80; 0.93). Only work-related sedentary behaviour was identified as a statistically significant mediator in the association between sleep duration and obesity for the total sample, and youngest and oldest age group. We did not find evidence for a mediating role of dietary habits and physical activities.

Prevalence of adiposity and its association with sleep duration, quality, and timing among 9-12-year-old children in Guangzhou, China

BACKGROUND

Short sleep duration has been reported to be associated with obesity in children, but findings are not consistent. Since few studies have examined the relationship between more complex sleep characteristics and obesity, we examined the association between adiposity and self-reported sleep duration, bedtime, and sleep quality in 9-12-year-old Chinese children using multilevel mixed models.

METHODS

5518 children aged 9-12 years were recruited from 29 randomly selected primary schools in Guangzhou, China in 2014. Standardized questionnaires were used to obtain data to estimate sleep duration on typical weekdays and weekends. Sleep quality data were collected using the Children's Sleep Habits Questionnaire (CSHQ). Trained researchers undertook measurements of weight, height, and waist circumference (WC) for all participating children. Body mass index (BMI) z-scores were derived using the World Health Organization (WHO) child growth reference, and children were classified as overweight or obese using +1 and +2 SD as cut-offs, respectively. Percentage body fat (BF%) was calculated using bioelectrical impedance.

RESULTS

Longer sleep duration was inversely associated with BMI z-score (β = -0.16, p < 0.05), WC (β = -1.11, p < 0.05) and later bedtime was associated with higher BMI z-score (β = 0.03, p < 0.05), WC (β = 1.72, p < 0.001), and BF% (β = 0.15, p < 0.05) in multivariable multilevel mixed models, after adjustment for age, gender, physical activity, parental education level, and average monthly income. No association was seen between sleep quality and adiposity.

CONCLUSION

Shorter sleep duration and later bedtime are associated with higher adiposity indices in early adolescents from southern China.

Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth

The objective of this systematic review was to examine the relationships between objectively and subjectively measured sleep duration and various health indicators in children and youth aged 5-17 years. Online databases were searched in January 2015 with no date or study design limits. Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth aged 5-17 years), intervention/exposure/comparator (various sleep durations), and outcome (adiposity, emotional regulation, cognition/academic achievement, quality of life/well-being, harms/injuries, and cardiometabolic biomarkers) criteria. Because of high levels of heterogeneity across studies, narrative syntheses were employed. A total of 141 articles (110 unique samples), including 592 215 unique participants from 40 different countries, met inclusion criteria. Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being. The evidence was mixed and/or limited for the association between sleep duration and cognition, harms/injuries, and cardiometabolic biomarkers. The quality of evidence ranged from very low to high across study designs and health indicators. In conclusion, we confirmed previous investigations showing that shorter sleep duration is associated with adverse physical and mental health outcomes. However, the available evidence relies heavily on cross-sectional studies using self-reported sleep. To better inform contemporary sleep recommendations, there is a need for sleep restriction/extension interventions that examine the changes in different outcome measures against various amounts of objectively measured sleep to have a better sense of dose-response relationships.

Lack of sleep as a contributor to obesity in adolescents: impacts on eating and activity behaviors

Background

Sleep is an important contributor to physical and mental health; however, chronic sleep deprivation has become common in adolescents, especially on weekdays. Adolescents aged 14–17 years are recommended to sleep between 8 and 10 h per night to maximize overall health and well-being. Although sleep needs may vary between individuals, sleep duration recommendations are important for surveillance and help inform policies, interventions, and the population of healthy sleep behaviors. Long sleepers are very rare among teenagers and sleeping too much is not a problem per se; only insufficient sleep is associated with adverse health outcomes in the pediatric population. Causes of insufficient sleep are numerous and chronic sleep deprivation poses a serious threat to the academic success, health and safety of adolescents. This article focuses on the link between insufficient sleep and obesity in adolescents.

Discussion

This “call to action” article argues that sleep should be taken more seriously by the public health community and by our society in general, i.e., given as much attention and resources as nutrition and physical activity. Not only that having a good night’s sleep is as important as eating a healthy diet and being regularly physically active for overall health, but sleeping habits also impact eating and screen time behaviors and, therefore, can influence body weight control.

Summary

Short sleep duration, poor sleep quality, and late bedtimes are all associated with excess food intake, poor diet quality, and obesity in adolescents. Sleep, sedentary behavior, physical activity and diet all interact and influence each other to ultimately impact health. A holistic approach to health (i.e., the whole day matters) targeting all of these behaviors synergistically is needed to optimize the impact of our interventions. Sleep is not a waste of time and sleep hygiene is an important factor to consider in the prevention and treatment of obesity.

Associations of sleep duration and quality with disinhibited eating behaviors in adolescent girls at-risk for type 2 diabetes

OBJECTIVES

Short sleep duration and daytime sleepiness have been associated with an increased risk for the onset of type 2 diabetes in adults. There has been far less attention to the characterization of sleep in adolescents at-risk for diabetes or to the possible behavioral mechanisms, such as disinhibited eating, through which sleep may affect metabolic functioning.

METHODS

We evaluated the associations of sleep duration and daytime sleepiness with a multi-modal assessment of disinhibited eating in 119 adolescent girls at-risk for type 2 diabetes based upon being overweight/obese and having a family history of diabetes. Girls also endorsed mild-to-moderate depressive symptoms. Adolescents reported sleep duration and daytime sleepiness with the Sleep Habits Survey and Children's Sleep Habits Questionnaire. They were administered a series of successive test meals to measure total energy intake and eating in the absence of hunger (EAH). Adolescent binge eating was assessed with the Eating Disorder Examination interview.

RESULTS

Accounting for age, race, puberty, body composition, depressive symptoms, and perceived stress, reported sleep duration was positively related to test meal total energy intake (p=0.04), but not to EAH. Adjusting for the same covariates, daytime sleepiness was associated with a greater odds of objective binge eating in the previous month (p=0.009).

CONCLUSIONS

In adolescent girls at-risk for type 2 diabetes, reported sleep characteristics are associated with disinhibited eating behaviors that have been linked to excessive weight and adverse metabolic outcomes. Future studies are called for to evaluate these links using objective measures of sleep.

Macronutrient Intakes in Infancy Are Associated with Sleep Duration in Toddlerhood

BACKGROUND

Dietary composition has been associated with sleep indexes. However, most of the evidence is based on cross-sectional data, and studies in young children are lacking.

OBJECTIVE

The aim of this study was to explore the longitudinal associations of macronutrient composition of the diet with sleep duration and consolidation (number of awakenings) in infancy and early childhood.

METHODS

The study was performed in 3465 children from the Generation R Study, a population-based cohort study in the Netherlands. Mothers reported their child's food intake at 13 mo of age by using a validated food-frequency questionnaire and their child's sleep patterns at 2 and 3 y of age. We used nutrient substitution models to assess the associations of relative macronutrient intakes with sleep indexes and adjusted the models for sociodemographic and lifestyle factors.

RESULTS

Isocaloric substitution of fat intake by protein or carbohydrate in infancy was associated with longer total sleep duration at 2 but not 3 y of age. For each 5% increase in energy intake of either protein or carbohydrate at the expense of fat, sleep duration at 2 y of age was longer by 6 min (95% CI: 0.4, 12 min) and 4 min (95% CI: 2, 6 min), respectively. Further exploration of macronutrient subtypes indicated no consistent differences between saturated or unsaturated fat and that intake of plant compared with animal protein or Trp did not explain the association of higher total protein intake with longer sleep duration at 2 y of age. Replacing unsaturated with saturated fat was associated with 7 min (95% CI: -13, -1 min) shorter total sleep duration at 3 y of age. Macronutrient intakes were not associated with sleep consolidation.

CONCLUSIONS

Our results suggest that the macronutrient composition of the diet is associated with sleep duration in young children. Future research should further study the causality of this association and explore the underlying mechanisms.

Short Sleep Duration Is Related to Emerging Cardiovascular Risk Factors in Obese Children

OBJECTIVE

The aim of the present study was to evaluate the influence of sleep duration on cardiovascular risk factors in obese children.

METHODS

Cross-sectional analysis of 90 obese children ages 7 to 16 years. Anthropometric and clinical evaluation with specification of dietary and lifestyle habits was carried out during an office visit. Sleep duration was evaluated by the BEARS (B = bedtime issues, E = excessive daytime sleepiness, A = night awakening, R = regularity and duration of sleep, S = snoring) questionnaire on children's sleep characteristics. Sleep time adequacy by age was assessed according to the criteria of the National Sleep Foundation. Biochemical blood variables indicative of metabolic risk (glucose, lipid profile, and insulin) were obtained. Emergent new factors of metabolic risk, including high-sensitive C-reactive protein, γ-glutamyltranspeptidase, homocysteine, retinol-binding protein 4 (RBP4), thyroid-stimulating hormone (TSH), inflammatory markers, and the adipokines leptin, adiponectin, and ghrelin were also evaluated. The relations between the duration of sleep and these variables were analyzed by general lineal model analysis. Significant variables were introduced in logistic regression analysis to determine the odds ratio (OR) and 95% confidence interval (CI) of cardiometabolic factors with respect to sleep.

RESULTS

Children who slept for short duration were significantly more at risk of severe central obesity. In the regression model, the mean arterial pressure (odds ratio [OR] 1.10, 95% confidence interval [CI] 1.02-1.17, P = 0.008), homocysteine (OR 1.41, 95% CI 1.08-1.84, P = 0.013), RBP4 (OR 1.78, 95% CI 1.15-2.78, P = 0.010), and TSH (OR 2.01, 95% CI 1.21-3.34, P = 0.007) remain as significant independent predictors related to short sleep duration. We did not find any association between sleep duration and inflammatory markers or adipokines.

CONCLUSIONS

Short sleep duration increases the severity of obesity and is related to cardiovascular risk factors in children.

Bone Characteristics and Their Determinants in Adolescents and Young Adults with Early-Onset Severe Obesity

Childhood obesity is associated with compromised bone health. We studied bone characteristics and their determinants in obese young adults. The study included 68 subjects with early-onset severe obesity and 73 normal-weight controls. Data on physical activity (PA), diet and smoking were collected. Bone characteristics were measured using peripheral QCT. The obese and control subjects were similar in age (mean 19.6 ± 2.6 years) and height but BMIs differed (39.7 and 22.6 kg/m(2)). A clustering of unhealthy lifestyles was marked: Obese subjects reported less supervised PA in childhood, adolescence and currently (p < 0.03) and were more likely to smoke (p = 0.005), and had a lower healthy eating index (HEI) (p = 0.007) but similar alcohol consumption compared with controls. In obese women, all crude bone characteristics were higher than in controls; in men, the differences were smaller. Associations of lifestyle factors with bone characteristics were tested using partial correlations. Independently of BMI, supervised PA in adolescence and alcohol consumption were related positively to bone characteristics in both groups. HEI associated positively with bone characteristics only in controls, while smoking was a positive determinant of bone characteristics only in obese subjects. The multivariate model showed that the contribution of lifestyle factors to bone characteristics was minimal compared with BMI. Early-onset obesity is accompanied by poor dietary quality, sedentary lifestyle, and more frequent smoking, but the overall contribution of these lifestyle factors to bone strength is limited. Bone strength is more likely to be compromised in men and in unloaded bone sites in subjects with early-onset severe obesity. The impact of obesity-related endocrine changes on bone characteristics need to be evaluated in future studies.

Insufficient sleep among elementary and middle school students is linked with elevated soda consumption and other unhealthy dietary behaviors

OBJECTIVE

This study examines the extent to which insufficient sleep is associated with diet quality in students taking part in the Massachusetts Childhood Obesity Research Demonstration Project.

METHODS

Data were collected in Fall 2012 for all 4th and 7th grade children enrolled in public schools in two Massachusetts communities. During annual body mass index (BMI) screening, students completed a survey that assessed diet, physical activity, screen time, and sleep. Of the 2456 enrolled students, 1870 (76%) had complete survey data. Generalized estimating equations were used to examine associations between sleep duration and dietary outcomes (vegetables, fruits, 100% juice, juice drinks, soda, sugar-sweetened beverages and water), accounting for clustering by school. Models were adjusted for community, grade, race/ethnicity, gender, television in the bedroom, screen time, and physical activity.

RESULTS

In adjusted models, students who reported sleeping < 10 hours/day consumed soda more frequently (β = 0.11, 95% CI: 0.03, 0.20) and vegetables less frequently (β = -0.09, 95% CI: -0.18, -0.01) compared with students who reported ≥ 10 hours/day. No significant associations were observed between sleep duration and fruits, 100% juice, juice drinks or water.

CONCLUSIONS

In this population, insufficient sleep duration was associated with more frequent soda and less frequent vegetable consumption. Longitudinal research is needed to further examine these relationships.

Are sleep duration and sleep quality associated with diet quality, physical activity, and body weight status? A population-based study of Canadian children

OBJECTIVES

To describe sleep duration and sleep characteristics, and to examine the associations between sleep duration and characteristics and body weight status, diet quality, and physical activity levels among grade 5 children in Nova Scotia.

METHODS

A provincially representative sample of 5,560 grade 5 children and their parents in Nova Scotia was surveyed. Parents were asked to report their child's bedtime and wake-up time, and to indicate how often their child snored or felt sleepy during the day. Dietary intake and physical activity were selfreported by children using the Harvard Youth/Adolescent Food Frequency Questionnaire and the Physical Activity Questionnaire for Children respectively. Body weight status was determined using measured heights and weights. Linear and logistic random effects models with children nested within schools were used to test for associations.

RESULTS

Approximately half of the surveyed parents reported that their children were not getting adequate sleep at night. Longer sleep duration was statistically significantly associated with decreased risk for overweight and obesity independent of other sleep characteristics (OR = 0.82, 95% CI: 0.73, 0.91). Longer sleep duration was also associated with better diet quality and higher levels of physical activity.

CONCLUSIONS

These findings indicate a need for health promotion strategies to encourage adequate sleep and to promote healthy sleep environments among children. Given the links among sleep, body weight status and lifestyle behaviours, these messages should be included in public health interventions aimed at preventing obesity and promoting health among children.

Sleep patterns and obesity in childhood

PURPOSE OF REVIEW

To highlight the recent findings on sleep-obesity associations in children. We focus on sleep duration, sleep timing and chronotype, and describe the potential mechanisms underlying sleep-obesity associations.

RECENT FINDINGS

Poor sleep is increasingly common in children and associations between short sleep duration in early childhood and obesity are consistently found. Less is known about the infancy period, and the findings in adolescents are inconsistent. Sleep timing patterns may also contribute to obesity risk. Variable and shifted sleep schedules and evening chronotypes have recently been linked to adiposity in adults; less is known about children. Further, there is little understanding regarding the mechanisms of association. The timing of eating, dietary intake, obesogenic eating behaviors, and changes in appetite-regulating hormones have been identified as possible mechanisms for sleep-obesity associations and may be promising avenues for future research. Longitudinal and experimental work with children is needed to determine the nature of associations.

SUMMARY

Beyond sleep duration, sleep timing patterns may contribute to obesity risk. Biological and behavioral processes have been proposed as mechanisms that may explain the association. Understanding the pathways through which poor sleep patterns could increase obesity risk in children may provide novel avenues for intervention.

The impact of sleep and circadian disturbance on hormones and metabolism

The levels of several hormones fluctuate according to the light and dark cycle and are also affected by sleep, feeding, and general behavior. The regulation and metabolism of several hormones are influenced by interactions between the effects of sleep and the intrinsic circadian system; growth hormone, melatonin, cortisol, leptin, and ghrelin levels are highly correlated with sleep and circadian rhythmicity. There are also endogenous circadian mechanisms that serve to regulate glucose metabolism and similar rhythms pertaining to lipid metabolism, regulated through the actions of various clock genes. Sleep disturbance, which negatively impacts hormonal rhythms and metabolism, is also associated with obesity, insulin insensitivity, diabetes, hormonal imbalance, and appetite dysregulation. Circadian disruption, typically induced by shift work, may negatively impact health due to impaired glucose and lipid homeostasis, reversed melatonin and cortisol rhythms, and loss of clock gene rhythmicity.