Relationship between BMI and blood pressure in girls and boys

AimTo investigate the relationship between BMI and blood pressure as this is of crucial interest in evaluating both public health and the clinical impact of the so-called obesity epidemic. METHODS: Data were gathered from 1899 children aged between 6 and 14 years, analysing and evaluating a possible relationship between BMI and systolic and diastolic blood pressure values for both girls and boys. Each child was classified on the basis of age- and sex-specific BMI percentile as normal weight (<85th percentile), overweight (95th percentile). RESULTS: In comparisons among ageBMI percentile groups, systolic and diastolic blood pressure values were higher in obese and overweight groups than in normal weight groups for both sexes. Although BMI among girls was higher than among boys in all three percentile groups, there were no significant differences between sexes with respect to blood pressure values.ConclusionThe present findings emphasize the importance of the prevention of obesity in order to prevent future related problems such as hypertension in children and adolescents.     

Ethnic differences in body mass index and associated factors of adolescents from minorities in Oslo, Norway: a cross-sectional study

OBJECTIVES: To examine ethnic differences in body mass index (BMI), food habits and physical activity, and determine the factors contributing to differences in BMI. DESIGN AND METHOD: In 2000-2001, 7343 (response rate 88%) 15- and 16-year-old students, enrolled in lower secondary schools in Oslo, participated in the cross-sectional Oslo Health Study. Of these participants, 1719 were defined as ethnic minorities. RESULTS: Significant gender and ethnic differences in mean BMI were observed. Of the ethnic minority adolescents, 5.8% were underweight (<5th percentile of the US Centers for Disease Control and Prevention (CDC)/National Center for Health Statistics (NCHS) reference distribution) and 9.1% were overweight (>85th percentile of the US CDC/NCHS reference distribution). BMI was not significantly associated with either socio-economic factors or physical activity. Food habits and physical activity differed with ethnicity but not with socio-economic factors. An ordinal regression showed that girls from East Asia (odds ratio (OR) 0.4) and boys from sub-Saharan Africa (OR 0.4) had lower BMI than the Western group. Among girls, higher BMI was associated with less frequent consumption of chocolates and sweets, full-fat milk and breakfast (OR 2.4, 1.7 and 1.7, respectively). Higher BMI, for both boys and girls, was associated with current and past dieting (OR 3.7 and 4.2, respectively). CONCLUSIONS: Adolescent food habits and physical activity varied by gender and ethnicity but not with socio-economic factors. BMI was associated with ethnicity, gender and food habits, but no significant relationship was observed with socio-economic factors or physical activity. Ethnicity, in addition to gender, should be taken into consideration when studying BMI and associated factors among adolescents.     

Nutritional status of the Andean population of Puna and Quebrada of Humahuaca, Jujuy, Argentina

OBJECTIVE: To assess the nutritional status of the Andean population of Puna and Quebrada of Humahuaca, Jujuy, using anthropometric measurements. DESIGN AND SUBJECTS: A cross-sectional nutritional survey was carried out in a representative sample (n = 1236) of individuals from these regions. Children aged 2-9 years, adolescents (10-17 years) and adults (>or=18 years; pregnant and lactating women excluded) were considered. Height-for-age, weight-for-height and body mass index (BMI) were calculated in children and adolescents and compared with World Health Organization/National Center for Health Statistics/Centers for Disease Control and Prevention reference standards using Z-scores or percentiles, in order to assess the prevalence of stunting, wasting/thinness and excess weight. In adults, BMI, waist circumference (WC) and waist-to-hip (WHR) ratio were used to identify obesity and central adiposity. RESULTS: Stunting (height-for-age Z-score <-2 standard deviations) and obesity (BMI >or= 95th percentile) were found to be major nutritional problems in children and adolescents. Stunting was prevalent in 10.7% of children and 12.4% of adolescents; 8.2% of children and 3.5% of adolescents were obese. Adults were short (mean: 155.8 cm) and values of overweight (32.3%), obesity (18.3%) and central adiposity (mean WC: 86.5 cm) were high. Older adults and those with higher economic development showed higher prevalence of obesity and central adiposity. CONCLUSIONS: The present population may be at the early stages of nutritional transition as symptoms of undernutrition and overnutrition coexist at the population level. These results suggest that rates of growth retardation may be decreasing owing to improved nutritional conditions; however, this could be accompanied by a sharp increase in the prevalence of other diet-related chronic diseases.     

Body mass index, physical activity and dietary behaviours among adolescents in the Kingdom of Tonga

OBJECTIVES: To compare the prevalence of overweight and obesity among adolescents using international and ethnic-specific cut-off points and to examine patterns of physical activity and dietary behaviours. DESIGN: Cross-sectional analytical study. SETTING: Schools on Tongatapu, Vava'u and Hapa'ai islands in the Kingdom of Tonga. SUBJECTS: A total of 443 school students aged 11-16 years underwent anthropometric measures of height and weight and provided self-reported measures of physical activity and dietary behaviours.Results Mean body mass index (BMI) was higher among girls than boys (23.7 kg m(-2) vs. 21.8 kg m(-2) and tended to increase with age. A total of 36.0% of boys and 53.8% of girls were overweight or obese using the international cut-off points, whereas 25.0% of boys and 37.6% of girls were classified in this way using Polynesian-specific cut-off points. Tinned mutton or beef was the food that most participants (56.9%) reported eating once or more per day. Over half of the young people did not eat taro, fruit or vegetables at least once per day. Regular physical activity outside of school hours was reported by 20.7% of respondents, and 58.2% watched 1 h or more of television per day. Physical activity participation was the only behaviour independently associated with a lower risk of overweight or obesity.Conclusions Using Polynesian-specific cut-off points for overweight and obesity the prevalence of these conditions was still among the highest found in adolescents. The prevalence of physical inactivity and poor dietary habits indicate that risk factors for chronic disease are well established during adolescence in Tonga.     

Diet and overweight and obesity in populations of African origin: Cameroon, Jamaica and the UK

OBJECTIVES: To determine the relationship of diet to overweight and obesity among populations of African origin. DESIGN AND SETTING: Cross-sectional data were obtained from adults aged 25-74 years in rural Cameroon (n = 686), urban Cameroon (n = 975), Jamaica (n = 924) and Afro-Caribbeans in the UK (n = 257). Dietary data were collected using food-frequency questionnaires specifically designed for each site. Body mass index (BMI) was used as a measure of overweight. RESULTS: The expected gradient in the distribution of overweight across sites was seen in females (rural Cameroon, 9.5%; urban Cameroon, 47.1%; Jamaica, 63.8%; UK, 71.6%); however, among males overweight was less prevalent in Jamaica (22.0%) than urban Cameroon (36.3%). In developing countries increased risks of overweight (BMI > or = 25 kg m(-2) were influenced by higher energy (urban Cameroonian men) and protein (Jamaican women) intakes. No dietary variables were associated with obesity (BMI > or = 30 kg m(-2) in Cameroon or Jamaica. In the UK, energy intakes were inversely related with overweight whereas increased risks of being overweight were associated with higher protein (men) and fat (women) intakes. Similarly, whereas higher protein and fat intakes in UK men and women were associated with obesity, carbohydrate intakes were associated with decreased risks of obesity in men. CONCLUSIONS: Diet and overweight were associated in the UK but few dietary variables were related to overweight in Jamaica and the Cameroon. These findings suggest that associations between diet and overweight/obesity are not generalisable among populations.     

Anthropometry of women of childbearing age in Morocco: body composition and prevalence of overweight and obesity

OBJECTIVE: To determine the prevalence of obesity and body fat distribution of Moroccan women of childbearing age, using a panel of anthropometric measurements. DESIGN AND SETTING: A cross-sectional survey conducted in 1995 in an agricultural community, El Jadida province of Morocco. Weight, height, waist and hip circumferences and triceps, biceps, subscapular and supra-iliac skinfold thicknesses were measured. Body mass index (BMI), waist/hip ratio (WHR), sum of all and sum of trunk skinfold thicknesses were determined. SUBJECTS: In total, 1269 women aged 15-49 years from urban and rural areas were surveyed. RESULTS: The means of all anthropometric measurements including body fat were higher in urban than in rural women and increased with age. Trunk fat contributed 50% of total fat. Globally, 4.7% of women were underweight (BMI<18.5 kg m(-2)), 35.2% were overweight or obese (BMI> or =25 kg m(-2)), 10.1% were obese (BMI> or =30 kg m(-2)) and 16.8% had central obesity (WHR>0.85). The prevalence of overweight and obesity was higher in the urban than in the rural area. Underweight prevalence decreased with age, whereas that of overweight and obesity increased. All anthropometric parameters adjusted for age increased with the increase of BMI and WHR. CONCLUSIONS: Although undernutrition is still prevalent, there is an alarming prevalence of overweight and obesity in Moroccan women of childbearing age. The results indicate a shift in this country from the problem of dietary deficiency to the problem of dietary excess, and alert one to the necessity of establishing an intervention to prevent obesity-related diseases. It is necessary to address which of the anthropometric variables studied here is the best predictor of obesity-related diseases in this population.     

Prevalence of overweight and obesity among school-aged children in urban, rural and mountain areas of the Veneto Region, Italy

OBJECTIVE: To define the prevalence of overweight and obesity among school-aged children resident in mountain areas, rural areas and urban areas.Design, setting and subjectsThe sample (n = 12 832; 50.7% boys) included 9- and 11-year-old children of the Veneto Region of north-east Italy. Overweight and obesity status were determined using the International Obesity Task Force cut-off points for body mass index. The prevalence of overweight and obese subjects was calculated with a confidence interval of 95%. The Mantel-Haenszel method was used to compare the combined prevalence of overweight and obesity among children resident in mountain areas, rural areas and urban areas. RESULTS: Among boys the prevalence of overweight was 21.06%, while obesity prevalence was 5.92%; among girls overweight prevalence was 21.30%, while obesity prevalence was 5.15%. The prevalence was higher among 11-year-old boys (odds ratio (OR) = 1.19; 95% confidence interval (CI): 1.06-1.33) and 9-year-old girls (OR = 1.13; 95% CI: 1.01-1.26). Children resident in rural areas presented a higher risk of overweight and obesity compared with children resident in mountain areas (Mantel-Haenszel OR = 1.27; 95% CI: 1.13-1.42; chi2 = 17.55; P < 0.0001) and in urban areas (Mantel-Haenszel OR = 1.18; 95% CI: 1.07-1.31; chi2 = 10.39; P < 0.001). CONCLUSIONS: A relevant prevalence of overweight and obesity was found; the excess weight concerns one child in four. There are differences linked to different geographical areas that must be further investigated.     

Past food habit change is related to obesity, lifestyle and socio-economic factors in the Malmo Diet and Cancer Cohort

OBJECTIVES: To examine if obesity status and socio-economic and lifestyle factors are associated with self-reported past food habit change, and also whether the level of obesity depends on the reason for change. DESIGN: Cross-sectional analysis within the Malmo Diet and Cancer (MDC) study using data from the baseline examination and the extensive socio-economic and lifestyle questionnaire including questions of past food habit change. The risk of having changed food habits in the past was examined using logistic regression. Mean differences in obesity status across categories of reasons for past food habit change were examined using analysis of variance. SETTING: Malm?, the third largest city in Sweden. SUBJECTS: A sub-sample (15 282 women and 9867 men) from the MDC cohort recruited from 1992 to 1996. RESULTS: Individuals with body mass index (BMI) >30 kg m(-2) had an increased risk of having reported past food habit change compared with individuals with BMI <25 kg m(-2) (odds ratio (OR) = 1.63, 95% confidence interval (CI) = 1.48-1.83 for women; OR = 1.53, 95% CI = 1.32-1.76 for men). The highest level of obesity was observed among individuals who had changed their diet due to reasons related to the metabolic syndrome. Changers were more likely to be highly educated and to live alone, be retired, ex-smokers and non-drinkers at baseline. CONCLUSIONS: Because past food habit change is related to obesity and other lifestyle and socio-economic factors, a complex confounding situation may exist that could seriously influence observed relationships between diet and disease. Studies need to collect information on past food habit change and take this information into account in the analysis and when interpreting study outcomes.     

Is overweight and obesity in 9-10-year-old children in Liverpool related to deprivation and/or electoral ward when based on school attended?

OBJECTIVES: To determine whether weight problems in children (overweight, obesity and overweight or obesity) were related to deprivation indices when attributed only according to electoral ward of the school attended. To determine whether children with weight problems were more likely to be found in some wards rather than others, and to compare the distribution for boys and girls. DESIGN: Retrospective, cross-sectional, observational study. SETTING: One hundred and six primary schools from all parts of Liverpool city. SUBJECTS: Five cohorts of 9-10-year-old children between 1998 and 2003. Main outcome measures: Body mass index (BMI) for each child to estimate proportions overweight, obese and overweight or obese according to international criteria. RESULTS: Between January 1998 and March 2003, the heights and weights of 7902 boys and 7514 girls were measured and BMI calculated. The prevalence of boys and girls categorised as overweight or obese was very high (1620, 20.6% and 1909, 25.7%, respectively). Prevalence was not related to deprivation and varied between wards only for the girls; some wards had very different prevalence rates for boys and girls (Picton: 59 boys, 23.4%; 106 girls, 36.6%). The most deprived ward did not have a remarkable prevalence of overweight or obesity (Speke: 32 boys, 15.3%; 40 girls, 19.8%). CONCLUSIONS: Obesity is a major problem and requires urgent action but targeting intervention on the basis of administrative areas may be very wasteful. Different factors seem to lead to obesity in boys and girls, and attention should be paid to the role of the physical environment.     

Overweight and obesity among Iranian female adolescents in Rasht: more overweight in the lower social group

OBJECTIVE: This study aimed to investigate the frequency of overweight and obesity among Iranian adolescent girls aged 14-17 years and its possible association with maternal education in Rasht city in 2005. DESIGN: A cross-sectional survey on 1054 schoolgirls. SETTING: High schools in Rasht city, Iran. METHODS: A multistage sampling method was used and 1054 randomly selected schoolgirls were studied. Data on age and mother's years of schooling were collected by questionnaire and body weight and height were measured. Overweight and obesity were defined using age- and sex-specific body mass index (BMI) cut-off points proposed by the International Obesity Task Force (IOTF), and compared with 85th and 95th BMI percentile curves of the IOTF reference population, respectively. Data analyses included two groups based on mother's years of schooling: less educated ( < 12 years) and more educated ( > or = 12 years). RESULTS: The overall prevalence of overweight and obesity in this population was 21.9 and 5.3%, respectively. Results of logistic regression analysis showed that the risk of overweight was higher for lower age group (odds ratio = 2.0, 95% confidence interval 0.18-3.09). Overweight was more common in girls with less educated mothers than in girls with more educated mothers (26.0 vs. 19.8%, P = 0.03). CONCLUSION: These data indicate that overweight is highly prevalent among adolescent girls, especially in lower social groups in Rasht, and the rate is exceeding those reported in other parts of the country. Preventive strategies need to be adopted to combat the epidemic of overweight and obesity in this population.     

Obesity and related risk factors among low socio-economic status minority students in Chicago

OBJECTIVES: To assess overweight and related risk factors among urban low socio-economic status (SES) African-American adolescents in an attempt to study the underlying causes of ethnicity and gender disparities in overweight. METHODS: Cross-sectional data collected on anthropometric measures, diet, physical activity and family characteristics from 498 students in grades 5-7 in four Chicago public schools were analysed to study the risk factors for overweight using stepwise regression analysis. RESULTS: Only 37.2% of the students lived with two parents. Nearly 90% had a television (TV) in their bedroom, and had cable TV and a video game system at home. Overall. 21.8% (17.7% boys versus 25.1% girls) were overweight (body mass index (BMI) >/= 95th percentile); and 39.8% had a BMI >/= 85th percentile. Compared with national recommendations, they had inadequate physical activity and less than desirable eating patterns. Only 66.1% reported having at least 20 min vigorous exercise or 30 min of light exercise in >/= 5 days over the past 7 days; 62.1% spent >3 h days- 1 watching TV/playing video games/computer, while 33.1% spent >/= 5 h days- 1. Their vegetable and fruit consumption was low, and they consumed too many fried foods and soft drinks: 55.1% consumed fried food twice or more daily and 19.5% four times or more daily; 70.3% consumed soft drinks twice or more daily and 22.0% four times or more daily on average. Gender, physical activity and pocket money were significant predictors of overweight (P < 0.05). CONCLUSIONS: Several factors in the students' behaviours, school and family environments may increase overweight risk among this population. There is a great need for health promotion programmes with a focus on healthy weight and lifestyle, and targeting urban low-SES minority communities.     

Dietary intake among under-, normal- and overweight 9- and 15-year-old Estonian and Swedish schoolchildren

OBJECTIVES: To determine the differences in macronutrient and food group contribution to total food and energy intakes between Estonian and Swedish under-, normal- and overweight schoolchildren, and to estimate the association between diet and body mass index (BMI). DESIGN: Cross-sectional comparison between Estonian and Swedish children and adolescents of different BMI groups. SETTING: Twenty-five schools from one region in Estonia and 42 in two regions of central Sweden. SUBJECTS: In total 2308 participants (1176 from Estonia and 1132 from Sweden), including 1141 children with a mean age of 9.6 +/- 0.5 years and 1167 adolescents with a mean age of 15.5 +/- 0.6 years. RESULTS: Overweight was more prevalent among younger girls in Sweden (17.0 vs. 8.9%) and underweight among girls of both age groups in Estonia (7.9 vs. 3.5% in younger and 10.5 vs. 5.1% in older age group of girls). Compared with that of normal- and underweight peers, the diet of overweight Estonian children contained more energy as fat (36.8 vs. 31.7%) but less as carbohydrates, and they consumed more milk and meat products. Absolute BMI of Estonian participants was associated positively with energy consumption from eggs and negatively with energy consumption from sweets and sugar. Swedish overweight adolescents tended to consume more energy from protein and milk products. Risk of being overweight was positively associated with total energy intake and energy from fish or meat products. In both countries the association of overweight and biological factors (pubertal maturation, parental BMI) was stronger than with diet. CONCLUSION: The finding that differences in dietary intake between under-, normal- and overweight schoolchildren are country-specific suggests that local dietary habits should be considered in intervention projects addressing overweight.     

The determinants of overweight and obesity among 10- to 15-year-old schoolchildren in the North West Province, South Africa - the THUSA BANA (Transition and Health during Urbanisation of South Africans; BANA, children) study

AIM: To investigate the determinants of overweight and obesity among 10- to 15-year-old schoolchildren in a population in the transitional phase in the North West Province of South Africa.METHODS: A cross-sectional survey was used to investigate weight status (anthropometric indicators) and determinants of overweight/obesity including dietary intake, physical activity and socio-economic status. A single, random sample (n=1257), stratified for gender, type of school and ethnic group, was used. Data were collected on demographics, family circumstances, habitual physical activity, dietary intake and anthropometry to evaluate weight status and body fat content. One-way analysis of variance, the generalised linear models procedure of SAS and the Tukey post hoc honest significant difference test were used to analyse the data.RESULTS: Few children were overweight or obese (7.8%) according to International Obesity Task Force (IOTF) standards (body mass index (BMI)-for-age). These standards were compared with other accepted standard values. Both Cole's IOTF/BMI-for-age standard and the sum of skinfold thicknesses standard classified normal-weight status similarly at a level of 92% (P<0.01) and were found to be useful in determining overweight/obesity. The prevalence rate was higher in females and white children, and was more apparent in urban areas, smaller households and children of parents with low- or high-income occupations. Boys and pre-menarcheal girls had mean body fat percentage in the normal/optimal range, whereas that of post-menarcheal girls was moderately high. Few variables showed a significant association with high body fat percentage: in boys, only the number of members in the household and physical activity levels over the weekend; in girls, only age. The overweight/obese boys mostly lived in smaller households, and the overweight/obese post-menarcheal girls were most inactive on both weekdays and weekends, and more overweight with increasing age.CONCLUSION: Smaller households, inactivity and increasing age for girls were found to be determinants that influence the development of overweight/obesity, while female gender and age post-menarche were identified as determinants of higher body fat content. For overweight/obesity prevention, the focus should be on pre-menarcheal girls, aged 10-13 years, using these determinants to identify overweight/obesity risk. Preventive programmes should aim to increase the physical activity of children to improve their current and future weight status.     

Correlates of childhood obesity in Athens, Greece

OBJECTIVE: Childhood obesity is a growing public health problem. We have examined the association between sociodemographic profile and eating and physical activity patterns with overweight among primary-school students in Athens, Greece. DESIGN: Cross-sectional study. SETTING: Eleven primary schools in the greater Athens area, Greece. SUBJECTS: A total of 633 children aged 10-12 years (50 % boys, 50 % girls) were interviewed in person during spring 2003. Multivariate logistic regression was used to investigate the association between eating and physical activity patterns and overweight (> or =85th sex- and age-specific BMI centile). Results are presented as odds ratios and 95 % confidence intervals. RESULTS: Overweight was more common among girls than among boys (OR=1.73; 95% CI 1.11, 2.69) and substantially less common among children born outside Greece (OR=0.46; CI 0.22, 0.95). Reported physical activity (per 1.5 h per day) was unrelated to overweight (OR=0.97; CI 0.85, 1.12) but patent physical inactivity, operationalised as time spent watching television or working/playing with the computer (per 1.5 h per day) was a highly significant predictor of overweight (OR=1.20; CI 1.05, 1.36). Composition of diet was unrelated to overweight but the daily number of eating occasions, controlling for total energy intake, was significantly inversely associated with overweight (OR=0.61; CI 0.48, 0.76). CONCLUSIONS: The principal factor underlying overweight among children in Athens appears to be the extended inactivity imposed by modern childhood lifestyles. An intriguing finding is that spreading a given energy intake over several eating occasions was inversely associated with the likelihood of childhood obesity.     

Association of body mass index and dietary restraint with changes in eating behaviour throughout late childhood and early adolescence: a 5-year study

OBJECTIVES: To describe patterns of dietary behaviours specific to low quality snacking, fruit and vegetable, and fast food consumption during the transition from childhood to adolescence and to examine how these behaviours are associated with tendencies towards dietary restraint and the occurrence of overweight and obesity in mid-adolescence. DESIGN: A 5-year follow-up of self-reported eating. Hierarchical linear modelling was utilised to explore the relationship between dietary changes and body mass index (BMI) and dietary restraint while controlling for physical activity and smoking. SETTING: The sample was derived from students participating in the Quebec Heart Health Demonstration Project, and represents rural, suburban and inner city youths. SUBJECTS: A sample of 561 girls and 627 boys in the fourth, sixth, seventh and ninth grades. RESULTS: Overall the sample was characterised by a decrease in fruit and vegetable consumption and increase in low quality snacking, and a decrease in fast food consumption over the 5-year follow-up. Dietary restraint and BMI were found to be associated with dietary behaviour. Lower than average dietary restraint was associated with a lower frequency of fast food consumption and greater increase in low quality snacking over the 5-year period. Higher than average dietary restraint was associated with lesser frequency of low quality snacking at baseline. Having a BMI in the obese range was associated with more frequent fast food consumption in the fourth grade and a more rapid drop in fast food consumption across the 5-year period. CONCLUSIONS: Dietary behaviours are associated with the psychological construct dietary restraint and with weight status in this population of adolescents.     

The association between consumption of breakfast cereals and BMI in schoolchildren aged 12-17 years: the VYRONAS study

OBJECTIVE: To evaluate whether consumption of breakfast cereals is associated with BMI in a sample of Greek adolescents. DESIGN: A cross-sectional health and nutrition survey.Setting and subjectsDuring 200417 years were selected from twelve schools located in Vyronas region (Athens metropolitan area). Height and weight were measured and BMI was calculated. A semi-quantitative FFQ was applied and multiple logistic regression analysis was used. RESULTS: Overall, 47 % of girls were obese, whereas 192 % of girls were overweight. Only 205 % of girls reported that they consume cereals as a first choice for breakfast. Consumption of breakfast cereals was associated with lower BMI in boys (P = 0019), irrespective of age and physical activity status. More prominent results were observed for daily cereal consumption or for more than two daily servings of cereals consumed for breakfast. Consumption of pre-sweetened breakfast cereals was associated with lower BMI compared with non-pre-sweetened or no intake of cereals, in both genders (P < 0.001). Consumption of breakfast cereals was associated with 33 % (95 % CI 14 %, 48 %) lower likelihood of overweight/obesity, irrespective of age, sex and physical activity status. CONCLUSIONS: Consumption of breakfast cereals was associated with lower BMI levels and a lower likelihood of overweight/obesity in both genders; thus a solid basis for public health professionals could be built when issuing advice on weight management.     

Misperceptions, inactivity and maternal factors may drive obesity among Barbadian adolescents

OBJECTIVES: To describe (1) the prevalence of overweight and obesity and their association with physical activity; (2) the effect of different cut-off points for body mass index (BMI) on weight status categorisation; and (3) associations of weight status with perceptions of body size, health and diet quality. DESIGN: A cross-sectional study. SETTING: Secondary schools in Barbados. SUBJECTS: A cohort of 400 schoolchildren, 11-16 years old, selected to study physical education practices. RESULTS: Prevalence of overweight (15% boys; 17% girls) and obesity (7% boys; 12% girls) was high. Maternal obesity, as defined by the International Obesity Task Force (IOTF) BMI cut-off points, predicted weight status such that reporting an obese mother increased the odds of being overweight by 5.25 (95% confidence interval: 2.44, 11.31). Physical activity was inversely associated with weight status; however levels were low. Recreational physical activity was not associated with weight status in either category. Overweight subjects tended to misclassify themselves as normal weight and those who misclassified perceived themselves to be of similar health status to normal-weight subjects. The National Center for Health Statistics and IOTF BMI cut-off points produced different estimates of overweight and obesity. CONCLUSIONS: Our findings suggest that inadequate physical activity and ignorance related to food and appropriate body size are promoting high levels of adiposity with a strong contribution from maternal obesity, which may be explained by perinatal and other intergenerational effects acting on both sexes. Prevalence studies and local proxy tools for adiposity assessment are needed.     

Associations of television viewing time with excess body weight among urban and rural high-school students in regional mainland China

OBJECTIVE: To examine the relationship between television (TV) viewing and body mass index (BMI) among adolescents in a region of mainland China. DESIGN: Population-based cross-sectional study, conducted between September and November of 2004, on a sample of enrolled high-school students aged 12-18 years. SETTING: One hundred and sixty-eight classes randomly selected from both urban and rural areas and belonging to 15 senior and 41 junior high schools in Nanjing, China, with a regional population of 6.0 million. SUBJECTS: In total 6848 students participated; 47.7 % from urban and 52.3 % from rural areas; 49.0 % male and 51.0 % female. The response rate among eligible participants was 89.3 %. RESULTS: The proportion of overweight was 6.6 % according to the criteria of overweight recommended for Chinese adolescents. Boys than girls (8.9 % vs. 4.4 %) had higher odds of being overweight (odds ratio (OR) 2.12, 95 % confidence interval (CI) 1.74, 2.60), while the proportion of overweight was significantly lower among rural students than urban students (4.5 % vs. 8.9 %; OR 0.49, 95 % CI 0.40, 0.60). Those students who watched TV for more than 7 h/week had a 1.5 times greater odds of being overweight relative to their counterparts who watched TV for 7 h/week or less (adjusted OR 1.51, 95 % CI 1.24, 1.82). Furthermore, there was a positive linear relationship between TV viewing time and BMI, even after adjusting for age, gender, residence area, time spent in study, in sleeping and in physical activity, and monthly pocket money. CONCLUSIONS: Viewing TV might increase the likelihood of being overweight for Chinese adolescents in China.     

Assessment of obesity and fear of fatness among inner-city Dublin schoolchildren in a one-year follow-up study

BACKGROUND: Positive secular trends in adolescent obesity and an increased prevalence of fear of fatness, particularly among girls, have been documented world-wide. There is a lack of consensus about assessment criteria for childhood obesity and no standard exists for assessing Irish children. In 1990, the Irish National Nutrition Survey used body mass index (BMI) > or =26 kg m(-2) to describe the prevalence of overweight among Irish adolescents. OBJECTIVES: (1) To examine the range in classification of Dublin schoolchildren as overweight according to four standard assessment methods; (2) to assess changes in weight status, prevalence of fear of fatness and accompanying slimming practices in a one-year follow-up; and (3) to compare the prevalence of overweight with that documented in 1990 among adolescents of similar age. DESIGN: A one-year follow-up study of 199 healthy schoolchildren (90 boys and 109 girls; mean age of 11 years at baseline) attending seven fee-paying (six single- and one mixed-sex) and eight non-fee-paying (four single- and four mixed-sex) primary schools in Dublin city centre. MEASUREMENTS: Weight, height, waist circumference and triceps skinfold were measured and used in five definitions of overweight, including published cut-off points of BMI-for-age (Centers for Disease Control and Prevention BMI-for-age charts for boys and girls; BMI reference curves for the UK 1990; International Obesity Task Force age- and sex-specific BMI cut-offs), actual relative weight and BM > or =26 kg m(-2). Assessment of body image perceptions and satisfaction (using figure line drawings) was reported in a questionnaire specifically designed for this study. RESULTS: The prevalence of overweight within the total group differed between the four standard definitions of weight status, by 9% at baseline and 8% at follow-up. Accordingly, increasing trends over the year ranged from zero to 3%. Using the criterion BMI > or =26 kg m(-2), 6% of Dublin schoolchildren were overweight, compared with 1.9% of schoolchildren in 1990. Significantly more girls than boys were affected by fear of fatness and were trying to lose weight. CONCLUSION: A standard method for assessment of weight status is urgently needed for the evaluation of obesity prevention initiatives among Irish schoolchildren. Such initiatives need to be sensitive to the pervasiveness of fear of fatness among adolescent girls.