Body Mass Index Reference Research Articles

Obesity in children and adolescents worldwide: current views and future directions--Working Group Report of the First World Congress of Pediatric Gastroenterology, Hepatology, and Nutrition.

Obesity in children and adolescents worldwide: current views and future directions--Working Group Report of the First World Congress of Pediatric Gastroenterology, Hepatology, and Nutrition.

Secular trends in overweight and obesity among Finnish adolescents in 1977-1999.

To study the trends in overweight and obesity among Finnish adolescents in 1977-1999. Mailed surveys every other year. Nationally representative samples of 12, 14, 16 and 18-y-olds (n = 64,147, response rate 78.9%). Overweight and obesity were measured by body mass index (BMI) and relative weight (RW) based on self-reported height and weight. BMI > or = the 85th percentile cut-off point for BMI in each age- and sex-specific group in the entire data set was considered as overweight, and BMI > or = 95th percentile cut-off point as obesity. RW > or = 110% and > or = 120%, calculated as the individual's weight divided by the mean weight in each age- and sex-specific height percentile group in the entire data set, were considered as overweight and obesity, respectively. The trends in overweight and obesity are described by the change in the 85th and 95th percentile cut-off points of BMI over time. The prevalence of overweight and obesity is also reported using BMI reference values recommended for international comparisons. Because of the similarity of the BMI and the RW criteria in classifying adolescents as overweight and obese, only results based on BMI are presented. Overweight and obesity increased linearly in all sex and age groups from 1977 to 1999. Depending on the age group, the average increase in the 85th percentile cut-off point of the BMI per 10 y was 0.6-1.1 kg/m2 in boys and 0.3-0.7 kg/m2 in girls. The 95th percentile cut-off point of the BMI for boys and girls increased by 1.1-1.6 kg/m2 and by 0.6-1.0 kg/m2 per 10 y, respectively. In boys, the increase in overweight and obesity was largest in the two youngest age groups. In girls, the increase in overweight was largest in the oldest age group, and that of obesity both in the 14 and 18-y-olds. Overweight and obesity increased more in boys than in girls in all age groups except in the 18-y-olds among whom the increase was similar in both sexes. Examination of the entire BMI distribution showed that there was little or no change over time at the lower (5th, 15th) and middle (50th) percentiles, but increasing differences at the upper end of the distribution, the increases in the 95th percentile being even more marked than those in the 85th percentile curves. According to international reference values, the age-standardized prevalence of overweight increased in boys from 7.2 to 16.7%, and in girls from 4.0 to 9.8%, between 1977 and 1999. The prevalence of obesity in boys was 1.1% in 1977 and 2.7% in 1999, and in girls 0.4 and 1.4%, respectively. Overweight and obesity increased remarkably among Finnish adolescents from 1977 to 1999. The changes concentrated at the upper end of the BMI distribution, suggesting that factors behind this development have influenced only a part of the adolescent population.

Body mass index reference values (mean and SD) for Swedish children

Body mass index (BMI) is an important indicator of nutritional status. Many studies have been done to present BMI reference values in centile values rather than mean and SD values since its statistical distribution is positively skewed. Both height and weight growth charts are usually available in terms of mean and 1, 2 and 3 SD around the means; it would be of clinical value to produce BMI reference charts in a similar way. The aim of this work was to derive the mean and ±1, 2 and 3 SD BMI reference ranges as a supplement to the BMI centile reference values published previously for the same group of Swedish children. The method was based on an age‐dependent Box transformation, and the β‐value was given as a third‐degree polynomial function over the paediatric age. The BMI reference values can be given from mathematical functions in addition to values for specific ages. Conclusion: The BMI reference values and charts derived as described effectively reflect the nature of the variant age‐dependent positive skewed statistical distribution of BMI values in the population, and can serve as a valid supplementary tool in the evaluation of growth and nutrition during paediatric years.

Body mass index reference values (mean and SD) for Swedish children.

Body mass index (BMI) is an important indicator of nutritional status. Many studies have been done to present BMI reference values in centile values rather than mean and SD values since its statistical distribution is positively skewed. Both height and weight growth charts are usually available in terms of mean and 1, 2 and 3 SD around the means; it would be of clinical value to produce BMI reference charts in a similar way. The aim of this work was to derive the mean and +/- 1, 2 and 3 SD BMI reference ranges as a supplement to the BMI centile reference values published previously for the same group of Swedish children. The method was based on an age-dependent Box transformation, and the beta-value was given as a third-degree polynomial function over the paediatric age. The BMI reference values can be given from mathematical functions in addition to values for specific ages. The BMI reference values and charts derived as described effectively reflect the nature of the variant age-dependent positive skewed statistical distribution of BMI values in the population, and can serve as a valid supplementary tool in the evaluation of growth and nutrition during paediatric years.

Prevalence of overweight and obesity in children and adolescents in a county in Sweden

Overweight among young people in Sweden is increasing. The aim of the present study was to investigate the frequency of overweight and obesity based on body mass index (BMI) values among children and adolescents. Overweight was defined as a BMI value > or = 91st percentile and obesity as a BMI value > 98th percentile on an international reference BMI curve. The study population included boys and girls from four age groups: 9, 12, 15 and 18 y. The data consisted of self-reported measures of height and weight that were obtained from questionnaires used in a cross-sectional study in December 1997. A validation study was performed using a part of the study population. A total of 7011 (81.7%) participants completed the questionnaire. The correlation between self-reported estimations and objective measures of height and weight was high in the oldest age groups (0.88-0.98), but lower in the 9-y-old age groups (0.37-0.72). These self-reported estimations in the 9-y-olds were excluded from further analysis. It was found that 12.3%, 11.6% and 11.4% of the boys in the 12-, 15- and 18-y-old age groups and 6.8%, 5.5% and 4.8% of the girls in the same age groups were overweight and 7.9%, 8.9% and 7.3% of the boys and 5.1%, 4.2% and 3.9% of the girls were obese. The prevalence of overweight and obesity was found to be high in the study population and is a serious public health problem. The prevalence of obesity was significantly higher (p < 0.05) in 15-y-old boys living in rural areas than in city and town dwellers of the same age.

Prevalence of overweight in US children: comparison of US growth charts from the Centers for Disease Control and Prevention with other reference values for body mass index

Several different sets of reference body mass index (BMI) values are available to define overweight in children. The objective of this study was to compare the prevalence of overweight in US children calculated with 3 sets of reference BMI values: the revised growth charts of the Centers for Disease Control and Prevention (CDC-US growth charts), international standards proposed by Cole et al, and values developed by Must et al. Data for children and adolescents came from cross-sectional nationally representative US surveys: cycles II and III of the National Health Examination Survey (1963-1965 and 1966-1970) and the first, second, and third National Health and Nutrition Examination Surveys: NHANES I (1971-1974), II (1976-1980), and III (1988-1994). The reference values of Cole et al equivalent to a BMI of 25 were compared with the 85th percentiles from the other 2 methods; the values equivalent to a BMI of 30 were compared with the 95th percentiles. The 3 methods gave similar but not identical results. The reference values of Cole et al gave lower estimates than did the CDC-US growth charts for young children but higher estimates for older children. The reference values of Must et al gave much higher prevalences for younger girls than did the other 2 methods. Differences between methods were related to differences in data sets, smoothing methods, and theoretical approaches. All 3 methods are based on statistical criteria and incorporate arbitrary assumptions. These methods should be used cautiously, with awareness of the possible limitations.

Prevalence of overweight and obesity in children and adolescents in a county in Sweden

Overweight among young people in Sweden is increasing. The aim of the present study was to investigate the frequency of overweight and obesity based on body mass index (BMI) values among children and adolescents. Overweight was defined as a BMI value 91st percentile and obesity as a BMI value 98th percentile on an international reference BMI curve. The study population included boys and girls from four age groups: 9, 12, 15 and 18 y. The data consisted of self-reported measures of height and weight that were obtained from questionnaires used in a cross-sectional study in December 1997. A validation study was performed using a part of the study population. A total of 7011 (81.7%) participants completed the questionnaire. The correlation between self-reported estimations and objective measures of height and weight was high in the oldest age groups (0.88–0.98), but lower in the 9-y-old age groups (0.37–0.72). These self-reported estimations in the 9-y-olds were excluded from further analysis. It was found that 12.3%, 11.6% and 11.4% of the boys in the 12-, 15- and 18-y-old age groups and 6.8%, 5.5% and 4.8% of the girls in the same age groups were overweight and 7.9%, 8.9% and 7.3% of the boys and 5.1%, 4.2% and 3.9% of the girls were obese. Conclusion: The prevalence of overweight and obesity was found to be high in the study population and is a serious public health problem. The prevalence of obesity was significantly higher (p <0.05) in 15-y-old boys living in rural areas than in city and town dwellers of the same age.

Euro‐Growth References for Body Mass Index and Weight for Length

ABSTRACTBackground:Fully longitudinal data from the multicenter Euro‐Growth study (21 study sites;n = 2145 children) were used to develop sex‐specific percentiles and z‐scores for body mass index (BMI) and weight for length (WfL) during the first 36 months of life.Methods:Smoothed percentile curves for BMI against age were constructed and checked against raw percentiles. Smoothed percentile curves for WfL were constructed according to established procedures and were checked against raw percentiles. The relation of BMI with length and of WfL with age was examined. The relation between BMI and WfL was tested using z‐scores of each. The influence of gender, geographic location (study site), and genetic factors on BMI and WfL was examined. Finally, the new references for BMI and WfL were compared with other published references.Results:Selected percentiles (P; P3, P5, PI0, P25, P50, P75, P90, P95, and P97) for BMI showed a sharp increase from 1 to 6 months of age and a gradual decline between 12 and 36 months. Smoothed percentiles for WfL showed only small deviations from raw percentiles. BMI was found to be essentially independent of length, whereas WfL showed some degree of dependence on age. Values for BMI and WfL showed very good agreement, except at the extremes of the age range. A modest degree of influence of geographic location on BMI and WfL was found. Correlations with parental BMI and WfL were very weak, however. Comparison with the National Center for Health Statistics (NCHS) references showed the latter to have a narrower range of values.Conclusions:The new Euro‐Growth references for BMI and WfL provide improved tools for health workers and researchers dealing with childhood obesity.

Euro-Growth references for body mass index and weight for length. Euro-Growth Study Group.

Fully longitudinal data from the multicenter Euro-Growth study (21 study sites; n = 2145 children) were used to develop sex-specific percentiles and Z-scores for body mass index (BMI) and weight for length (WfL) during the first 36 months of life. Smoothed percentile curves for BMI against age were constructed and checked against raw percentiles. Smoothed percentile curves for WfL were constructed according to established procedures and were checked against raw percentiles. The relation of BMI with length and of WfL with age was examined. The relation between BMI and WfL was tested using z-scores of each. The influence of gender, geographic location (study site), and genetic factors on BMI and WfL was examined. Finally, the new references for BMI and WfL were compared with other published references. Selected percentiles (P; P3, P5, P10, P25, P50, P75, P90, P95, and P97) for BMI showed a sharp increase from 1 to 6 months of age and a gradual decline between 12 and 36 months. Smoothed percentiles for WfL showed only small deviations from raw percentiles. BMI was found to be essentially independent of length, whereas WfL showed some degree of dependence on age. Values for BMI and WfL showed very good agreement, except at the extremes of the age range. A modest degree of influence of geographic location on BMI and WfL was found. Correlations with parental BMI and WfL were very weak, however. Comparison with the National Center for Health Statistics (NCHS) references showed the latter to have a narrower range of values. The new Euro-Growth references for BMI and WfL provide improved tools for health workers and researchers dealing with childhood obesity.

Body index measurements in 1996–7 compared with 1980

OBJECTIVESTo compare the distribution of body mass index (BMI) in a national representative study in The Netherlands in 1996–7 with that from a study in 1980.METHODSCross sectional data on height,...

Body mass index in 17-year-old Israeli males of different ethnic backgrounds; national or ethnic-specific references?

To evaluate whether a single national reference is appropriate for assessing prevalence of overweight in heterogeneous populations, or whether ethnic-specific references are needed. A population-based study of Israeli Jewish males who underwent routine physical and clinical examinations prior to army recruitment served as the basis for the development of two types of references for body mass index (BMI): a national reference (NR) and an ethnic-specific reference (ER). Consecutive cohorts of all 17-y-old Jewish male recruits (n=109, 570). Weight, height and blood pressure values were obtained. BMI was calculated, and the 85th percentile of BMI was used as a cut-off point for overweight, using both types of references. Prevalence of hypertension among recruits was used as a biomarker to support the reliability of the ER when discrepancy in classification between the two references was found. As compared to the NR, three ethnic groups had a BMI distribution shifted to the left (light sub-population) and five were shifted to the right (heavy sub-population). In the light sub-population, 7% of the inductees who were classified as having normal weight by the NR were considered overweight by the ER and had a hypertension rate similar to that of those defined as overweight by both references (3.1 per 1000). In the heavy sub-population the 4% of subjects who were overweight by NR and normal by ER had hypertension rates similar to those defined as normal weight by both references (2.7/1000), and significantly lower than that of those classified as overweight by both references (10.8/1000). In heterogeneous populations, ethnic references should be used to evaluate prevalence of overweight, rather than one national reference. International Journal of Obesity (2000)24, 88-92

SHORT REPORT: Suitability of revised UK reference data for the assessment of nutritional status in 7‐year‐old children

Summary Introduction: Nutritional assessment in clinical practice and epidemiology requires comparison of anthropometric measurements with appropriate reference data, but the reference data recommended for the UK are largely untested. The aim of the present study was to test the suitability of the ‘Revised UK 1990’ reference data for height, weight and body mass index (BMI) in a representative sample of 7‐year‐old children. Methods: Measurements made in 255 children in Edinburgh (n=123 girls; 132 boys) were compared with the ‘Revised UK 1990’ reference data using standard deviation (SD) scores. The proportion of children both expected and observed to fall below the 10th centile and above the 90th centile were calculated. Results: In boys, mean (±SD) scores were not significantly different from zero for height (−0.02±0.95), weight (0.07±1.01) and BMI (0.10±1.03), and there was good agreement between expected and observed frequencies &lt;10th and &gt;90th centiles for all three variables. In the girls, mean (±SD) scores did not differ significantly from zero: height (−0.08±0.91); weight (−0.18±0.98); BMI (−0.18±1.02), and there were no significant differences relative to the 10th and 90th centile cut‐offs for height and BMI. Conclusion: This study supports the use of the currently recommended height, weight and BMI reference data to define under‐ and over‐weight for height in children.

Introducing the Adolescent Body Mass Index: A Conceptual and Developmental Process

In 1998, the United States Department of Agriculture's Food and Nutrition Service distributed yourSELF Middle School Nutrition Education Kino 27,000 middle and junior high schools. The kit materials introduce the Body Mass Index (BMI) reference charts to adolescents to provide them with an objective self-assessment tool. Many adolescents have unrealistic body images and rely on subjective perspectives on their size and shape. The BMI is presented in a user-friendly approach, as a self-assessment, self-monitoring tool to help adolescents understand the relationship between their body size and weight. The introduction of the a BMI for children, which differs from the BMI for adults, generated thoughtful discussions in the development process. The BMI educational content was developed through interactive discussions from a BMI Expert Panel, representing 7 federal or academic organizations. The content was tested through individual interviews with adolescents and parents, field tested, and reviewed by 35 Technical Reviewers. It was then cleared in a joint interagency review by 30 federal agencies. The BMI charts in yourSELF will help adolescents take an objective look at their body size and weight. Related information provides general guidelines that support making positive health choices. Too many adolescents have developed unhealthy patterns of eating and inactivity, and unrealistic body images. The materials encourage students to plot BMI two or three times a year to see change occurs over time. The Teacher Guide and Student Guide address the fact that teens are sensitive about changes in their growing bodies. Since teens are still growing, it is not always clear if they are overweight or not. Students are encouraged to talk with their family and a doctor about their growth pattern. The BMI chart offers an objective basis for discerning when an adolescent might need to be referred to a health provider. Although the BMI is not a perfect tool, it is the best single measure for looking at long term health risks of adolescent fatness.

Body Mass Index reference curves for Iran

Body Mass Index (BMI) charts for boys and girls aged 2-18 years in Iran are presented. The charts are based on a random cluster sample survey of 1702 boys and 1599 girls living in urban Tehran, whose height and weights were measured in the 1990-1992 National Health Survey of the whole country. Charts were constructed using Healy's method as modified by Pan, Goldstein and Yang (1990), and for boys at one point were smoothed manually. The resulting charts are shown to fit the data well and adequately describe raw BMI centiles of urban and rural children elsewhere in Iran. Comparison of these BMI charts with corresponding UK charts showed substantial differences at every age and emphasizes the necessity for the use of locally based BMI norms for assessing body mass of Iranian children.

Birth ponderal index and body mass index reference curves in a large population.

A file of 100,716 children born between 1984 and 1988 in 22 maternity wards was used to estimate for each week of gestational age and gender, the exponent β which makes an index Weight/Lengthβ independent from length. It varied with gestational age but remained near 3. Therefore, Rohrer's index (Weight/Length3 ) appears as a good approximation to assess neonatal weight as a whole, taking length into account. However, literature suggests that Quetelet's index (Weight/Length2 ) might be a better indicator of fat mass. In both cases, percentile curves take gestational age into account. Curves by gestational age between 32 and 42 weeks of amenorrhea and by gender, for Quetelet's and Rohrer's indices have been plotted. The values vary with gestational age. For example, the tenth percentile of Quetelet's index shifts from 7.8-12.3 kg/m2 in boys and from 7.9-12.2 kg/m2 in girls. Am. J. Hum. Biol. 10:327-340, 1998. © 1998 Wiley-Liss, Inc.

Body mass index reference curves for Chinese children

SummaryThe Hong Kong Growth Survey 1993 provided data for the construction of reference curves for body mass index (BMI) of Chinese children from birth to 18 years. Data on weight and height was obtained from 11 797 boys and 12 168 girls. The LMS method was used to smooth the percentile curves. These curves showed a definite physiological rising pattern to a peak at 6 months, then fell to a trough at 6 years, before another rise towards adulthood. Compared to published reports from the US, Britain, France and Sweden, Hong Kong Chinese children, particularly the girls, were less obese. In the first 2 years median curves of Hong Kong Chinese were similar to those of the Japanese.

Birth ponderal index and body mass index reference curves in a large population

A file of 100,716 children born between 1984 and 1988 in 22 maternity wards was used to estimate for each week of gestational age and gender, the exponent β which makes an index Weight/Lengthβ independent from length. It varied with gestational age but remained near 3. Therefore, Rohrer's index (Weight/Length3) appears as a good approximation to assess neonatal weight as a whole, taking length into account. However, literature suggests that Quetelet's index (Weight/Length2) might be a better indicator of fat mass. In both cases, percentile curves take gestational age into account. Curves by gestational age between 32 and 42 weeks of amenorrhea and by gender, for Quetelet's and Rohrer's indices have been plotted. The values vary with gestational age. For example, the tenth percentile of Quetelet's index shifts from 7.8–12.3 kg/m2 in boys and from 7.9–12.2 kg/m2 in girls. Am. J. Hum. Biol. 10:327–340, 1998. © 1998 Wiley-Liss, Inc.

Body mass index reference curves for children aged 3-19 years from Verona, Italy.

To compile curves for Body Mass Index (BMI) for Italian children and adolescents. Cross sectional study. All primary and secondary schools of Verona, Italy between October 1986 and January 1987. 20,796 males and 21,073 females children, aged 3-19 y. Weight and height were measured using Salus balances, and age in days was calculated between the date of measurement and that of birth: centiles of BMI by age were calculated by the LMS method of Cole (1990). The centiles obtained were similar to those obtained in UK by Cole et al, 1995. Compared to Cachera's data for France and Hammer's for USA, our BMI values are higher, though closer to the American than the French ones.

Body Mass Index of Saudi Children Ages Six to 16 Years From the Eastern Province

Body mass index (BMI) is generally accepted as a useful index of various clinical situations related to obesity. However, there are no reference BMI charts for Saudi children; this paper is an attempt to establish these. A total of 21,638 Saudi schoolchildren between ages six to 16 years (49.6% males) were studied. Curves for BMI, seven percentiles - 5th, 10th, 25th, 50th, 75th, 90th and 95th - were constructed. As a reference material, BMI data for American children were modified into Hegira years. It was found that, in agreement with others, the BMI for the Saudi children studied was age- and gender-dependent. Comparison between Saudi data and international reference showed the expected genetic influence. These results remain to be compared with those from other regions in the Kingdom.