Overweight and aerobic fitness in children in the United States/Mexico border region.

OBJECTIVE: To study overweight and aerobic fitness among children in the third and fourth grades of elementary schools in a city in the United States of America (El Paso, Texas) and a city in Mexico (Chihuahua, Chihuahua) that are on or near the border between those two countries, and to compare the results from those two cities with earlier findings for other children in the United States. METHODS: We followed the El Paso children (427 boys and 385 girls, 93% of them of Mexican descent) from third to fourth grade and assessed the change in their body mass index (BMI). In the city of Chihuahua we cross-sectionally measured the BMI of a sample of third grade children (221 boys and 237 girls) and a sample of fourth grade children (268 boys and 215 girls). BMI and triceps skinfolds were measured for all the children studied in the two cities. BMI was used to assess risk for overweight (at least the 85th percentile BMI for age and gender) and overweight (at least the 95th percentile BMI for age and gender) in all the children. The distance that El Paso children ran in nine minutes was used to assess their aerobic fitness (aerobic fitness was not measured in the Chihuahua children). The data from El Paso were collected in 1999, 2000, and 2001, and the Chihuahua data were collected in 2000 and 2001. RESULTS: In the El Paso boys, overweight significantly increased in the one year from third grade to fourth grade, from 22% to 28%, while risk for overweight significantly increased, from 37% to 44%. In the El Paso girls, risk for overweight significantly increased over the same one-year period, from 29% to 37%. The El Paso boys and girls were significantly less fit when compared to samples of children from throughout the United States. Third and fourth grade children from Chihuahua had similar rates of risk for overweight and of overweight when compared to the children from the same grades in El Paso. CONCLUSIONS: Children in both El Paso and Chihuahua were more overweight than were non-Hispanic white children throughout the United States. In addition, the children in El Paso were less aerobically fit than were non-Hispanic white children and than were other Mexican-American children in the United States. These results clearly show that efforts should be made in the border regions of both Mexico and the United States to develop physical activity and nutrition programs to help stem rising rates of overweight.     

Prevalence of marked overweight and obesity in a multiethnic pediatric population: findings from the Child and Adolescent Trial for Cardiovascular Health (CATCH) study

OBJECTIVE: Determine the prevalence of marked overweight and obesity among children in the Child and Adolescent Trial for Cardiovascular Health (CATCH), identify high risk groups, and compare findings to other recent studies. DESIGN: Cohort study. SUBJECTS/SETTING: Five thousand one hundred-six school children who were participants in CATCH at baseline (age approximately 9 years) during 1991 and 4,019 of those children who had follow-up data from 1994 (age approximately 1 years) available. METHODS: Body mass index (BMI), triceps and subscapular skinfolds, subscapular to triceps skinfold (S/T) ratio, and an estimate of body fat distribution from skinfolds was calculated. Findings were compared to population-based reference data from the First National Health and Nutrition Examination Survey, 1971 to 1973 (NHANES I), to data from the Bogalusa Heart Study, and to data from the Third National Health and Nutrition Examination Survey, 1988 to 1994 (NHANES III). RESULTS: Children in CATCH were markedly heavier and fatter than the NHANES I population and more comparable to the NHANES III population, especially those in the upper percentiles. The prevalence of obesity based on BMI and triceps skinfolds >95th percentile among CATCH children was higher in boys than in girls at both baseline (boys 9.1%, girls 8.6%) and follow-up (boys 11.7%, girls 7.2%). It was higher among African-Americans and Hispanics than whites for both sexes. S/T ratios did not differ appreciably from those observed in the NHANES I reference population, suggesting that body fat distribution was more stable over time than BMI and skinfolds. APPLICATIONS: Our findings support other recent reports that American children, especially African-American and Hispanic children, are becoming heavier and fatter. Preventive measures are warranted, especially for high-risk youth.     

Prevalence of overweight in north Florida elementary and middle school children: effects of age, sex, ethnicity, and socioeconomic status

BACKGROUND: The number of overweight children has been rapidly increasing, although its prevalence varies by age, sex, ethnicity, and socioeconomic (SES) status. METHODS: Height and weight assessments were used to calculate body mass index (BMI) and BMI percentile on more than 17,000 children in 1 north Florida school district's elementary and middle schools. Based on the child's BMI percentile, each child was placed into 1 of 4 groups: underweight, normal, at risk for overweight, and overweight. Logistic regression was used to test the relative contribution of sex, ethnicity, school (elementary vs middle), age, and SES (indicated by free/reduced vs full-pay lunch status) to a child's weight classification. RESULTS: Overall, 36.2% of the children were either overweight (18.9%) or at risk for overweight (17.4%). Approximately 30% of the kindergarten children were overweight (14.0%) or at risk for overweight (15.5%). African American children were most likely to begin kindergarten overweight. The prevalence of overweight increased for all ethnic groups during the elementary school years. However, African American girls and Hispanic boys were more likely to be overweight than any other ethnic group; Asian girls were least likely to be overweight. These findings could not be readily explained by the effects of SES. Higher SES appeared to be protective but only for white and Hispanic children. CONCLUSIONS: These results confirm the increasing prevalence of overweight in US school children, especially among African American girls and Hispanic boys.     

Obesity among pre-adolescent and adolescents of a developing country (India)

There are very few reports from the developing world on the prevalence of obesity among children even though in developed countries it has reached epidemic proportions. The objective of this study was to determine the prevalence of obesity in pre-adolescent and adolescent children in a developing country (India) using WHO guidelines for defining obesity and overweight. This cross-sectional study was carried out on 2008 school-children aged 9-15 years. Approximately half the subjects belonged to a school attended by children of well to do families while the rest belonged to two schools from middle and lower socio-economic background. Weight and height were taken for all children and the body mass index (BMI) calculated. Children whose BMI was >85th percentile for age and sex were defined as overweight. Triceps skin fold thickness (TSFT) was measured for all overweight children and those with TSFT >90th percentile for age and sex were defined as obese. The overall prevalence of obesity and overweight was 11.1% and 14.2% respectively. The prevalence of obesity as well as overweight was higher in boys as compared to girls (12.4% vs 9.9%, 15.7% vs 12.9%). Prevalence of obesity decreased significantly with age, from 18.5% at 9 years to 7.6% at 14 years, rising at 15 years to 12.1%. Significantly more children from higher socio-economic status were obese and overweight than those from lower socio-economic status groups. No significant gender difference for obesity prevalence was seen among children from a less privileged background, however, amongst children from affluent families, significantly more boys were obese as compared to girls. Pediatric obesity is an emerging problem in developing countries, especially among higher socio-economic status groups. Significant gender disparity is seen, with boys of affluent background having a higher prevalence.     

Obesity rates among rural Ontario schoolchildren

BACKGROUND: The majority of existing studies of obesity risk among Canadian children come from urban populations. The purpose of this study is to assess the prevalence of obesity in a sample of rural Ontario children. METHODS: Measures of height and weight were obtained for 504 children attending seven public elementary schools in Grey and Bruce Counties, a predominantly rural area of Southern Ontario. Body mass index (BMI, or weight/height2) scores were calculated and compared with reference data from the Centers for Disease Control. RESULTS: Rates of overweight and obesity were high in this sample, with 17.7% of children classified as overweight and 10.9% classified as obese. There was a significantly high prevalence of overweight for both boys (17.8%) and girls (17.5%) (Chi-square = 75.70, p < 0.001). However there was a significant gender difference in obesity prevalence: 15.0% of boys were obese, compared with 6.8% of girls (Mann-Whitney U = 29133.0, p > 0.05). CONCLUSION: Findings indicate that among rural children--particularly boys--risk of overweight and obesity are at least as high as in their urban Canadian counterparts. There appear to be fewer girls than boys at the extreme high end of the distribution of BMI, which may indicate differences in the growth environment of rural boys and girls.     

Die Verbreitung von Übergewicht und Adipositas bei Kindern und Jugendlichen in Deutschland

Overweight and obesity are an increasing problem: worldwide, for Germany and for children and adolescents. Until now there have been no representative and age-specific assessments of the prevalence of obesity among children and adolescents in Germany. Thus, the standardised height and weight measurements gathered in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) have, for the first time, provided national, representative data about overweight and obesity in young people. The terms 'overweight' and 'obese' are defined based on percentiles of the body mass index (BMI) of the Kromeyer-Hauschild reference system. Of children and adolescents between the ages of 3 and 17, 15% exceed the 90th BMI percentile of the reference data and are thus overweight, 6.3% exceed the 97th BMI percentile and thus suffer from obesity by this definition. The proportion of overweight rises from 9% of 3-6-year-olds to 15% of 7-10-year-olds and 17% of 14-17-year-olds. The prevalence of obesity is 2.9%, 6.4% and 8.5% for the same age groups respectively. No clear differences between boys and girls or between East and West Germany are detected. Children are at a higher risk of being overweight or obese if they have a lower socioeconomic status, have a migration background, or have mothers who are also overweight.     

Central adiposity in Brazilian schoolchildren aged 7-10 years

Waist circumference (WC) is a measure of central adiposity related to elevated risk factor levels in children and adolescents. The aim of the present study was to describe WC percentiles in 7- to 10-year-old Brazilian children and to compare frequencies of obesity and overweight as defined by BMI and frequencies of excess and at risk of abdominal adiposity as defined by WC to the corresponding age and sex data from British references. A representative sample of 2919 schoolchildren of the city of Florianopolis (southern Brazil) was examined. Smoothed WC percentiles were derived using the least mean square method. Frequencies of overweight and obesity and of excess and at risk of abdominal adiposity were assessed using the 91st and 98th centiles of the British references as cut-off points. WC increased with age in both boys and girls, with higher values for boys at every age and percentile level. Nutritional status categories of children assessed by the 91st and 98th British BMI and WC centiles showed moderate agreement (weighted kappa = 0.58). Overweight was more frequent in Brazilian than British children: 15.1 % of girls and 20.1 % of boys were above the 91st percentile of the 1990 BMI for age British references. About one-quarter (22.0 % of girls and 26.9 % of boys) exceeded the 91st percentile of WC British references. The present data could be used to compare WC in children in other populations and may serve as a baseline for future studies of temporal trends in WC in Brazil.     

Trajectories of Overweight Among US School Children: A Focus on Social and Economic Characteristics

Much of the research examining the patterns, timing, and socioeconomic characteristics of child overweight has been limited by the lack of longitudinal nationally representative data with sufficiently large or diverse samples. We used the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K), a nationally representative sample of US kindergartners, to identify three distinct patterns of weight gain from kindergarten through eighth grade. The largest group (boys: 59%, girls: 55%) was characterized as having consistently normal weight whereby BMI percentile remained below the 85th percentile. The remaining children (boys: 41%, girls: 45%) fell either into a class characterized as always overweight/at risk of overweight (boys: 27%, girls: 25%) or gradually becoming overweight/at risk for overweight (boys: 15%, girls 20%). We found some evidence that the relationship between socioeconomic status and children’s health may operate differently across gender. Among girls, low parental income and education were both significant risk factors for the gradual onset of overweight after beginning Kindergarten. Parental income or changes in parental income were not related to boys’ risk of developing overweight after entering Kindergarten; only parents’ education. We found that while children of immigrants display higher levels of overweight/at risk for overweight at each grade level, the children of immigrant parents who have had less exposure to the US were more likely to experience early and sustained overweight throughout elementary and middle school, particularly among boys. High rates of overweight as early as kindergarten, combined with race/ethnic differences suggest that interventions should focus on pre-school children’s environments.     

Prevalence of overweight and obesity among Costa Rican elementary school children.

OBJECTIVE: Given that excessive body weight during childhood influences the development of several chronic diseases in adulthood, this study was conducted to determine the prevalence of overweight and obesity in urban and rural Costa Rican elementary school children. METHODS: The study was carried out from July 2000 to April 2001. A total of 1 718 students ages 7-12 were selected from 34 schools in the capital city of San José and in other nearby urban and rural areas. Both younger children (ones aged 7 through 9 years) and older children (ones aged 10 through 12 years) with a body mass index (BMI) at or above the sex-specific 85th percentile were considered overweight. The younger children were classified as being obese if their triceps skinfold was greater than or equal to the 85th percentile for age and sex using the percentiles by age for children in the United States of America as normative standards. The older children were considered obese if they had a BMI at or above the sex-specific 85th percentile and both the triceps and subscapular skinfold thickness at or above the 90th percentile. RESULTS: The prevalence of overweight was 34.5%. Children aged 7-9, boys, children from urban areas, and children of a higher socioeconomic status had a higher prevalence of overweight. The prevalence of obesity was 26.2%. A higher prevalence of obesity was found among children aged 7-9, boys, children from urban areas, and children of middle socioeconomic status. CONCLUSIONS: Given the high prevalence of obesity that we found in the Costa Rican children, primary and secondary prevention measures are needed in order to reduce the proportion of deaths due to chronic nontransmissible diseases among Costa Rican adults in the coming decades.     

The high prevalence of overweight and obesity in Mexican children

OBJECTIVE: To establish the prevalence of overweight and obesity in Mexican children 10 to 17 years of age according to the percentiles from both the Centers of Disease Control and Prevention (CDC) and the International Obesity Task Force (IOTF). RESEARCH METHODS AND PROCEDURES: Heights and weights were measured in children from nationally representative, randomly chosen households in the Mexican National Health Survey 2000. The study population consisted of 7862 boys and 8947 girls, 10 to 17 years of age. Measurements used were the percentage of children in the corresponding BMI categories for overweight and obesity specified by the CDC and the IOTF BMI percentiles. RESULTS: The children were short, with mean Z scores for height by age varying from - 0.62 +/- 1.26 to -1.12 +/- 1.06 in boys and from -0.45 +/- 1.25 to -1.19 +/- 1.12 in girls. CDC-based overweight prevalences varied by age from 10.8% to 16.1% in boys and 14.3% to 19.1% in girls, with obesity prevalences from 9.2% to 14.7% in boys and 6.8% to 10.6% in girls; these prevalences did not relate to stunting. IOTF-based excess weight prevalences were similar, with higher overweight rates (boys, 15.4% to 18.8%; girls, 18.4% to 22.3%) but lower obesity rates (boys, 6.1% to 9%; girls, 5.9% to 8.2%). DISCUSSION: Mexican children have one-half the overweight/obesity prevalences of U.S. Mexican-American children; however, there are higher rates in Northern Mexico, which is closer to the U.S. These escalating rates of excess weight demand new prevention, as well as management, policies.     

Obesity in a cohort of black Jamaican children as estimated by BMI and other indices of adiposity

OBJECTIVE: To examine the relationships of body mass index (BMI) to obesity indices derived from anthropometry and to determine tracking of overweight between late childhood and early adolescence, in a cohort of children with mixed nutritional history. We also compared identification of overweight children using The International Obesity Task Force (IOTF) BMI cut-off points with skinfolds. DESIGN: Prospective study. SETTING: Kingston, Jamaica. SUBJECTS: A total of 306 children examined at 7-8 y and at 11-12 y. MEASUREMENTS: Triceps (TSF) and subscapular skinfolds (SSF), height and weight were measured. The sum of the skinfolds (sum SF), BMI, percentage body fat (%fat) and fat mass (FM) were calculated. Pubertal stage was assessed at 11-12 y. RESULTS: Overweight increased from 3.5 to 9.5% over the follow-up period. BMI was better correlated with the other indices of adiposity in girls and in the older age group. BMI tracking over follow up was high. In regression analysis BMI explained 52 and 61% of the variance in FM in boys and girls at 7-8 y. This increased to 69% in both sexes at 11-12 y. Using the IOTF cut-off points BMI had low sensitivity to identify children >85th percentile of the NHANES references for SSF. The sensitivity for those assessed by TSF and sum SF was higher, but between 14 and 30% of the children were misclassified. The specificity of BMI was high. CONCLUSIONS: Adiposity increased over follow-up. Although the cohort remained relatively lean BMI rank among the fattest children was maintained. Girls were fatter than boys, reflecting adult obesity patterns. Children identified as overweight by the IOTF BMI cut-off points are likely to have high body fatness. However the BMI cut-off points may not identify many children with high body fatness.     

Racial differences in the tracking of childhood BMI to adulthood

OBJECTIVE: The possibility that there are racial differences in the patterns of BMI (kilograms per meter squared) change throughout life has not been examined. For example, the high prevalence of obesity among black women could result from a higher prevalence of obesity among black girls or because normal-weight black girls experience larger BMI increases in adolescence or adulthood than do their white counterparts. Therefore, we examined the tracking of childhood BMI into adulthood in a biracial (36% black) sample. RESEARCH METHODS AND PROCEDURES: Five- to 14-year-old children (2392) were followed for (mean) 17 years. Childhood overweight was defined as BMI > or = 95th percentile, and adult obesity was defined as BMI > or = 30 kg/m(2). RESULTS: The tracking of childhood BMI differed between whites and blacks. Among overweight children, 65% of white girls vs. 84% of black girls became obese adults, and predictive values among boys were 71% (whites) vs. 82% (blacks). These racial differences reflected contrasting patterns in the rate of BMI change. Although the initial BMI of black children was not higher than that of white children, BMI increases with age were larger among black girls and overweight black boys than among their white counterparts. In contrast, relatively thin (BMI < 50th percentile) white boys were more likely to become overweight adults than were their black counterparts. DISCUSSION: These findings emphasize the black/white differences in BMI changes with age. Because of the adult health consequences of childhood-onset obesity, early prevention should be given additional emphasis.     

Mexican anthropometric percentiles for ages 10-18

OBJECTIVE: To elaborate Mexican growth charts based on international methodology. DESIGN: Data were obtained from the Mexican National Health Survey. The survey was stratified and probabilistic representative of all the country. SETTING: Nationwide open population living in urban and rural areas. SUBJECTS: Boys (8545) and girls (9983) from 10 to 18 years participating in the survey. METHODS: Age, weight and height were recorded. Empirical percentiles were calculated and smoothed. Smoothed curves were approximated using least-mean square estimation. RESULTS: Tables and figures for percentile values of weight, height and body mass index (BMI) for age, as well as percentile values of weight and BMI for height for both genders are presented. Regarding 50th BMI for age percentiles, Mexicans had higher levels than the Americans in the Centers for Disease Control and Prevention growth charts; Mexicans were lower but had similar weights than the Americans. Owing to the high BMI, the percentile corresponding to an overweight level (25 kg/m(2)) at 18 years was 74.5 in boys and 72.5 in girls, whereas obesity level (30 kg/m(2)) at 18 years was 97.3 and 97.4 in boys and girls, respectively. CONCLUSIONS: The present growth charts are snapshots of a Mexican population. Because of the high median BMI compared to US and World Health Organization standards, we must be cautious in establishing an upper normal cutoff for clinical normality, not merely selecting the 85th and 95th percentiles as equivalents of overweight and obesity, respectively. Therefore, we proposed percentiles 74.5 in boys and 72.5 in girls as the action points of overweight as they are the percentiles corresponding to BMI 25 kg/m(2) at 18 years. SPONSORSHIP: The survey was supported by the Mexican Minister of Health. Statistical analyses were sponsored by Dr Del-Rio-Navarro.     

Impact of objective and subjective social status on obesity in a biracial cohort of adolescents

OBJECTIVE: To characterize the associations between socioeconomic status (SES), two levels of subjective social status (SSS), and adolescent obesity. RESEARCH METHODS AND PROCEDURES: Cross-sectional study of 1491 black and white adolescents attending public school in a suburban school district in Greater Cincinnati, Ohio. BMI > or =95th percentile derived from measured height and weight defined overweight. Students rated SSS on separate 10-point scales for society and school. A parent provided information on parent education and household income for SES. RESULTS: Although there were no sex differences in SES, black students were more likely to come from families with less well-educated parents and lower incomes (p < 0.001). Black girls had the lowest societal SSS (p = 0.003), lowest school SSS (p = 0.046), and highest BMI (p < 0.001). Prevalence of overweight was highest among black girls (26.0%) and boys (26.2%), intermediate for white boys (17.2%), and least for white girls (11.6%). Logistic regression modeling revealed that parent education, household income, and school SSS were each associated with overweight. In a fully adjusted model, school SSS retained its association to overweight (odds ratio, 1.16; 95% CI, 1.06,1.26) independent of SES. The association of school SSS was strongest among white girls, intermediate for white and black boys, and absent for black girls. DISCUSSION: Perceptions of social stratification are independently associated with overweight. There were important racial and sex differences in the social status-overweight association. SSS in the more immediate, local reference group, the school, had the strongest association to overweight.     

Childhood Asthma and Extreme Values of Body Mass Index: The Harlem Children’s Zone Asthma Initiative

To examine the association between body mass index (BMI) percentile and asthma in children 2-11 years of age, we performed a cross-sectional analysis of 853 Black and Hispanic children from a community-based sample of 2- to 11-year olds with measured heights and weights screened for asthma by the Harlem Children's Zone Asthma Initiative. Current asthma was defined as parent/guardian-reported diagnosis of asthma and asthma-related symptoms or emergency care in the previous 12 months. Among girls, asthma prevalence increased approximately linearly with increasing body mass index (BMI) percentile, from a low of 12.0% among underweight girls (BMI 95th percentile). After adjusting for age, race/ethnicity, and household smoking, among girls, having asthma was associated with being at risk for overweight (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.4-5.0) and being overweight (OR, 2.1; 95% CI, 1.2-3.8) compared to normal weight; among boys, having asthma was associated both with overweight (OR, 2.4; 95% CI, 1.4-4.3) and with underweight (OR, 2.9; 95% CI, 1.1-7.7). Large, prospective studies that include very young children are needed to further explore the observed association between underweight and asthma among boys. Early interventions that concomitantly address asthma and weight gain are needed among pre-school and school-aged children.     

Overweight, stunting, and anemia are public health problems among low socioeconomic groups in school adolescents (12-15 years) in the North Gaza Strip

The objective of the study was to describe sociodemographic differences in nutritional status among school adolescents aged 12 to 15 years in north Gaza Strip. A cross-sectional survey was conducted in 2002 comprising 1022 students from 10 schools in Gaza city, Jabalia village, and Jabalia refugee camp. Height, weight, and hemoglobin levels were measured to assess nutritional status. Self-administered questionnaires were administered to students and parents to obtain data on sociodemographic characteristics. The prevalence of overweight/obesity, stunting, and anemia in the total sample was 17.9%, 9.7%, and 49.6%, respectively. More overweight/obese girls than boys were found (20.2% vs 15.4%). In girls, being from a low-income residential area, having employed fathers, and having reached puberty had highest risk of overweight/obesity, whereas in boys, those with medium socioeconomic status (SES) had the lowest risk of overweight. The mean height-for-age percentile was generally low for both sexes compared with the National Center for Health Statistics/World Health Organization reference, but stunting was more common in boys than girls (13.7% vs 6.2%). Age was positively associated with risk of stunting in boys, whereas in girls, SES and mother's education were negatively associated with stunting. Anemia prevalence was high in both girls and boys (51.3% vs 47.9%). Age and onset of puberty had an independent negative effect on anemia among boys. Girls from nuclear families and from Jabalia village had higher risk of being anemic. In conclusion, undernutrition and overnutrition coexisted in the study area. Anemia, stunting, and overweight among the adolescents are public health problems, especially among low SES groups that merit attention.     

Nutritional status of first to fourth-grade students of urban schools in Pelotas, Rio Grande do Sul State, Brazil

This cross-sectional study included 20,084 students from urban schools (first to fourth-grade) in Pelotas, Rio Grande do Sul State, Brazil. Weight and height were measured, and nutritional status was classified according to the World Health Organization (height deficit) and International Obesity Task Force (overweight and obesity) criteria. The study also recorded the variables age, gender, type of school, and schooling (grade-for-age adequacy). Prevalence of height-for-age deficit was 3.5% (3.9% in boys and 3.1% in girls). Prevalence rates for overweight and obesity were 29.8% and 9.1%, respectively. Overweight and obesity were more frequent in private schools, while height-for-age deficit was more frequent in municipal or State schools. For both boys and girls, age was positively associated with underweight and inversely related to overweight and obesity. Inadequate schooling was associated with increased risk of height deficit and decreased risk of overweight and obesity. In conclusion, primary students' nutritional status depends not only on demographic and socioeconomic factors, but also on type of school.     

Percent body fat cutoff values for classifying overweight and obesity recommended by the International Obesity Task Force (IOTF) in Korean children

OBJECTIVE: To predict the percent body fat (%BF) cutoff values corresponding to overweight and obesity recommended by the International Obesity Task Force (IOTF) in Korean children and to compare those values with the published cutoff values in Caucasian children. RESEARCH METHODS AND PROCEDURES: The sample consisted of 1083 Korean children and adolescents (555 boys and 528 girls) aged 7-18 years from 3 schools. Body mass index (BMI) and %BF using a bioelectrical impedance analyzer were measured. The classification of overweight and obesity was based on the age- and sex-specific BMI cutoff values of the IOTF guidelines. RESULTS: The predicted %BF cutoff values for overweight and obesity varied by age and sex: overweight, 17-22% in boys and 24-37% in girls; obesity, 24-30% in boys and 30-53% in girls. Those %BF cutoff values in older Korean boys tended to be lower than the published %BF cutoff values in Caucasian boys. While %BF cutoff values for overweight in Korean girls were similar to the values in Caucasian girls, %BF cutoff values for obesity in Korean girls aged 13-18 years were higher compared to cutoff values in Caucasian girls. CONCLUSION: The %BF values associated with the IOTF-recommended BMI cutoff values for overweight and obesity may require age- and sex-specific cutoff values in Korean children aged 7-18 years.     

Associations of behavioural, psychosocial and socioeconomic factors with over- and underweight among German adolescents

OBJECTIVES: The prevalence of overweight and obesity has dramatically increased in western societies. This paper examines behavioural, psychosocial and socioeconomic factors associated with overweight and underweight among adolescents in Germany. METHODS: Data from the German part of the 2001/02 Health Behaviour in School-aged Children (HBSC) survey, composed of 5,650 respondents aged 11 to 17 years were analysed. Body mass index (BMI) was calculated based on self-reported weight and height. The overweight category was defined as BMI within or above the 90th percentile of specific BMI values for gender and age in the German national sample. The underweight category was defined as BMI within or below the 10th percentile of this sample. A multinomial logistic regression model was used to investigate the association between behavioural, psychosocial and socioeconomic factors and BMI categories. RESULTS: 9.5 % of the boys and 5.4 % of the girls were classified as overweight. The prevalence of underweight was 12.6 % among boys and 19.1 % among girls. Several factors were associated with over- and/or underweight in the bivariate analysis, showing different patterns for gender and BMI categories. In the multivariable model only low family affluence, high sedentary behaviour, and being bullied (for girls only) remained positively associated with being overweight. Being underweight was negatively associated with higher age and low parental occupation; it differed also by region. CONCLUSION: Despite several variables being associated with overweight and underweight in bivariate models, only three factors remained associated with overweight in multivariable analysis. Other considered variables did not have independent associations with the outcome, but still could be included in respective causal pathways. Our results suggest that preventive strategies focussing on students of low socio-economic status and the avoidance of sedentary behaviours could help to address issues of overweight and obesity.