Changes in BMI and the prevalence of overweight and obesity in children and adolescents in Cracow, Poland, 1971–2000

The aim of this study is to examine changes in prevalence of overweight and obesity, using International Obesity Task Force criteria, in three cohorts of children and youth living in Cracow, Poland, in 1971, 1983 and 2000. Rates of overweight and obesity doubled among boys and girls, from 7.5% and 6.5% in 1971, to 15.2% and 11.8% in the year 2000. The greatest increases in prevalence occurred in the youngest age groups (7–12 years for boys and 7–10 years for girls), increases being less extensive among adolescents, and lowest of all in the oldest age groups (16–18 years in boys and 14–18 years in girls). The absence of a positive secular trend in BMI among adolescent females relative to males may be due to sociocultural pressures associated with transition to a free market economy in Poland. The extent to which girls attempt to achieve the ideal body, as portrayed by media and society more generally, increases across adolescence.     

Body mass index, prevalence of overweight and obesity in Lithuanian children and adolescents, 1985-2002

The study provides the body mass index (BMI), the prevalence of overweight (OW) and obesity (OB) in Lithuanian children and adolescents, 1985-2002. In the 2000-2002 more than 9000 schoolchildren of 7-18 years old were investigated in the 5 biggest towns and surrounding settlements of Lithuania. These data were compared with the 1985 data. The prevalence of OW and OB was estimated using the International Obesity Task Force (IOTF) cut-off points. The prevalence of OW in Lithuanian children and adolescents was higher among younger schoolchildren in comparison with older adolescents. OW was lower among the older girls in comparison with the older boys: 4.60%-11.50%/4.80%0-13.62% in the 7-13 years girls/boys, versus 1.50%-6.60%/3.90%-9.50% in the 14-18 years old girls/boys. The prevalence of OW among younger Lithuanian adolescents did not change significantly in the last 15 years, but it slightly decreased in older boys and demonstrably diminished in older adolescent girls. In generally, the prevalence of OW among Lithuanian adolescents is low in comparison with the prevalence of OW in children from the other countries.     

Trends in the prevalence of overweight and obesity among young Australians, 1985, 1997, and 2004

Objective: To determine secular trends in overweight/obesity among 7‐ to 15‐year‐olds for the periods 1985, 1997, and 2004. Research Method and Procedures: Data from representative surveys conducted in New South Wales, Australia, in 1985, 1997, and 2004 were analyzed. Height and weight were measured, and BMI categories were created using International Obesity Task Force definitions. Students were grouped as Grades 2 + 4 + 6 and 8 + 10. Results: The prevalences of overweight/obesity for 1985, 1997, and 2004 were 10.9%, 20.6%, and 25.7% among the younger boys and 10.6%, 19.5%, and 26.1% among the older boys. The average annual rate of increase for 1985 to 1997 was 0.81% and for 1997 to 2004 was 0.73% among the younger boys and was 0.74% and 0.94% for the two periods among the older boys. The prevalences of overweight/obesity in 1985, 1997, and 2004 were 14.0%, 22.0%, and 24.8% among the younger girls and 8.3%, 17.9%, and 19.8% among the older girls, respectively. The average annual rates of increase for the two periods were 0.8% and 0.4% among the younger girls and 0.80% and 0.27% among the older girls. Change in the prevalence of overweight/obesity and socioeconomic status were not associated. Discussion: Over the period 1985 to 1997, the prevalence of overweight and obesity increased significantly among the younger and older boys and the younger girls. The prevalence of overweight, but not obesity, increased among the older girls over this period. Over the period 1997 to 2004, the prevalence of overweight/obesity combined increased significantly among boys of both age groups but not among girls.     

The extent of overweight index in children and adolescents from Cracow,Poland (1971–2000)

Obesity indices describe the percentage of overweight and obese children in a given population but they do not show the extent to which the norms have been exceeded. The aim of this work was to determine the extent of overweight index (EOW), suggested by Jolliffe, 2004a, Jolliffe, 2004b, by examining children and adolescents from Cracow in order to obtain information on overweight and obesity prevalence and on the amounts by which the BMI age- and sex-specific norms are exceeded, emphasising usefulness of EOW in population studies.The study material comprises three randomly selected groups, representative for Cracow: (1) measured in 1971 which includes 4090 individuals of both sexes and aged 7–19 years, (2) measured in 1983 with 6542 individuals aged 3–19 years and (3) measured in 2000 with 4524 boys and girls aged 3–19 years. The EOW index of overweight is a mean relative deviation from BMI threshold, assuming that for values lower than the threshold ones, the deviation amounts to zero.The EOW index values in boys increased from 0.9 in 1971 up to 2.2 in 2000 i.e. by 144%, indicating an increase of both prevalence of overweight and obesity and an increase of the amount by which the limits of overweight are exceeded. In girls the index also increased, though less dramatically, from 0.7 in 1971 to 1.5 in 2000 i.e. by 114%.An analysis of the results showed that the increasing prevalence of overweight and obesity in children and adolescents is accompanied by an increase of the amount by which the BMI threshold values are exceeded.     

Prevalence of overweight and obesity among the affluent adolescent school children of Amritsar, Punjab

In the present study, an attempt has been made to assess the prevalence of overweight and obesity in adolescent children (between 10-15 years of age) of the affluent families of Amritsar district of Punjab, a state in rapid economic and epidemiological transition. A total of 640 children (323 boys and 317girls) were measured for height and weight. Overweight and obesity were assessed using age and sex-specific body mass index (BMI) cut-off points. 9.91% boys and 11.99% girls were overweight, and 4.95% boys and 6.31% girls were obese. The prevalence of overweight and obesity among the affluent children in Amritsar was as high or higher as in some industrialized countries.     

Racial and ethnic differences in secular trends for childhood BMI, weight, and height

Objectives: The prevalence of childhood overweight in the United States has markedly increased over the last 30 years. We examined differences in the secular trends for BMI, weight, and height among white, black, and Mexican‐American children. Research Methods and Procedures: Analyses were based on nationally representative data collected from 2 to 17 year olds in four examinations (1971–1974 through 1999–2002). Results: Overall, black children experienced much larger secular increases in BMI, weight, and height than did white children. For example, over the 30‐year period, the prevalence of overweight increased ～3‐fold (4% to 13%) among 6‐ to 11‐year‐old white children but 5‐fold (4% to 20%) among black children. In most sex‐age groups, Mexican‐American children experienced increases in BMI and overweight that were between those experienced by blacks and whites. Race/ethnicity differences were less marked among 2 to 5 year olds, and in this age group, white children experienced the largest increase in overweight (from 4% to 9%). In 1999–2002, the prevalence of extreme BMI levels (≥99th percentile) reached 6% to 7% among black girls and Mexican‐American boys. Discussion: Because of the strong tracking of childhood BMI levels into adulthood, it is likely that the secular increases in childhood overweight will greatly increase the burden of adult disease. The further development of obesity interventions in different racial/ethnic groups should be emphasized.     

Biocultural aspects of gender differences in body composition and obesity during childhood and adolescence

Gender differences in body composition, the prevalence in overweight and obesity as well as in physical activity patterns were tested among 3003 children and adolescents aging between 6 and 18 years (x = 12.1 +/- 3.6) in Vienna and rural parts of Eastern Austria. As to be expected, the absolute and relative amount of body fat was significantly higher among girls of nearly all age groups, while boys exhibited a significantly higher amount of lean or fat free body mass. The prevalence of overweight and obesity was markedly higher among prepubertal girls, however significantly lower among younger and older adolescent girls aging 11 years and older in comparison to their male counterparts. This was however only true of adolescents originating from Austria. Considering adolescents with a background of migration originating from Turkey or the Near East, a significantly higher amount of overweight and/or obesity was found among girls. Therefore, biocultural factors have to be considered to explain gender differences in obesity during childhood and adolescence.     

Prevalence of obesity in British children born in 1946 and 1958.

The prevalence of overweight at ages 7 and 11 years and in late adolescence was compared in two nationally representative cohorts of British children born in 1946 and 1958. Overweight was defined as weight that exceeded the standard weight for height, age, and sex by more than 20% (relative weight greater than 120%). The prevalence of overweight among 7 year olds born in 1958 was nearly twice that among those born in 1946. Changes in infant feeding practices, food supply, and level of physical activity might be responsible for this difference. By adolescence the prevalence of obesity in both cohorts had increased but the difference between cohorts had almost disappeared. Around 9% of adolescent girls and 7% of adolescent boys were overweight. If infant feeding practices have an influence on prevalence of overweight at 7 years the data from the two cohorts suggest that such an effect does not persist. In neither cohort was there a significant relation between the prevalence of obesity and social class in boys, but in girls the prevalence was higher among those from the lower socioeconomic groups. Correlation coefficients showing the strength of the relation between relative weights at different ages were remarkably similar for both cohorts. The risk of being obese later in childhood for those who had not been obese at the age of 7 was less than one in 10, whereas for those with a relative weight greater than 130% the risk exceeded six in 10.     

Obesity among male adolescent migrants in Vienna, Austria

Childhood overweight and obesity--especially among migrant children--are health problems in several European countries. The prevalence rates of overweight and obesity among 936 migrant boys of low socio-economic status from Turkey and former Yugoslavia were compared with those of Austrian boys in Vienna. In the longitudinal study, children were measured at the ages of 6, 10 and 15 years. Weight status was estimated by means of the body mass index and percentile curves were used for weight status classification. The prevalence of overweight and obesity was high among migrant boys as well as Austrian boys at all age groups. Ten-year-old boys from Yugoslavia exhibited the highest percentage of overweight (nearly 38%). The lowest percentage of overweight was among 6-year-old Austrian boys (17.2%). Being overweight or obese at the age of 6 years increased the risk of being overweight at 10 and 15 years significantly (p<0.001). This was true of all groups independent of migrant status. The impact of migrant status on weight status at the ages of 10 and 15 was not significant. Therefore, although migrant boys from former Yugoslavia exhibited the highest rates of overweight and obesity, migrant status is not associated significantly with an increased prevalence of obesity in this sample characterized by a generally low socio-economic status. Prevention should start as early as possible for all children, since overweight tends to persist from childhood into adolescence independent of migrant status.     

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 ≥ 95th percentile, and adult obesity was defined as BMI ≥ 30 kg/m². 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.     

Geographic and Demographic Variation in the Prevalence of Overweight Canadian Children

Objective : To examine the geographic and demographic variation in the prevalence of overweight Canadian children. Research Methods and Procedures : Using BMI data from the 1981 Canada Fitness Survey and the 1996 National Longitudinal Survey of Children and Youth, this study assessed: 1) the prevalence of overweight and obesity among Canadian boys and girls ages 7 to 13 years; 2) secular trends in the prevalence of overweight from 1981 to 1996, by province and adjusted for age and sex; and 3) provincial variation in the prevalence of overweight, before and after adjusting for socioeconomic and demographic characteristics. Results : The prevalence of boys and girls classified as overweight in 1996 was 33% and 26%, respectively. The corresponding figures for obesity were 10% for boys and 9% for girls. Provincial variation was observed with a trend of increasing risk of being overweight from west to east. Socioeconomic status was inversely related to the prevalence of overweight regardless of geographic region. The risk of being overweight was more related to geography (province) than demographic variables (income and family background); however, the effect of secular trends (1981 to 1996) exceeded the effect of geographic or demographic variables. Discussion : The prevalence of childhood overweight and obesity is increasing in all areas of Canada and can be explained only partially by geographic or demographic characteristics.     

Overweight trends among Polish schoolchildren before and after the transition from communism to capitalism

This study aims to reveal the secular trends in body mass index (BMI) and the prevalence of overweight and obesity among Polish schoolchildren between the years 1966–2012, during which intense socio-political changes took place. Four surveys were conducted in several districts of Poland looking at 69,746 schoolchildren aged 7–18. Significant increase in mean BMI as well as in the prevalence of overweight and obesity was observed. During this time the highest increase in both mean BMI and excess weight was observed between 1988 and 2012, i.e. after the political transformation, resulting in the improvement of living conditions. However, with respect to girls in late adolescence, between these years, the mean BMI as well as the prevalence of overweight were leveling off, while the percentage of boys with excess body fat in the same developmental category significantly increased in 2012. In the years 1966–1978 and 1978–1988 the pattern of changes in the prevalence of overweight and obesity reflected the social and economic circumstances, i.e. temporary economic improvements, or deepening political crises and food shortage. In conclusion, the weight status of schoolchildren strongly reflects socio-political changes that took place in Poland, as well as in most of the Central European countries in the last half century.     

Trends in body mass index, prevalence of overweight and obesity in preschool Lithuanian children, 1986-2006

The study provides the body mass index (BMI), the prevalence of overweight and obesity in preschool Lithuanian children, 1986-2006. In the 2003-2006 more than 1000 preschool 3-6 year old children from Vilnius (the capital of Lithuania) were investigated according to the standard anthropometric methods. The prevalence of overweight (OW) and obesity (OB) was estimated according to the cut-off points recommended by the International Obesity Task Force (IOTF). Recent data were compared with the data of preschool children from the 1986 Vilnius study and with the data from the other countries. The BMI of preschool children did not change significantly during the last 20 years, except for the statistically significant BMI increment in 6 years old girls. The prevalence of OB among preschool Lithuanian children was low (0.8%-3.7% in boys, and 0-1.9% in girls) and did not change significantly during 1986-2006. The prevalence of OW was higher in preschool girls (10.7%-18.2%) in comparison with preschool boys (6.5%-12.4%). The significant increment of the prevalence of OW was observed among the 6-year-old girls from the 2006 study in comparison with the 1986 study. The possible socio-economic reasons of the defined trend in the BMI and prevalence of OW and OB among preschool Lithuanian children are discussed in the paper.     

Differences in physical activity between non-overweight, overweight and obese children

The purpose of the study was to find out differences in moderate to vigorous physical activity among non-overweight, overweight and obese children, and between boys and girls. The sample included 364 children (179 boys and 185 girls), aged 6.4 years (+/- 0.3 SD). Physical activity was assessed by 7-day questionnaire. Age adapted BMI was used as overweight and obesity indicator. The children were divided into non-overweight, overweight and obese groups. It was found out, that there are significant differences in non-overweight, overweight and obese children (p < 0.05). Boys were significantly (p < 0.05) less moderate to vigorous physical active than girls, especially in indoor activities. There were also significant differences (p < 0.05) in moderate to vigorous physical activity among non-overweight and obese boys and among overweight and obese boys in weekends and total weekly activity. In girls there are significant differences (p < 0.05) in non-overweight, overweight and groups in weekends and total weekly activity. It is possible to conclude, that obese boys and overweight and obese girls, are prone to less physical activity.     

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.     

Prevalence of obesity in elementary schoolchildren living in Northeast Attica, Greece

Objective: To assess the prevalence of obesity and obesity trend in schoolchildren living in Northeast Attica, Greece. Research Methods and Procedures: Mean (standard deviation) and median weight and BMI were calculated in 4131 (2054 boys and 2077 girls) 6‐ to 11‐year‐old Greek schoolchildren living in Northeast Attica between November 2003 and April 2004. Two hundred thirty‐six (95 boys, 141 girls) immigrant children also participated in the study. The secular trend for obesity was determined comparing our data with those of a similar study performed in 1994. Results: Of boys, 27.8% were overweight, and 12.3% were obese. For girls, the corresponding values were 26.5% for overweight and 9.9% for obesity. There was an increase in the prevalence of overweight and obesity in the last 10 years in both sexes. For boys, overweight increased by 4.2% and obesity by 2.9%, whereas, for girls, overweight increased by 3.8% and obesity by 1.6%. Overweight and obesity were less prevalent in the immigrant children compared with their Greek peers. For immigrant boys, overweight was 15.9% and obesity was 7.9%, and for immigrant girls, overweight was 15.2% and obesity was 8.7%. Discussion: Greek schoolchildren living in Northeast Attica present a high prevalence of overweight and obesity and a positive secular change in the prevalence of obesity.     

Obesity and Overweight Prevalence in Polish 7‐ to 9‐Year‐Old Children

Objective: Secular trend in childhood obesity is a well‐known phenomenon, and it is important to monitor it in cross‐sectional studies. The study aim was to estimate prevalence of obesity and overweight in Polish 7‐ to 9‐year‐old children and to compare the results with a French study based on the same protocol. Research Methods and Procedures: The study was conducted in 2001 according to the protocol of the European Childhood Obesity Group. Height and weight were measured, and BMI was calculated to define nutritional status in a randomly selected group of 2916 (1445 girls and 1471 boys) primary school children. Obesity and overweight were estimated according to International Obesity Task Force references with curve for obesity and overweight passing through 30 and 25 kg/m² at age 18, respectively. Results: Overweight (including obesity) was found in 15.4% of Polish children (in 15.8% of girls and 15.0% of boys) and obesity in 3.6% (3.7% of girls and 3.6% of boys) compared with 18.1% of overweight and 3.8% of obese children in French study. There was no significant difference in nutrition status between Polish and French children except for higher frequency of overweight in French 9‐year‐old boys. The same trend of decreasing overweight through age classes was observed in both populations. Discussion: The prevalence of obesity and overweight (including obesity) in prepubertal children estimated in two European countries according to the same protocol and using the same references showed little differences between the two populations despite higher prevalence of obesity in Polish than French adults.     

Obesity and the clustering of cardiovascular disease risk factors in 14-year-old children

Although overweight and obesity in childhood are related to risk factors of cardiovascular (CVD), most studies have examined these relationships separately. Internal cut-points were used to examine the relation of overweight (>85th and ≦90th percentile) and obesity (>90th percentile) to risk factor clustering in a sample of 2731 14-year-old children from Lower Silesia, Poland, examined cross-sectionally in 1996–97. All subjects went through anthropometric and blood pressure measurements, and fasting serum levels of lipid, lipoproteins and glucose were estimated. All risk factor (>90th percentile) prevalence increased greatly at higher levels of Body Mass Index (BMI) (kg/m2). Nearly every second obese child had elevated systolic blood pressure and every third child had elevated serum levels of triglycerides. Among overweight boys 24.7% were found to have at least one risk factor, whereas among obese boys every fourth had at least one risk factor. 25% overweight girls and nearly 18% obese girls showed at least one risk factor. Standardized odds ratios for associations between overweight and obesity, and risk factor clustering, indicated that obese boys were 4.8 times more likely to have an elevated level of at least two factors; the probability increasing to 16.1 in the case of three and more factors in comparison to their lean peers. Obese girls showed more then a 7 time higher probability of having three and more risk factors in relation to their lean peers.     

Overweight in urban schoolchildren assessed by body mass index and body fat mass in Dalian, China

In order to assess overweight in urban schoolchildren (298 boys and 298 girls) aged 9-16 years in Dalian, China, their body height, weight, skinfolds at triceps, biceps, subscapular and suprailiac, and body circumferences of mid-upper arm, waist and hip were measured. The results showed that the prevalence of overweight, based on the United States Centers for Disease Control 2000 reference values using body mass index (BMI), was 22.9% in boys and 10.4% in girls, which was higher than that of indicated in Chinese national surveys of recent decades. More boys were overweight than girls due to excessive increase in body fat, although the prevalence of overweight in girls prevalence increased from 13 years. Discussion here focuses on the effects of behavioral patterns on overweight in Dalian schoolchildren, paying attention to gender difference.