Normal Weight Adolescents Research Articles

Screening and Identification of Putative Long Non-Coding RNA in Childhood Obesity: Evaluation of Their Transcriptional Levels.

Background and Methods: Long non-coding RNAs (LncRNAs) and microRNAs are involved in the pathogenesis of obesity, a multifactorial disease that is characterized by inflammation, cardiometabolic complications, and increased cancer risk among other co-morbidities. The up/down regulation of LncRNAs and microRNAs may play an important role in this condition to identify new diagnostic/prognostic markers. The aim of the study was to identify circulating inflammatory LncRNAs in obese adolescents (n = 54) and to evaluate whether their expression behaved differently compared to normal-weight adolescents (n = 26). To have a more complete insight, the expression of some circulating miRNAs that are linked to obesity (miR-33a, miR-223, miR-142, miR-199a, miR-181a, and miR-4454) were also analyzed. Results: LncRNAs and miRNAs were extracted simultaneously from plasma samples and amplified by Real-Time PCR. Among the 86 LncRNAs that were analyzed with custom pre-designed plates, only four (RP11-347E10.1, RP11-10K16.1, LINC00657, and SNHG12) were amplified in both normal-weight and obese adolescents and only SNHG12 showed significantly lower expression compared to the normal-weight adolescents (p = 0.026). Circulating miRNAs showed a tendency to increase in obese subjects, except for miR-181a expression. LncRNAs and miRNAs correlated with some clinical and metabolic parameters. Conclusions: Our results suggest the importance of these new biomarkers to better understand the molecular mechanisms of childhood obesity and its metabolic disorder.

Predictive Validity of Image-Based Motivation-to-Eat Visual Analogue Scales in Normal Weight Children and Adolescents Aged 9-14 Years.

Paper-based motivation-to-eat visual analogue scales (VASs) developed for adults are widely used in the pediatric age range. The VAS is comprised of four domains: hunger, fullness, desire to eat, and prospective food consumption. The purpose of the present study was to determine agreement between the traditional paper-based VAS and a novel digital VAS (with and without images), as well as the novel digital VAS’s predictive validity for subsequent food intake (FI) in 9–14-year-old children and adolescents. Following an overnight fast and 3 h after consuming a standardized breakfast at home, children and adolescents (n = 17) completed three different VAS instruments (VASpaper, VASimages, VASno-images) in a randomized order at five time-points: 0 min (baseline), 5 min (immediately after consuming a 147 kcal yogurt treatment), 20 min, 35 min (immediately before an ad libitum lunch), and 65 min (immediately post ad libitum lunch). All three instruments were comparable, as shown by low bias and limits of agreement on Bland–Altman plots, moderate to excellent intraclass correlation coefficients for all domains at all time-points (ICC = 0.72–0.98), and no differences between the incremental area under the curve for any of the domains. All three instruments also showed good predictive validity for subsequent FI, with the strongest relationship observed immediately before the ad libitum lunch (p = 0.56–0.63). There was no significant association between subjective thirst and water intake, except with VASno-images at baseline (r = 0.49, p = 0.046). In conclusion, the present study suggests that a novel image-based digital VAS evaluating motivation-to-eat is interchangeable with the traditional paper-based VAS, and provides good predictive validity for next-meal FI in 9–14-year-old normal weight children and adolescents.

Factors associated with normal-weight obesity in adolescents.

A new phenotype of obesity has been studied: normal-weight obesity (NWO), which describes individuals with normal-weight by BMI and excess body fat. Despite normal-weight, individuals with NWO have a higher cardiometabolic risk. There is still a gap in the literature on the subject, especially in adolescents, as studies with this population are scarce. This study aims to investigate the sociodemographic factors, family history of chronic non-communicable diseases, body perception, lifestyle and food consumption associated with NWO in adolescents. This is a cross-sectional study, with 506 normal-weight adolescents aged 10–19 years, of both sexes. Weight and height were obtained, and BMI/age was calculated. Body fat analysis was performed using dual-energy X-ray absorptiometry. Sociodemographic data, level of physical activity, food consumption, body self-perception and lifestyle habits were also obtained. Logistic regression with hierarchical approach was used to analyse the associations. The odds of NWO are greater with age (OR = 1·14; 95 % CI = 1·04, 1·26), lower in male adolescents (OR = 0·21; 95 % CI = 0·11, 0·41) and higher in those with a history of familial dyslipidemia (OR = 1·81; 95 % CI = 1·01, 3·28). Adolescents satisfied with their body (OR = 0·30; 95 % CI 0·16, 0·56) and physically active (OR = 0·44; 95 % CI = 0·24, 0·81) have a lower odds of NWO, compared with the others. In addition, it was observed that the odds of NWO is greater among adolescents who use sweeteners (sugar substitutes) (OR = 3·84; 95 % CI = 1·70, 8·65). The factors associated with NWO were female sex, older age, positive family history of dyslipidemia, lower body satisfaction, lower level of physical activity and greater use of sweeteners.

Relationship of sleep quality with screen-based sedentary time and physical activity in adolescents - the moderating effect of body mass index.

To analyze the association of sleep quality with reported screen-based sedentary time and reported physical activity, among overweight adolescents. Adolescents aged 10 to 17years enrolled in public and private schools were included. Data collection was carried out during the school semesters of 2014-2015 and participants who did not participate in all evaluations were excluded. Sleep quality and physical activity were assessed by validated questionnaires. Screen-based sedentary time was assessed by self-reported mean daily hours spent on television, computer, smartphone/tablet, and videogames. Body mass index was objectively measured and adolescents were classified into normal weight and overweight according to cutoff points for age and sex. Multiple linear regression models adjusted by covariates (age, sex, ethnicity, and socioeconomic status) were used to analyze the relationship between variables. A total of 1008 adolescents were assessed, with a mean age of 13.2 ± 2.4years and a mean body mass index of 20.4 ± 4.3kg/m2. Overweight was observed in 28.0% of sample, while 53.0% reported non-white ethnicity. Self-reported screen-based sedentary time was significantly related to poor sleep quality in adolescents (β = 0.116, p = 0.005), remaining significant only in those who were normal weight (β = 0.101, p = 0.007) in sensitivity analysis. Self-reported physical activity showed no relationship with sleep quality in both normal weight and overweight adolescents. Self-reported screen-based sedentary time was associated with poor sleep quality in adolescents, mainly among those with normal weight. The time spent on screen-based sedentary activities can impair sleep quality even in normal weight adolescents.

Eating behaviors and alexithymic features of obese and overweight adolescents.

In this study, eating behaviors and alexithymia levels in obese adolescents were investigated. Relationships between alexithymia, eating behavior and insulin resistance were studied. The patient group consisted of 87 obese adolescents or overweight adolescents (O + OW). The comparison group consisted of 101 normal weight adolescents (N). Alexithymia Questionnaire for Children, Dutch Eating Behavior Questionnaire, and Revised Child Anxiety and Depression Scale-Child Version, are used for assessing adolescents. The homeostasis model assessment-estimated insulin resistance was calculated to determine insulin resistance. Alexithymia Questionnaire for Children scores were significantly higher in O + OW than N (P = 0.009). Both emotional and restrained eating scores are higher in O + OW (P < 0.001 for both). On the other hand, external eating scores were not significantly different. In O + OW, external eating was positively associated with homeostasis model assessment-estimated insulin resistance (r: 035, P = 0.006), but is not associated with fasting blood glucose and the hemoglobin A1c (HbA1c) (r: -0.05, P = 0.62; r: -0.05, P = 0.73). Regression analysis showed that restrained and emotional eating were predictors of O + OW (B: 0.1, P < 0.001; B: 0.06, P = 0.001). Emotional eating was positively correlated with the Alexithymia Questionnaire for Children and Revised Child Anxiety and Depression Scale-Child Version in O + OW (r: 0.29, P = 0.008; r: 0.48, P < 0.001). Obese and overweight adolescents were more alexithymic than normal weight adolescents. Alexithymia scores were also positively associated with emotional eating. On the other hand, alexithymia was not a predictor of obesity/overweight. Restrained and emotional eating were predictors of obesity/overweight. Emotional and restrained eating were more common in obese and overweight adolescents than normal-weight adolescents. External eating is not significantly associated with obesity but is related to insulin resistance.

The Relationship Between Body Mass Index and Depression, Anxiety, Body Image, and Eating Attitudes in Adolescents in Iran.

Background:The aim of this study was to investigate the relationship between body mass index (BMI) and depression, anxiety, body image, and eating attitudes in 12- to 16-year-old adolescents.Materials and Methods:In this descriptive-analytical study on 437 students in Shahrekord, Iran, selected by two-step random sampling (selection of schools and students), participants were divided into normal weight (BMI: 5–85th), overweight (BMI: 85–95th), and obese (BMI >95th) groups and completed the questionnaires and data were analyzed by SPSS version 23.Results:BMI had a positive correlation with anxiety, depression, and dysfunctional eating attitudes, and negative correlation with body image in adolescents. Mean scores of depression and anxiety in both overweight and obese groups were significantly higher than those in normal weight adolescents but scores of body image and eating attitudes were not different between overweight and normal weight groups.Conclusion:Obesity and overweight may have adverse effects on mental health of adolescents and more attention to psychological aspect of obesity can help us to provide better health services to overweight and obese adolescents.

Deviating glucose results in an international dual-center study. A root cause investigation.

During a dual-center study on obese and normal weight children and adolescents, focusing on glucose metabolism, we observed a marked difference in glucose results (N = 16,840) between the two sites, Salzburg, Austria and Uppsala, Sweden (P < 0.001). After excluding differences in patient characteristics between the two populations as cause of this finding, we investigated other preanalytic influences. Finally, only the tubes used for blood collection at the two sites were left to evaluate. While the Vacuette FC-Mix tube (Greiner Bio-One, Kremsmünster, Austria) was used in Uppsala, in Salzburg blood collections were performed with a lithium heparin tube (LH-Monovette, Sarstedt, Germany). To prove our hypothesis, we collected two blood samples in either of these tubes from 51 children (Salzburg N = 27, Uppsala N = 24) and compared the measured glucose results. Indeed, we found the suspected bias and calculated a correction formula, which significantly diminished the differences of glucose results between the two sites (P = 0.023). Our finding is in line with those of other studies and although this issue should be widely known, we feel that it is widely neglected, especially when comparing glucose concentrations across Europe, using large databases without any information on preanalytic sample handling.

Visceral adiposity index performed better than traditional adiposity indicators in predicting unhealthy metabolic phenotype among Chinese children and adolescents

The relationship between visceral adiposity index (VAI) and unhealthy metabolic phenotype remained unclear in children and adolescents. This study aimed to investigate their association and compared the ability of VAI and traditional adiposity indicators (body mass index, waist circumference and waist-to-height ratio) to predict metabolically unhealthy phenotype among normal-weight, overweight and obese children and adolescents. In this cross-sectional study, 1722 children and adolescents aged 12–18 years were selected by cluster random sampling, underwent a questionnaire survey, physical examination and biochemical tests. Participants were divided into four phenotypes according to the combination of the weight status determined by body mass index (BMI) and metabolic syndrome components. Receiver operating characteristic (ROC) analysis and multivariate logistic regression were used to compare the predictive capacity between VAI and traditional adiposity indicators and their relationship with metabolically unhealthy phenotype. We found that VAI had better performance in predicting metabolically unhealthy phenotype than traditional adiposity indicators, the area under the receiver-operating characteristic curve (AUC) were 0.808 and 0.763 for boys and girls with normal-weight, 0.829 and 0.816 for boys and girls with overweight and obese (all P < 0.001). VAI was most strongly related to metabolically unhealthy phenotype whether or not to adjust the age, the adjusted OR and 95%CI was 6.15 (4.13–9.14) in boys with normal weight, and 5.90 (3.06–11.36), 4.95 (2.35–10.41) in boys and girls with overweight and obese, respectively (all P < 0.001). Our findings suggested VAI could be used as a comprehensive predictor to identify unhealthy metabolic phenotype in children and adolescents.

Is there a Relationship between the Characteristics and Attitudes of Adolescents with Premarital Sex?

Background: Premarital sex is one of the high-risk behaviors of adolescents today. The characteristics of adolescents can also be a triggering factor for premarital sex. The purpose of this study was to analyze the relationship between characteristics and attitudes of adolescents towards premarital sex in East Java Province.Methods: This is a quantitative research with a cross sectional research design. The data used were taken from Program Performance and Accountability Survey (2018) on adolescents aged 15-24 years in East Java Province. The sample of this study was 2796 adolescents after normal weight adolescents were carried out. The dependent variable in this study is the attitude of adolescents, while the independent variables are place of residence, age, gender, education, and economic status. Data collection using smartphones and instruments that refer to the IDHS and PMA. The data were analyzed descriptively and tested using chi-square with a significance level of 0.05.Result and Conclusion: The results showed that the characteristics associated with the attitude of female adolescent was the place of residence with a significance value of 0.026. Age was related to the attitude of male adolescent with a significance value of 0.014. Education was related to the attitude of female adolescent (p-vaue = 0.000) and attitudes of male adolescent (p-value = 0.016). Economic status was related to the attitude of female adolescent (p-value = 0.000) and attitudes of male adolescents (p-value = 0.035). Characteristics had a relationship with adolescent attitudes in conducting pre-primary sex behavior. Therefore, it is necessary to have appropriate efforts to prevent adolescent risk behavior in accordance with the characteristics and needs of today’s youth

Assessment of Eating Habits and Perceived Benefits of Physical Activity and Body Attractiveness among Adolescents from Northeastern Romania

The purpose of this paper was to present the results of the evaluation of 1320 adolescents from 4 high schools in Iaşi, Romania regarding their eating habits and perceived benefits of physical activity and body attractiveness after they completed an anonymous questionnaire. The data analysis was performed using IBM SPSS version 18. The analysis of the nutritional status showed that over 70% of adolescents were of a normal weight. Most of them (63.56%) consumed 3–4 meals/day, with breakfast being the most skipped meal (60.53%). Compared with the boys, the girls consumed fewer whole grains, dairy products, and meat, but the girls consumed fruits and vegetables in approximately the same percentage. The adolescents studied consumed more fruits than vegetables, but the servings of fruits and vegetables consumed were not sufficient in the diets of many adolescents (39.31%). Among the adolescents, 5.68% consumed at least 2 alcoholic drinks daily, and 37.87% consumed caffeine products one or more times per week. Among the boys, 95.20% practiced regular physical activity, and 97.20% of the girls considered that the right nutrition plays a role in the prevention of obesity. The study of the self-perception profile showed that 89.8% of boys and 79.5% of girls considered that they had attractive bodies. According to the BMI, 86.7% of normal-weight adolescents and 84.8% of underweight adolescents considered themselves as having attractive bodies, while this was only considered by 73.5% of overweight and 56.7% of obese adolescents. It is necessary to introduce nutritional education in schools for the improvement of eating habits in children and adolescents. More studies are needed to appreciate the social behaviors (e.g., food intake, physical activity, and recreation time) and then develop interventions and national health programs to promote a healthy lifestyle, particularly healthy eating habits.

Psychopathological Symptoms and Well-Being in Overweight and Underweight Adolescents: A Network Analysis.

Overweight and underweight adolescents have an increased risk of psychological problems and reduced quality of life. We used a network analysis approach on a variety of psychopathology and well-being variables to identify central factors in these populations. The network analysis was conducted on data of 344 overweight adolescents (>90th BMI-percentile) and 423 underweight adolescents (<10th BMI-percentile) drawn from a large community sample (10–19 years) including behavioral and emotional problems (Youth Self-Report), eating disorder risk (SCOFF) and well-being variables (KIDSCREEN). Additionally, psychopathology and well-being scores of overweight and underweight individuals were compared with 1.560 normal weight adolescents. Compared to their normal weight peers, overweight adolescents showed elevated psychopathology and eating disorder risk as well as reduced well-being. Underweight adolescents reported increased levels of internalizing problems but no increased eating disorder risk or reduced well-being. The network analysis revealed that anxious/depressed mood and attention problems were the most central and interconnected nodes for both overweight and underweight subsamples. Among underweight individuals, social problems and socially withdrawn behavior additionally functioned as a bridge between other nodes in the network. The results support psychological interventions focusing on improving mood, coping with negative emotions and tackling inner tension.

Cardiometabolic risk in adolescents with normal weight obesity.

Normal weight obesity (NWO), which is defined by the excess of body fat in normal weight individuals, has been neglected among adolescents, due to their normal weight and young age. Few studies were carried out on the topic with adolescents. To analyze whether the NWO is associated with cardiometabolic risk factors in adolescents. Cross-sectional study, with 506 normal weight adolescents aged 10-19 years, selected in schools in Brazil. Weight, height, waist circumference (WC) and neck circumference were obtained and the body mass index (BMI) and waist/height ratio (WHR) were calculated. Body composition analysis was performed using dual-energy X-ray absorptiometry. The clinical evaluation included lipid and glycid profile, platelets, leukocytes, lymphocytes, monocytes, uric acid and blood pressure, as well as the presence of metabolic syndrome (MS) and its components. NWO was defined by the presence of normal weight, according to BMI for age, and excess body fat (≥25% and ≥30% in males and females, respectively). Logistic regression models were used to analyze associations between normal weight adolescents with and without the NWO phenotype. NWO associated positively with abdominal obesity, analyzed through WC (OR = 1.36;95%CI = 1.27-1.47), WHR (OR = 25.89;95%CI = 10.43-64.26) and android fat (OR = 1.49;95%CI = 1.36-1.63); insulin resistance (OR = 4.09;95%CI = 1.72-9.70), hyperinsulinemia (OR = 3.83;95%CI = 1.50-9.76) and the highest values of the triglycerides-glycemia index (OR = 4.28;95%CI = 1.21-15.08); uric acid (OR = 1.81;95%CI = 1.29-2.55), as well as the changes in LDL (OR = 3.39;95%CI = 1.47-7.81), total cholesterol (OR = 2.77;95%CI = 1.22-6.29), and in at least one (OR = 1.87;95%CI = 1.04-3.37) or two (OR = 6.61;95%CI = 1.45-30.19) components of MS. NWO is associated with the presence of cardiometabolic risk factors in adolescents.

Kvaliteta života i motivacija za vježbanje adolescenata normalne i prekomjerne tjelesne mase

The aim of this study was to examine gender and body-mass index differences in quality of life and exercise motives of adolescents. The sample consisted of 744 first-year high school students from the City of Zagreb. Quality of life was measured with an adapted version of the Kidscreen-27, and exercise motivation with the EMI-2. The results suggest that adolescents experience positive quality of life and their exercise motivation derives from intrinsic and extrinsic motives. Higher levels of male adolescents' quality of life, compared to females', predominantly result from a greater sense of physical well-being, more pleasant emotions and moods, more positive school and family environment, and the ability to plan and spend leisure time. Normal-weight adolescents are more satisfied with their physical activity and health than overweight ones. Male adolescents are more driven by enjoyment, challenge, competition, strength, and social motives (belonging, pressure, and recognition), unlike females, who exercise more because of weight control. Normal-weight adolescents are more motivated for exercise by enjoyment than overweight ones, who are more driven by weight control. The implications of these findings were discussed.

Myocardial Geometry and Dysfunction in Morbidly Obese Adolescents (BMI 35–40 kg/m2)

This study evaluated the preclinical effect of obesity on the ventricular remodeling in adolescents with morbid obesity, and determined if subjects labelled as metabolically healthy obesity (MHO) presented better heart index than those with metabolically unhealthy obesity (MUO). Prospective case-control research of 45 adolescents (14-year-old) with morbid obesity and 25 normal weight adolescents' gender- and age-matched with Tanner stage 4-5. Left ventricle (LV) was evaluated by conventional Doppler echocardiography, tissue Doppler imaging and two-dimensional speckle tracking echocardiography. Compared to normal-weight subjects, adolescents with morbid obesity presented a high percentage of pathological LV geometry (87%; p<0.01), and systolic and diastolic dysfunctions only detected by E/A ratio (2.0 vs 1.7, p<0.01), global longitudinal strain (-21.0% vs -16.5%, p<0.01), and early diastolic strain rate (3.2 vs 2.2, p<0.01). A correlation was found between impaired cardiac index and body mass index (BMI), high blood pressure, hyperglycemia, low HDL-cholesterol and hypertriglyceridemia. BMI and HDL-cholesterol were the most significant independent variables. No significant differences were found in structural and functional cardiac index when MHO and MUO subjects were compared (global longitudinal strain: -17.0% vs -16.4%, p0.79). Morbidly obese adolescents have an abnormal LV geometry, closely related to BMI, and systolic and diastolic LV dysfunctions. Adolescents labelled as MHO, despite exhibiting better BMI and insulin-resistance values, present the same pathological heart changes as MUO.

Effect of Physical Activity on Adolescent Obesity Status over Time: A Latent Growth Modeling Approach.

This study aims to examine the longitudinal influence of physical activity (PA) on obesity among normal-weight adolescents in South Korea. A total of 1347 data samples from the Korean Children and Youth Panel Survey from 2011 to 2014 were used. Latent growth modeling was applied. PA was assessed by the hours spent on PA during physical education (PE) classes in the last week. Body mass index for age was considered to determine obesity status. PA during PE positively predicted the intercept of obesity status, but it was not associated with the slope of obesity status. Although a longitudinal effect of PA was not identified, PA could influence the initial status of obesity. Because obesity in early years could steadily influence future obesity status, early detection and intervention for adolescent obesity are necessary. Moreover, more studies examining the effect of PA during PE on obesity status among adolescents should be conducted to identify the association between PA during PE and obesity status over time.

Weight, Weight Perceptions, and Health and Well-Being Among Canadian Adolescents: Evidence From the 2017-2018 Canadian Community Health Survey.

Purpose:The present study examines the extent to which (mis)matched weight and weight perceptions predict adolescents’ self-rated health, mental health, and life satisfaction.Design:Quantitative, cross-sectional study.Setting:Data from the 2017-2018 Canadian Community Health Survey (CCHS)—a nationally representative sample collected by Statistics Canada.Participants:Canadian adolescents aged between 12 and 17 (n = 8,081).Measures:The dependent variables are self-rated health, mental health, and life satisfaction. The independent variable is (mis)matched weight and weight perceptions.Analysis:We perform a series of ordinary least squares (OLS) regression models.Results:Overweight adolescents with overweight perceptions are associated with poorer self-rated health (b = −.546, p < .001 for boys; b = −.476, p < .001 for girls), mental health (b = −.278, p < .001 for boys; b = −.433, p < .001 for girls), and life satisfaction (b = −.544, p < .001 for boys; b = −.617, p < .001 for girls) compared to their counterparts with normal weight and normal weight perceptions. Similar patterns have also been observed among normal weight adolescents with overweight perceptions (e.g., normal weight adolescents with overweight perceptions are associated with poorer self-rated health (b = −.541, p < .01 for boys; b = −.447, p < .001 for girls)).Conclusion:Normal weight adolescents are not immune to adverse self-rated health, mental health, and life satisfaction because their weight perceptions are also a contributing factor to health and well-being consequences.

Five years of cardio-ankle vascular index (CAVI) and CAVI0: how close are we to a pressure-independent index of arterial stiffness?

Pulse wave velocity, a common metric of arterial stiffness, is an established predictor for cardiovascular events and mortality. However, its intrinsic pressure-dependency complicates the discrimination of acute and chronic impacts of increased blood pressure on arterial stiffness. Cardio-ankle vascular index (CAVI) represented a significant step towards the development of a pressure-independent arterial stiffness metric. However, some potential limitations of CAVI might render this arterial stiffness metric less pressure-independent than originally thought. For this reason, we later introduced CAVI0. Nevertheless, advantages of one approach over the other are left debated. This review aims to shed light on the pressure (in)dependency of both CAVI and CAVI0. By critically reviewing results from studies reporting both CAVI and CAVI0 and using simple analytical methods, we show that CAVI0 may enhance the pressure-independent assessment of arterial stiffness, especially in the presence of large inter-individual differences in blood pressure.

Weight and Health-related Quality of Life in Children and Adolescents: A Systematic Review

Objective: This systematic review aims to examine the spectrum of research studies including cross-cultural and international studies that have focused on weight and health-related quality of life in children and adolescents. Methods: Following the PRISMA guidelines, studies published in the past 25 years from 1995 until 2020 that pertain to weight and health-related quality of life (HRQoL) in children and adolescents were identified through the use of Pubmed, ScienceDirect, Google Scholar, and PsycInfo databases. Two authors independently conducted a focused analysis and reached a final consensus on which studies to include using specific selection criteria followed by a quality check of the studies, resulting in the final selection of 25 studies. Results: The selected studies particularized the level of impaired quality of life among normal-weight, overweight and obese children and adolescents, and distinctly found that higher participant weight was correlated with a lower HRQoL score. Conclusion: Studies showed a significant negative correlation between weight and HRQoL. Multiple types of prevention and treatment programs are critically needed to provide resources to improve quality of life in overweight and obese children and adolescents.

Estimation of percentage of body fat in field studies – a method based on relative elbow breadth (Frame Index) and BMI

Background&#x0D; Over the last 20 years, a decreasing trend in external skeletal robusticity and an increasing trend in overweight and obesity was observed worldwide in adults and children as modern lifestyles in nutritional and activity behavior have changed. However, body mass index (BMI) as a measure for overweight is not an ideal predictor of % body fat (%BF) either in children and adolescents or in adults. On the contrary, it disguises a phenomenon called “hidden obesity”.&#x0D; Objectives&#x0D; We aim to approximate %BF by combining skeletal robusticity and BMI and develop an estimation-based tool to identify normal weight obese children and adolescents.&#x0D; Sample and Methods&#x0D; We analyzed cross-sectional data on height, weight, elbow breadth, and skinfold thickness (triceps and subscapular) of German children aged 6 to 18 years (N=15,034). We used modified Hattori charts and multiple linear regression to develop a tool, the “%BF estimator”, to estimate %BF by using BMI and skeletal robusticity measured as Frame Index.&#x0D; Results&#x0D; Independent of sex and age an increase in BMI is associated with an increase in %BF, an increase in Frame Index is associated with a decrease in %BF. The developed tool “%BF estimator” allows the estimation of %BF per sex and age group after calculation of BMI and Frame Index.&#x0D; Conclusion&#x0D; The “%BF estimator” is an easily applicable tool for the estimation of %BF in respect of body composition for clinical practice, screening, and public health research. It is non-invasive and has high accuracy. Further, it allows the identification of normal weight obese children and adolescents.

Physical Activity and Body-Mass-Index: Do Family, Friends and Teachers Restrain the Risk for Physical Inactivity in Adolescents?

Background: The present study investigates the role of different sources of social support in the relationship of BMI and PA in an international sample of children and adolescents. Methods: Data included 170,211 adolescents (51.5% female), aged 10–16 (M = 13.6, SD = 1.64) from 37 European countries/regions and were retrieved from the 2013/14 Health Behaviour in School-aged Children (HBSC) international database. Results: PA levels in adolescents are lower for girls, decrease with age, and are lower for overweight and obese adolescents compared to underweight and normal-weight adolescents. Peer support and teacher support significantly predict PA (ORpeer = 1.11; ORteacher = 0.97) and vigorous PA frequency (ORpeer = 1.13; ORteacher = 0.94). Family support only affected vigorous PA frequency (OR = 1.03). Family support had a moderating effect on PA in overweight (ORfamily*BMI(overweight) = 0.94) and obese (ORfamily*BMI(obese) = 0.90) adolescents. Peer support had a moderating effect on vigorous PA frequency in obese (ORpeer*BMI(obese) = 1.08) adolescents. Teacher support had a moderating effect on PA (ORteacher*BMI(normal) = 1.05; ORteacher*BMI(overweight) = 1.09) and vigorous PA frequency (ORteacher*BMI(normal) = 1.07; ORteacher*BMI(overweight) = 1.08) in normal-weight and overweight adolescents. Conclusion: Social support helps adolescents to be active. Especially for obese adolescents, support by and relations with peers are important to reach a significant amount of PA.