Health behaviors, waist circumference and waist-to-height ratio in children

Influence of sugar consumption from foods with different degrees of processing on anthropometric indicators of children and adolescents after 18 months of follow-up

Excessive consumption of ultra-processed foods is associated with the development of metabolic changes in children and adolescents. However, the consumption of total sugars, monosaccharides and disaccharides present in these ultra-processed foods and other food groups and its association with anthropometric indicators must be evaluated. Therefore, this study aimed at analysing the influence of sugar consumption from foods with different degrees of processing on anthropometric indicators of children and adolescents after 18 months of follow-up. This cohort study was conducted among 492 children and adolescents aged 7-15 years. Information on food consumption and anthropometry was collected during three follow-up stages. NOVA classification was used for food categorisation. The influence of sugar consumption on the variation of anthropometric measurements over time was evaluated using generalised estimation equation models. During the analysis period, for each increase of 1 g/d in the consumption of total sugars and monosaccharides from ultra-processed foods, there was an increase of 0·002 kg/m² (P = 0·030) and 0·001 kg/m² (P = 0·019) in BMI/Age; increase of 0·073 (P < 0·001), 0·032 (P < 0·001) and 0·100 (P < 0·001) in the BMI/Age z-score; and increase of 0·001 cm (P = 0·001), 0·001 cm (P = 0·003) and 0·003 cm (P < 0·001) in waist circumference, with the consumption of total sugars, monosaccharides and disaccharides, respectively. Our study findings support the evidence that the consumption of total sugars, monosaccharides and disaccharides from ultra-processed foods is associated with weight gain and abdominal fat in children and adolescents, which may represent an important risk factor for excess weight in this age group.

Individual and family characteristics associated with health indicators at entry into multidisciplinary pediatric weight management: findings from the CANadian Pediatric Weight management Registry (CANPWR)

OBJECTIVES

(1) To explore individual and family characteristics related to anthropometric and cardiometabolic health indicators and (2) examine whether characteristics that correlate with cardiometabolic health indicators differ across severity of obesity at time of entry to Canadian pediatric weight management clinics.

METHODS

We conducted a cross-sectional analysis of 2-17 year olds with overweight or obesity who registered in the CANadian Pediatric Weight Management Registry (CANPWR) between May 2013 and October 2017 prior to their first clinic visit. Individual modifiable health behaviors included dietary intake, physical activity, screen time, and sleep. Family characteristics included parental BMI, family medical history, socioeconomic status and family structure. Linear mixed effects stepwise regression analysis was performed to determine which characteristics were related to each health indicator: BMI z-score; waist circumference; waist to height ratio; blood pressure; glycemia; HDL cholesterol; non-HDL cholesterol; triglycerides.

RESULTS

This study included 1296 children (mean age ± standard deviation: 12.1 ± 3.5 years; BMI z-score: 3.55 ± 1.29; 95.3% with obesity). Hours spent sleeping (estimated β = -0.10; 95% CI [-0.15, -0.05], p = 0.0001), hours per week of organized physical activity (estimated β = -0.32; 95% CI [-0.53, -0.11], p = 0.0026), daily sugared drink intake (estimated β = 0.06; 95% CI [0.01, 0.10], p = 0.0136) and maternal BMI (estimated β = 0.03; 95% CI [0.02, 0.04], p < 0.0001) were associated with BMI z-score (adj. R² = 0.2084), independent of other individual and family characteristics. Physical activity, total sugared drink intake and sleep duration were associated with glycemia and non-HDL cholesterol, independent of child BMI z-score. However, irrespective of obesity severity, little of the variance (0.86-11.1%) in cardiometabolic health indicators was explained by individual modifiable health behaviors.

CONCLUSIONS

Physical activity, total sugared drink intake and hours spent sleeping were related to anthropometric and some cardiometabolic health indicators in children entering pediatric weight management programs. This highlights the importance of these modifiable health behaviors on multiple health indicators in children with obesity.

The 24-h Movement Compositions in Weekday, Weekend Day or Four-Day Periods Differentially Associate with Fundamental Movement Skills

The aim of this study was to investigate the relationship between weekday, weekend day and four-day physical activity (PA) behaviours and fundamental movement skills (FMS) in British preschool children from a low socio-economic status background using compositional data analysis (CoDA). One hundred and eighty-five preschool children aged 3-4 years provided objectively assessed PA and sedentary behaviour (SB) data (GENEActiv accelerometer) and FMS (TGMD-2). The association of 24-h movement behaviours with FMS was explored using CoDA and isotemporal substitution (R Core Team, 3.6.1). When data were considered compositionally (SB, light PA (LPA), moderate and vigorous PA (MVPA)) and adjusted for age, BMI and sex, the weekday-derived composition predicted total motor competence (r2 = 0.07), locomotor (r2 = 0.08) and object control skills (r2 = 0.09); the weekend day-derived composition predicted total motor competence (r2 = 0.03) and object control skills (r2 = 0.03), the 4-day-derived composition predicted total motor competence (r2 = 0.07), locomotor (r2 = 0.07) and object control skills (r2 = 0.06) (all p < 0.05). Reallocation of 5 min of LPA at the expense of any behaviour was associated with significant improvements in total motor competence, locomotor and object control skills; for weekend-derived behaviours, MVPA was preferential. Considering movement behaviours over different time periods is required to better understand the effect of the 24-h movement composition on FMS in preschool children.

Phenome-wide investigation of the causal associations between childhood BMI and adult trait outcomes: a two-sample Mendelian randomization study

Background

Childhood obesity is reported to be associated with the risk of many diseases in adulthood. However, observational studies cannot fully account for confounding factors. We aimed to systematically assess the causal associations between childhood body mass index (BMI) and various adult traits/diseases using two-sample Mendelian randomization (MR).

Methods

After data filtering, 263 adult traits genetically correlated with childhood BMI (P < 0.05) were subjected to MR analyses. Inverse-variance weighted, MR-Egger, weighted median, and weighted mode methods were used to estimate the causal effects. Multivariable MR analysis was performed to test whether the effects of childhood BMI on adult traits are independent from adult BMI.

Results

We identified potential causal effects of childhood obesity on 60 adult traits (27 disease-related traits, 27 lifestyle factors, and 6 other traits). Higher childhood BMI was associated with a reduced overall health rating (β = − 0.10, 95% CI − 0.13 to − 0.07, P = 6.26 × 10⁻¹¹). Specifically, higher childhood BMI was associated with increased odds of coronary artery disease (OR = 1.09, 95% CI 1.06 to 1.11, P = 4.28 × 10⁻¹¹), essential hypertension (OR = 1.12, 95% CI 1.08 to 1.16, P = 1.27 × 10⁻¹¹), type 2 diabetes (OR = 1.36, 95% CI 1.30 to 1.43, P = 1.57 × 10⁻³⁴), and arthrosis (OR = 1.09, 95% CI 1.06 to 1.12, P = 8.80 × 10⁻⁹). However, after accounting for adult BMI, the detrimental effects of childhood BMI on disease-related traits were no longer present (P > 0.05). For dietary habits, different from conventional understanding, we found that higher childhood BMI was associated with low calorie density food intake. However, this association might be specific to the UK Biobank population.

Conclusions

In summary, we provided a phenome-wide view of the effects of childhood BMI on adult traits. Multivariable MR analysis suggested that the associations between childhood BMI and increased risks of diseases in adulthood are likely attributed to individuals remaining obese in later life. Therefore, ensuring that childhood obesity does not persist into later life might be useful for reducing the detrimental effects of childhood obesity on adult diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13073-021-00865-3.

The relationship between the home environment and child adiposity: a systematic review

BACKGROUND

Extensive research has demonstrated the role of the Home Environment (HE) in shaping children's energy balance behaviours. Less is known about direct relationships with bodyweight. This review examines associations between the social and physical aspects of three pre-defined Home Environment domains (food, physical activity and media) and adiposity measures in children ≤12 years.

METHODS

Six electronic databases (PubMed, Medline, EBSCO CINAHL, EMBASE, Web of Science, PsycInfo) were systematically searched up to October 2020. Studies reporting at least one physical and/or social aspect of the food, physical activity and/or media domains of the Home Environment in relation to child adiposity outcomes were included (n = 62).

RESULTS

Most studies examined one (n = 41) or two domains (n = 16). Only five studies assessed all three domains of the Home Environment. Most consistent relationships were observed for physical aspects of the home media environment; with greater availability of electronic devices associated with higher child adiposity (21/29 studies). Findings were less consistent for the smaller number of studies examining physical aspects of the home food or physical activity environments. 8/15 studies examining physical food environments reported null associations with adiposity. Findings were similarly mixed for physical activity environments; with 4/7 reporting null associations, 2/7 reporting negative associations and 1/7 reporting positive associations between access to physical activity equipment/garden space and adiposity. Fewer studies assessed social aspects (e.g. caregiver modelling or limit setting) of the Home Environment in relation to child adiposity and findings were again mixed; 9/16 media environment, 7/11 food environment and 9/13 physical activity environment studies reported null associations with child adiposity outcomes.

CONCLUSIONS

The home media environment was most consistently associated with adiposity in childhood. Findings were less consistent for the home food and physical activity environments. Greater agreement on definitions and the measurement of the obesogenic home environment is required in order to clarify the strength and direction of relationships with child adiposity. Robust longitudinal research using comprehensive measures of the holistic home environment is needed to better identify which aspects contribute to excess weight gain in childhood.

TRIAL REGISTRATION

PROSPERO Systematic review registration number:  CRD42018115139 .

Presenting Health Status in Children Using a Radar Plot

BACKGROUND

To try out the feasibility of presenting the health status of children 6 to 12 years old by using radar plots.

METHODS

With data from the Health Oriented Pedagogical Project (HOPP) we have described the health status for 1340 children aged 6 to 12 years. We collected or calculated: stature, body mass, waist circumference, waist to height ratio, high density lipoprotein (HDL) and total cholesterol concentration, blood pressure, accelerometer assessed physical activity, endurance interval running performance, and quality of life. Pertinent variables were presented through a radar plot for both individual cases and groups.

RESULTS

The boys showed better endurance and recorded more moderate to vigorous physical activity than the girls. The activity level dropped from age 6 to age 12 for both sexes. The girls showed a lower systolic blood pressure compared with boys. Self-rated quality of life was high among boys and girls.

CONCLUSIONS

This cohort showed good health and the radar plot made it easy to visualise health status for groups and individuals.

Sleep and obesity among children: A systematic review of multiple sleep dimensions

The objectives were to systematically investigate the multiple dimensions of sleep and their association with overweight or obesity among primary school-aged children. CINHAL, PsycINFO, SPORTDiscus, Medline, Cochrane, Embase, and PubMed databases were searched for papers reporting on an association between children's sleep and weight status. Studies on clinical populations, published in languages other than English, without objectively measured weight status, or where weight status was reported outside the outlined age bracket (5-13 years) were excluded. A total of 34  248 citations were extracted from our systematic search protocol, of which 112 were included for detailed review. Compared with sleep duration, of which 86/103 articles found a significant inverse association between sleep duration and measured weight status, few studies examined other dimensions of sleep, such as quality, efficiency and bed/wake times, and relationship with weight status. Where studies existed, variation in defining and measurement of these dimensions restricted comparison and potentially influenced discrepancies across results. Overall, the findings of this review warrant the need for further research of the outlined dimensions of sleep. Future research would benefit from clarity on definitions across the different dimensions, along with the use of valid and reliable tools.

SEDENTARY BEHAVIOR AND CARDIOVASCULAR RISK IN CHILDREN: A SYSTEMATIC REVIEW

ABSTRACT In recognition of the increasing time spent in sedentary activities in modern life, an emerging area of study linking sedentary time to health has highlighted its role in the development of chronic diseases. Therefore, the objective of this systematic review was to investigate the indicators and characteristics of sedentary behavior associated with cardiovascular risk factors in children and adolescents. The databases SciVerse Scopus, MEDLINE®/PubMed and LILACS were selected as a source of reference, using the associated terms “sedentary lifestyle” or “sedentary behavior” or “sedentary” AND “cardiovascular diseases” AND “child or adolescent” to identify studies published from January 2006 to March 2019. The methodological quality of the studies was evaluated and a score was assigned. Fifty articles were included in this review at the end. Extensive sedentary time, especially greater screen and TV exposure time, were associated with cardiovascular risk factors. In addition, the accumulation of prolonged sedentary bouts with few breaks in sedentary time tended to compromise the cardiometabolic profile. These findings highlight the importance of differentiating and considering these various indicators and characteristics of sedentary behavior. Further studies are needed to elucidate the multiple and overlapping facets of sedentary behavior and their relationship with health, and to encourage the development of evidence-based recommendations for this population. Level of Evidence I; Systematic Review of Level I Studies.

Sleep, energy balance, and meal timing in school-aged children

OBJECTIVE

To determine associations among objectively-measured nocturnal sleep time, bedtime and obesogenic behaviors, including dietary intake, timing of intake, and physical activity, in a diverse sample of school-aged children who presented for behavioral treatment to enhance sleep duration.

METHODS

Eighty-seven children (8-11 y, 66.7% female, zBMI: 0.86 ± 1.0) who self-reported sleeping <9.5 h/night were studied for one week using wrist actigraphy to estimate sleep; hip-worn accelerometers to measure physical activity; and 24 h dietary recalls to capture dietary intake and meal timing. Pearson and Spearman's rho correlations and linear regressions controlling for age, gender and race were used for statistical analyses.

RESULTS AND CONCLUSION

Mean bedtime was 10:31 PM (±58.2 min) and mean nocturnal sleep time was 7.7 h (±37.5 min). Although later bedtime was associated with shorter sleep time (r = -0.61, p < 0.001), the two variables were differentially related to obesity risk factors. Later bedtime, but not sleep time, correlated with greater daily fat intake, later first meal of the day, and greater after-dinner intake (all p < 0.05). Nocturnal sleep time, but not bedtime, correlated with zBMI (p = 0.04). Both sleep time and later bedtime were associated with a later last meal of the day (all p < 0.05). Findings remained consistent after controlling for demographic factors. In short-sleeping school-aged children, bedtime may be more predictive of dietary obesity risk factors whereas sleep duration may be more predictive of zBMI. Results suggest that health providers should consider both bedtime and sleep duration for reducing obesity risk in children.

CLINICAL TRIAL

Enhancing Sleep Duration: Effects on Children's Eating and Activity Behaviors, NCT03186508, https://clinicaltrials.gov/ct2/show/NCT03186508.

Accelerometer-based physical activity levels, fundamental movement skills and weight status in British preschool children from a deprived area

Preschool children are recommended to participate in a minimum of 180-min physical activity (PA) per day to enhance their development and overall health. Low PA and increased obesity are thought to be linked to low mastery of fundamental movement skills (FMS) in preschool children. This study sought to investigate whether FMS influences PA levels and weight status in preschool children, in an area of low socioeconomic status. Secondary aims of this study were to determine whether gender or day of the week affected the primary outcomes. One hundred eighty-five preschool children aged 3-4 years old, participated in the study. FMS proficiency was determined using the Test of Gross Motor Development-2. PA was determined using triaxial accelerometry over a 4-day period. None of the samples met the recommended 180 min of PA. There were no significant differences in PA or weight status between preschool children with high, medium or low FMS mastery (P < 0.05). There were also no significant correlations between overall FMS and moderate to vigorous PA during the week or weekend days.Conclusion: Girls scored significantly greater at the hop, leap, and skip (locomotor skills) and the boys significantly higher at the kick (object control) (P < 0.05). There were no significant differences in PA or weight status between preschool children with high, medium, or low FMS mastery, possibly because FMS mastery had not developed to a high enough level to affect PA and FMS are considered independent of physical fitness and physical features, such as weight and height. What is Known: •FMS are commonly developed in early childhood, providing the building blocks for future motor skills, good health and lifelong PA. •No study to date has measured FMS, PA levels and weight status in preschool children, to determine whether FMS competency influences PA levels and weight status in preschool children, in an area of low SES. What is New: •FMS competency did not appear to influence the level of PA or weight status in this sample of UK preschool children from a low SES area. •PA and FMS may not be fully established and consequently not strongly linked at the ages of 3-4 years, therefore, the preschool years could be influential in providing a window to maximise input of good/optimal development of motor competence before the proficiency barrier sets in and we need remedial intervention.

Multiple lifestyle behaviours and overweight and obesity among children aged 9-11 years: results from the UK site of the International Study of Childhood Obesity, Lifestyle and the Environment

OBJECTIVES

The purpose of this study was to explore the independent associations between multiple lifestyle behaviours (physical activity, sleep, screen time (ST) and diet) and overweight and obesity in UK children. The second objective was to compare body mass index (BMI) z-score between children who meet health guidelines for each lifestyle behaviour and those who do not and to explore the impact of interactions between lifestyle behaviours on BMI z-score.

DESIGN, SETTING AND PARTICIPANTS

Cross-sectional study on children aged 9-11 years in the UK (n=374).

OUTCOME MEASURES

Participants were classified as overweight or obese using the WHO BMI cut-points. Moderate-to-vigorous intensity physical activity (MVPA) and sleep duration were measured using an ActiGraph GT3X+ accelerometer, whereas ST and dietary habits were assessed using questionnaires. Multilevel multiple logistic regression was employed to analyse associations between lifestyle behaviours and overweight/obesity. Participants were then categorised according to whether or not they met specific health criteria for MVPA, ST, sleep and diet. Multilevel multiple linear regression was used to compare these groupings on the outcome of BMI z-score and interactions were explored.

RESULTS

MVPA and longer sleep duration were associated with lower odds of overweight or obesity, whereas ST and a healthy diet score were associated with increased odds of overweight/obesity. No association was found for an unhealthy diet score. Meeting MVPA guidelines was significantly associated with a lower BMI z-score in all models, and significant two-way interactions were observed for physical activity and sleep, ST and sleep, and physical activity and diet.

CONCLUSIONS

MVPA, sleep and ST are important lifestyle behaviours associated with overweight/obesity among children. More research is required to confirm the role of diet on adiposity and such work would benefit from objective assessment. Overall, this work suggests that strategies aimed at improving compliance with health guidelines are needed.

TRIAL REGISTRATION NUMBER

NCT01722500.

Establishing Waist-to-Height Ratio Standards from Criterion-Referenced BMI Using ROC Curves in Low-Income Children

The purpose of this study was to establish health-related waist-to-height ratio (WHtR) cut-points associating with FITNESSGRAM's body mass index (BMI) criterion-referenced standards in low-income children. A secondary aim was to examine the classification agreement between the derived WHtR cut-points and various cardiometabolic blood markers using current recommendations. Participants were 219 children from low-income schools (mean age = 10.5 ± 0.6 years). Waist circumference, height, weight, and cardiometabolic blood markers were collected in a fasting state before school hours. Receiver operating characteristic (ROC) curves were used to determine WHtR cut-points that associated with a child meeting FITNESSGRAM's age- and sex-specific criterion-referenced standards for BMI. The derived WHtR cut-point was 0.50 (AUC = 0.89, p < 0.001; sensitivity = 0.86, specificity = 0.82, and accuracy = 84.3%). Classification agreement using the derived WHtR cut-point with various blood marker standards was statistically significant but considered weak to fair (kappa 0.14-0.34, agreement = 59%-67%, and p < 0.01). The WHtR cut-point of 0.50 can be used with strong accuracy to distinguish low-income children who met FITNESSGRAM's criterion-referenced standards for body composition; however, the evidence was weaker for its use in distinguishing low-income children meeting specific cardiometabolic blood marker recommendations.

Cardiorespiratory fitness is positively associated with a healthy dietary pattern in New Zealand adolescents

OBJECTIVE

To examine the association between cardiorespiratory fitness and dietary patterns in adolescents.

DESIGN

Food choice was assessed using the validated New Zealand Adolescent FFQ. Principal components analysis was used to determine dietary patterns. Trained research assistants measured participants' height and body mass. Cardiorespiratory fitness was assessed in a subset of participants using the multistage 20 m shuttle run. The level and stage were recorded, and the corresponding VO2max was calculated. Differences in mean VO2max according to sex and BMI were assessed using t tests, while associations between cardiorespiratory fitness and dietary patterns were examined using linear regression analyses adjusted for age, sex, school attended, socio-economic deprivation and BMI.

SETTING

Secondary schools in Otago, New Zealand.

SUBJECTS

Students (n 279) aged 14-18 years who completed an online lifestyle survey during a class period.

RESULTS

Principal components analysis produced three dietary patterns: 'Treat Foods', 'Fruits and Vegetables' and 'Basic Foods'. The 279 participants who provided questionnaire data and completed cardiorespiratory fitness testing had a mean age of 15·7 (sd 0·9) years. Mean VO2max was 45·8 (sd 6·9) ml/kg per min. The 'Fruits and Vegetables' pattern was positively associated with VO2max in the total sample (β=0·04; 95%CI 0·02, 0·07), girls (β=0·06; 95% CI 0·03, 0·10) and boys (β=0·03; 95% CI 0·01, 0·05).

CONCLUSIONS

These results indicate that increase in cardiorespiratory fitness was associated with a healthier dietary pattern, suggesting both should be targeted as part of a global lifestyle approach. Longitudinal studies are needed to confirm this association in relation to health outcomes in New Zealand adolescents.

Prevalence and risk factors of abdominal obesity in Polish rural children

Secular trends of body mass index (BMI) and waist circumference indicate greater increase in abdominal obesity compared to general obesity. Determinants of obesity described by BMI are relatively well documented in various populations, unlike abdominal obesity described by waist-to-height ratio (WHtR). The aim of the study was to determine prevalence and abdominal obesity (WHtR) risk factors in a cohort of 3048 rural children aged 7-12 years from southern Poland. Biological, socio-demographic and lifestyle factors were analysed, and odds ratio and 95% confidence interval were calculated using a logistic regression analysis. The prevalence of abdominal obesity in rural boys and girls in the sample was 11% and 9% respectively. Obesity in both parents, irregular breakfasts, irregular meals during the day and regularly consumed tea were significant factors of abdominal obesity risks in rural girls. Being the only child, low number of people in a household, obesity in both parents, high energy-dense food index and no exercise significantly increased the risk of abdominal obesity in rural boys. The study demonstrated tendencies similar to other European countries in the prevalence of abdominal obesity among sexes. Lifestyle behaviours should be changed and adapted to each sex since risk factors differ between the sexes and indicate higher eco-sensitivity in boys.

Dietary patterns and breakfast consumption in relation to insulin resistance in children. The Healthy Growth Study

OBJECTIVE

Insulin resistance is a significant cross-point for the manifestation of several chronic diseases in children and adults. The aim of the present study was to investigate the possible relationship of certain dietary patterns and breakfast consumption habits with insulin resistance in children.

SUBJECTS

A representative sample of 1912 schoolchildren (aged 9-13 years) participated in a cross-sectional epidemiological study, the Healthy Growth Study, which was initiated in May 2007 and completed in June 2009.

SETTING

It was conducted in seventy-seven primary schools in four large regions in Greece.

DESIGN

Dietary intake, breakfast consumption, anthropometric and physical examination data, biochemical indices and socio-economic information collected from parents were assessed in all children. Principal components analysis was used to identify dietary patterns.

RESULTS

A dietary pattern of increased consumption of margarine, sweets (candies, lollipops, jellies, traditional fruit in heavy syrup) and savoury snacks (chips, cheese puffs and not home-made popcorn) was associated with homeostasis model assessment of insulin resistance index (HOMA-IR; β = 0·08, P < 0·001) in multivariate models. Children in the third tertile of this dietary pattern had a 2·51 (95 % CI 1·30, 4·90) times higher risk of insulin resistance (HOMA-IR > 3·16) than those in the first tertile. Breakfast consumption had an inverse correlation with insulin resistance, but the correlation lost its significance after adjustments for waist circumference, birth weight, parental BMI and socio-economic status.

CONCLUSIONS

Increased consumption of margarine, sweets and savoury snacks, which is a common dietary pattern in childhood, was positively associated with insulin resistance, while breakfast consumption had an inverse association with HOMA-IR, in schoolchildren (aged 9-13 years). Identification of dietary behaviours that might affect insulin resistance in children offers valuable advice in cardiometabolic risk prevention strategies.

RISK FACTORS FOR ABDOMINAL OBESITY IN CHILDREN AND ADOLESCENTS FROM CRACOW, POLAND (1983–2000)

The aim of this study was to determine abdominal obesity risk factors in two successive cohorts of children and adolescents aged 4–18 from Cracow, Poland, examined during the years of political transformation. The influence of biological, socio-demographic and lifestyle factors on abdominal obesity was analysed by calculating odds ratios and 95% confidence intervals using logistic regression analysis. It was found that for girls obesity in both parents (OR=4.31; 95% CI 1.73–20.70) and high birth weight (OR=1.78; 95% CI 1.12–2.82) were significant risk factors for abdominal obesity in the 1983 cohort. In the 2000 cohort obesity in both parents for boys and girls (boys: OR=5.85; 95% CI 1.36–25.10; girls: OR=4.82; 95% CI 1.17–19.77), low level of parental education in girls (OR=2.06; 95% CI 1.15–3.69), having only one son (OR=1.96; 95% CI 1.36–3.40), parents' smoking habits in girls (OR=2.94; 95% CI 1.46–5.91) and lack of undertaking physical activity in sport clubs in boys (OR=6.11; 95% CI 1.46–25.47) were significant abdominal obesity risk factors. Higher number of hours of leisure time physical activity (OR=0.89; 95% CI 0.81–0.97) significantly lowered the risk of abdominal obesity in boys in the 2000 cohort. The greater differentiation of abdominal obesity risk factors in the 2000 cohort in comparison to the 1983 cohort may have resulted from the social and economic changes taking place in Poland at the end of the 20th century.

Sedentary Behavior and Health Outcomes in Children and Adolescents

The purpose of this review was to summarize findings from epidemiological studies that determined if sedentary behavior was associated with obesity, metabolic risk factors, and cardiorespiratory fitness in children and adolescents. We noted if studies adjusted for moderate-to-vigorous physical activity (MVPA), dietary intakes, and/or sleep duration. Articles were identified through PubMed using the search terms: (sedentary OR sitting OR television) AND (adiposity OR blood pressure OR body mass index OR cardiometabolic OR metabolic risk OR waist circumference). The search was limited to ages 6 to 18 years, humans, and published between January 1, 2008 and September 26, 2012. Cross-sectional and longitudinal studies observed associations between more sedentary behavior, especially screen-based sedentary behavior, and measures of obesity; and most associations were independent of MVPA and dietary intake. Cross-sectional and longitudinal studies reported associations between screen-based sedentary behavior and lower cardiorespiratory fitness, and most associations were independent of MVPA and obesity. Cross-sectional studies observed associations between more screen-based and objectively measured sedentary behavior and lower insulin sensitivity; and most associations were independent of MVPA and obesity. There was little-to-no evidence that sedentary behavior was associated with increased blood pressure and increased blood lipids.

Dieting status influences associations between dietary patterns and body composition in adolescents: a cross-sectional study

Background

Associations between food choice and body composition in previous studies of adolescents have been inconsistent. This may be due to the body composition measures used, or these associations may be affected by the dieting status of adolescents. The objective of this study was to investigate the association between dietary patterns and body composition in adolescents, and determine if these associations are moderated by dieting status.

Methods

Information on food consumption and current dieting status was collected, using a web-based survey, in 681 adolescents (mean age 15.8 (SD 0.9) years) from schools in Otago, New Zealand. Non-dieters were defined as those reporting not being on a diet as they were “happy with their weight”. Principal components analysis (PCA) was used to determine dietary patterns. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), fat mass index (FMI), and fat-free mass index (FFMI) were examined as outcomes. Generalized estimating equations were used to examine associations between dietary patterns and body composition.

Results

PCA produced three dietary patterns: ‘Treat Foods’, ‘Fruits and Vegetables’, and ‘Basic Foods’. A standard deviation increase in ‘Basic Foods’ was associated with a 3.58% decrease in FMI (95%CI −6.14, -0.94) in the total sample. When separate sex analysis was undertaken significant negative associations were found in boys only, between the ‘Basic Food’ score and WC, WHtR, FMI, and FFMI, while the ‘Fruits and Vegetables’ pattern was negatively associated with FMI. Associations between ‘Treat Foods’ and BMI, WC, and WHtR in non-dieters were positive, while these associations were negative for all other participants.

Conclusions

Significant associations were found between dietary patterns and indices of both central and total adiposity, but not BMI. Therefore using only BMI measures may not be useful in this age group. Since our results were significant for boys and not girls, nutrition messages designed to prevent obesity may be particularly important for adolescent boys. As an interaction between dieting status and ‘Treat Foods’ existed, future studies should also explore the role of dieting when investigating food choice and body composition.