Ethnic variation in the prevalence of obesity in North American children and youth

Parental Education or Household Income? Which Socioeconomic Status Indicator Can Better Reduce Body Mass Index Disparities among Latino Children?

Aim

We compared the effects of parental education and household income on children's body mass index (BMI) in Hispanic White (HW) and non-Hispanic White (NHW) families.

Methods

In this cross-sectional study, we borrowed data from the Adolescent Brain Cognitive Development (ABCD) study and analyzed data of 5100 children between the ages of 9 and 10. The independent variables were parental education and household income. The primary outcome was BMI value. Ethnicity was the moderating variable. Confounders were age, sex, and family structure. Three mixed-effects regression models were used for data analysis.

Results

Overall, higher parental education and household income were associated with lower BMI levels in children. While an interaction was found between ethnicity and parental education, no interaction was noted between ethnicity and household income regarding BMI. The interaction indicated weaker protective effects of high parental education on BMI in HW children than NHW children. Household income showed similar protective effects on children's BMI in HW and NHW families.

Conclusion

Parental education but not household income loses some of its protective effects on childhood BMI among HW families compared to NHW families. Distal social determinants of health may be more vulnerable to the MDRs (minorities' diminished returns) than proximal ones. As a result, closing the income gap may be a good strategy towards closing the childhood BMI gap between highly educated HW and NHW families. Policies that raise the minimum wage and those that help HW families save money (e.g., earned income tax policies) maybe more promising strategies to eliminate the ethnic gap in BMI than increasing the education level of ethnic minority families.

School-based health promotion intervention: parent and school staff perspectives

BACKGROUND

The prevalence of childhood obesity is high, particularly among minority youth. The objective of this article was to evaluate parent and school staff perspectives of childhood health and weight qualitatively to guide the development of a school-based obesity prevention program for minority youth.

METHODS

Hispanic parents (N = 9) of first graders participated in 1 of 3 focus groups, consisting of 3 parents each. School staff (N = 7) participated in 1 focus group. All sessions were digitally recorded and transcribed verbatim. Using NVivo, 2 independent coders rated the transcriptions to identify themes and a third coder addressed commonalities and discrepancies in the coding schemes.

RESULTS

Parents and school staff have conflicting views over whose responsibility it is to provide nutritional education and participation in physical activity (PA). Parents felt the school should teach children about healthy nutrition, provide guidance in the cafeteria, and offer more structured PA in school. In contrast, school staff noted that parents have the primary responsibility of ensuring children get adequate nutrition and PA.

CONCLUSIONS

Despite contrasting views, parents and staff agreed with the need for comprehensive school-based obesity prevention efforts emphasizing parent and teacher collaboration to promote healthy school and home environments.

Prevalence of overweight and cardiovascular risk factors in rural and urban children from Central Asia: the Kazakhstan health and nutrition examination survey

Kazakhstan is undergoing a rapid modernization process, which carries the risk of an epidemic of obesity and cardiovascular disease. We enrolled a sample of about 50 children for every combination of gender, environment (urban vs. rural), ethnic group (Kazakh vs. Russian), and age group from 7 to 18 years, for a total of 4,808 children. Anthropometry and blood pressure were measured on all children while fasting blood cholesterol and glucose were measured only in 2,616 children aged > or =12 years. The prevalence of overweight and risk of overweight ranged from 2.8 (rural male Kazakhs) to 9.1% (urban male Russians). The prevalence of prehypertension and hypertension ranged from 8.3 (urban females) to 15.9% (rural females); that of hypercholesterolemia from 11.5 (male rural Russians) to 26.5% (female rural Kazakhs); and the overall prevalence of impaired fasting glucose was 0.1%. We conclude that overweight and cardiovascular risk factors are less prevalent in children living in Kazakhstan than in those living in Western countries. However, these figures are not negligible and suggest that preventive measures are needed to contain the epidemic of overweight and cardiovascular disease that will most likely accompany the modernization of Kazakhstan in the next years.

Overweight and obesity in a rural Amerindian population in Oaxaca, Southern Mexico, 1968-2000

The purpose of this study was to evaluate secular change in the prevalence of overweight and obesity in a rural Zapotec Indian community in southern Mexico between 1968 and 2000. Cross-sectional surveys of children 6-13 years, adolescents 13-17 years, and adults 19 years of age and older resident in a rural community in Oaxaca were conducted in 1968/1971, 1978, and 2000. Individuals present in the 1968, 1978, and 2000 surveys provided a small longitudinal component. Height and weight were measured; the BMI was calculated. International criteria for overweight and obesity were used. Overweight and obesity were virtually absent in school children 6-13 years in 1968 and 1978 and in adolescents in 1978. Small proportions of children (boys, 5%; girls, 8%) and adolescents (boys, 3%; girls, 15%) were overweight in 2000; two children (1%) and no adolescents were obese. Among adults, 7% of males and 19% of females were overweight and <1% of males and 4% of females were obese in 1971/1978, but 46% of males and 47% of females were overweight; and 5% of males and 14% of females were obese in 2000. The trends for children, adolescents, and adults were confirmed in the longitudinal subsamples. In conclusion, overweight and obesity are not presently a major problem in children and adolescents in this rural Zapotec community. Overweight, in particular, and to a lesser extent obesity have increased in prevalence among adults since the late 1970s. The results suggest adulthood as a critical period for onset of overweight and obesity in this sample.

Is rural residency a risk factor for overweight and obesity for U.S. children?

OBJECTIVE

Despite studies suggesting that there is a higher prevalence of overweight or obese children in rural areas in the U.S., there are no national studies comparing the prevalence levels of overweight or obese rural to metropolitan children. The objective of this research was to examine the hypothesis that living in a rural area is a risk factor for children being overweight or obese.

RESEARCH METHODS AND PROCEDURES

Using the National Survey of Children's Heath, the prevalence of overweight and/or obese rural children was compared with that of children in metropolitan settings. Multivariate analyses were performed on the data to detect if differences varied by health services use factors or demographic factors, such as household income, gender, and race.

RESULTS

Multivariate analysis revealed that overweight or obese children >or=5 years of age were more likely to live in rural rather than metropolitan areas (odds ratio = 1.252; 95% confidence interval, 1.248, 1.256). Rural overweight U.S. children >or=5 years of age of age were more likely than their metropolitan counterparts to: be white, live in households <or=200% of the federal poverty level, have no health insurance, have not received preventive health care in the past 12 months, be female, use a computer for non-school work >3 hours a day, and watch television for >3 hours a day. In addition, they were more likely to have comorbidities.

DISCUSSION

Living in rural areas is a risk factor for children being overweight or obese.

Obesity and the African-American Adolescent in Mississippi: An Overview

Obesity is one of the most common conditions seen in medical practice, and is one of the most difficult to treat. This condition is often perceived as a cosmetic problem, but it is associated with a number of chronic medical conditions including, but not limited to, heart disease, hypertension, and dyslipidemia. Youth obesity has increased at an alarming rate in the United States and in other developed countries around the world. Given the high prevalence of obesity among adults in the United States, it is not surprising that pediatric obesity is also on the rise. The current trends in obesity among African-American adolescents in the state of Mississippi remain alarming and disheartening. Since obesity starts in early childhood and extends into the adolescent years and possibly into adulthood, behavior modification is the key to preventing the onset of obesity in all population groups.

Methodological issues in the anthropometric assessment of Hmong children in the United States

The effectiveness of the body mass index (BMI; kg/m2) in assessing overweight/obesity may be diminished in populations of short stature. In a sample (n = 79) of Hmong refugee children in the United States, of age 4-11 years, median z scores for height, BMI, and the triceps skinfold were -1.04z, +0.53z, and +0.18z, respectively. Further, 41.7% of children were above the NHANES 85th percentile for BMI-for-age, categorizing them as overweight/obese. Assessment of obesity by other established criteria for children, such as the triceps skinfold and body fat percentage, produced significantly lower estimates than did BMI. This is consistent with patterns found in other stunted populations, suggesting that BMI be employed in conjunction with other methods when assessing overweight/obesity in these groups. Finally, although stunting and overweight/obesity were both common in this study, at the individual level height z scores were positively correlated to z scores of various measures of adiposity.

Growth status and obesity of Hopi children

The purpose of this study was to examine the growth status and prevalence of underweight, overweight, and obesity in Hopi children. Subjects were 263 (117 males, 146 females) Hopi children 6-12 years of age. Stature and mass were measured and the body mass index (BMI) was calculated. Body size variables were plotted relative to age- and sex-specific reference data and the prevalence rates for underweight, overweight, and obesity were estimated using the BMI as the criterion. Age-specific sex differences were compared using independent samples t-tests. In both sexes, mean age-specific stature appeared to be relatively stable around the 50th percentile of reference values. Mean age-specific mass appeared to be relatively stable between the 50th and 90th percentiles of the reference values, while the mean BMI tended to fluctuate about the 85th percentile. Approximately 23% of Hopi children were classified as overweight and an additional 24% were classified as obese. Only two subjects were categorized as underweight. The results are consistent with other reports that childhood obesity is a serious public health concern among Native Americans. Further study is warranted to examine the causes of the high prevalence rates of pediatric obesity among Native Americans and the effectiveness of prevention and intervention programs.

Biocultural aspects of obesity in young Mexican schoolchildren

Obesity related to over-nutrition is investigated in a sample of 219 Mexican children from affluent families, ages 6-12 years. Defined as weight-for-age at or above the 95(th) percentile, obesity rates in middle childhood are very high in this population, being 24.2% of children (29.4% of boys and 19.1% of girls). Binary logistic regression shows that children are more likely to be obese if they are boys, from small households with few or no other children, and have more permissive, less authoritarian parents. Diet at school and activity patterns, including television viewing, are not different for boys and girls and so do not explain this gender variation. The value placed on children, especially sons, in smaller middle-class families, can result in indulgent feeding because food treats are a cultural index of parental caring. Parents also value child fatness as a sign of health. These obese Mexican children have no greater social problems (peer rejection or stigma) or psychological problems (anxiety, depression, or low self esteem) than their non-obese peers. More study specifically focused on feeding practices in the home environment is required to explain very high rates of child obesity. The differences in obesity risk related to specific aspects of children's developmental microniche emphasize the importance of including a focus on gender as a socio-ecological construct in human biological studies of child growth, development, and nutrition.

Childhood overweight problem in a selected school district in Hawaii

Anthropometric measurements were collected from 1,437 public school students in a selected school district in Hawaii every year from 1992 to 1996. Results showed that boys and girls of Hawaiian ancestry (HA) are generally taller in stature and somewhat heavier in weight than their non-Hawaiian counterparts (Non-HA). Also, there are no clear differences between the two groups in BMI, sums of skinfolds, waist and hip circumferences, and waist/hip circumference ratios. When compared to data from NHANES III (Centers for Disease Control and Prevention), the median statures of HA boys and girls are very close to the median statures of NHANES III, but the body weights of HA are heavier at most ages. Also, the BMI values of HA are distinctly higher and their medians are closer to the 75th percentile of NHANES III. In addition, the values of the sums of skinfolds and the waist and hip circumferences of HA are also higher at most ages than NHANES III. These multiple anthropometric indicators suggest that there might be more overweight children and adolescents of HA. When compared to the statistics in NHANES III, there are twice as many HA and Non-HA boys and girls classified as obese. Clearly, a serious childhood problem exists among the children in this selected school district in Hawaii. More research is needed in other school districts in Hawaii. Also, it is suggested in this study that using multiple anthropometric indicators, rather than a single one, may be more accurate and appropriate in determining overweight problems in a youth population.

Childhood obesity in Canada: a review of prevalence estimates and risk factors for cardiovascular diseases and type 2 diabetes

Childhood obesity in Canada has become increasingly prevalent over the past 2 decades. Despite inconsistencies regarding different anthropometric indicators, cut-offs, and reference populations, both regional and national investigations have revealed high numbers of overweight and obese children and adolescents. A number of risk factors and health consequences have been associated with increased levels of body fatness in youth. Specifically, risk factors for cardiovascular diseases (CVD) and type 2 diabetes are known to develop early in life and tend to emerge in clusters among overweight youngsters. Unhealthy lifestyle behaviours (i.e., physical inactivity), a genetic disposition, and a centralized body fat distribution, all contribute to increased risk. In order to prevent future generations of children from experiencing increased morbidity and mortality as overweight and obese adults, coordinated efforts at all levels (family, school, community, and government) must be established with a long-term commitment to promote healthy nutrition and physical activity behaviours in our youth.

Blood pressure is associated with body mass index in both normal and obese children

Obesity is associated with elevated blood pressure (BP) both in adults and children. Childhood obesity has become a severe health problem, especially during the last few decades. So far there has not been any large-scale study specifically focusing on the association between obesity and BP in early life. The aim of this study is to examine systematically the association between obesity and BP in preschool Chinese children in mainland China. In 1996, measurements of weight, height, and BP values were collected in a nationwide, case-control study of 748 boys and 574 girls who ranged in age from 0.1 to 6.9 years in 8 cities in mainland China. One obese child and 1 nonobese child were matched for gender and age. The BP differences of the mean-matched pair were approximately 5 mm Hg for systolic blood pressure (SBP) and approximately 4 mm Hg for diastolic blood pressure (DBP) (P<0.05); a higher value was noted in obese children. The BP value of 19.4% children in the obese group and 7.0% children in the nonobese group was higher than the 95th percentile value (P<0.0001), which is defined as high BP by the Task Force on Blood Pressure Control in Children. Both SBP and DBP were significantly (P<0.05) positively related to body mass index (BMI) values (P<0.05) for children in obese and nonobese groups after adjustment for age, gender, and height. To be specific, an increase of 1 BMI unit was associated with, on average, an increase of 0.56 mm Hg and 0.54 mm Hg in SBP and DBP, respectively, for obese children. In nonobese children, the increase in SBP and DBP was 1.22 mm Hg and 1.20 mm Hg, respectively. An increase in the BMI is conclusively associated with elevated SBP and DBP in nonobese children. Furthermore, an increase in the adjusted BMI was associated with an increase in SBP and DBP in obese and nonobese children.

Food consumption, activity, and overweight among elementary school children in an Appalachian Kentucky community

In the U.S., child overweight is on the rise and is implicated in later adult chronic illness. Given that overweight is hardly tractable, prevention as compared to treatment is seen as a better alternative for lowering the risk of long-term health consequences. To increase the success of prevention efforts, many argue that programs must be "culturally sensitive and targeted toward specific populations at greater risk. However, there exists a limited understanding of how overweight is distributed across the landscape, among and within populations and groups. This paper reports the prevalence of overweight among 54 school children in a rural, Appalachian community with a high rate of poverty, and it compares boys to girls. Thirty-seven percent of boys and 10.3% of girls are overweight, based on the 90th percentile body mass index (BMI). Analysis of food intake indicates a pattern of food consumption that is high in fatty and sugary foods and low in fruit and vegetable consumption. Analysis of activity indicates that children report more low-intensity activity than high; that overweight children report more episodes of video/computer play compared to nonoverweight children; and that boys spend more time than girls in front of the computer/television screen.

Knowledge, skills, and behavior improvements on peer educators and low-income Hispanic participants after a stage of change-based bilingual nutrition education program

A nutrition education program, entitled La Cocina Saludable, was designed according to the Stage of Change Model and implemented in ten southern Colorado counties. The objectives were to improve the nutrition related knowledge, skills, and behaviors that lead to healthy lifestyles in a low-income Hispanic population. The content of the program included nutrition information designed to help mothers of preschool children provide for their children's nutritional needs. Previous studies suggest that low-income Hispanics often demonstrate low intakes of vitamins A and C, calcium, iron, and protein, and high rates of diabetes, obesity, and infections. Additionally, this population presents many obstacles for nutrition educators including limited resources, child care, transportation, time, language, culture, literacy, health beliefs, and, in some cases, the transient nature of the population. The program attempted to overcome these barriers by incorporating a flexible program format carried out by abuela (Hispanic grandmother) educators using the processes described in the Stage of Change Model. The program was evaluated using a knowledge, skills and behavior pre-test, post-test, and six-month follow-up survey on both the abuela educators as well as the actual class participants. Results of the peer education training sessions suggest that this type of training program can be effective in increasing the knowledge, skills, and behavior of peer educators as well as reduce need for retraining for educators who continuously teach classes. Additionally, the results suggest that this type of program can be effective in changing selected nutrition related knowledge, skills, and behaviors leading to healthy lifestyles for low-income Hispanic mothers of preschool children.

Childhood obesity in a population at high risk for type 2 diabetes

OBJECTIVES

To determine the prevalence of obesity and investigate its association with fasting glucose and insulin among children and adolescents in a population at high risk for type 2 diabetes.

DESIGN

A cross-sectional screening survey involving anthropometry and fasting serum levels of glucose and insulin.

SETTING

A remote aboriginal (Ojibwa-Cree) community in northern Manitoba, Canada.

PARTICIPANTS

All children aged 4 to 19 years in the community were invited to participate, with a response rate of 82% (n = 719).

MAIN OUTCOME MEASURES

Obesity is defined as body mass index exceeding the 85th percentile of the National Center for Health Statistics reference data. The diagnosis of diabetes and impaired fasting glucose is based on the new criteria of the American Diabetes Association.

RESULTS

There is a high prevalence of obesity, with 64% (female) and 60% (male) exceeding the 85th percentile and 40% (female) and 34% (male) exceeding the 95th percentile. Body mass index is a significant predictor of both glucose and insulin in both sexes, independent of age. Obese children are at increased risk of being classified as having diabetes or impaired fasting glucose (odds ratio 5.1, 95% CI 1.51, 17.0).

CONCLUSIONS

The early onset of type 2 diabetes in childhood is increasingly observed in many populations. Childhood obesity is a strong risk factor. Early detection and intervention directed at obesity are potential strategies to avert the long-term consequences of type 2 diabetes.

Black/white differences in relative weight and obesity among girls: the Bogalusa Heart Study

BACKGROUND AND OBJECTIVE

Although black women have a higher prevalence of overweight and obesity than do white women, it is unclear if a similar pattern exists among youths. We therefore examined the development of black/white differences in relative weight and adiposity among 5 to 17-year-old girls.

METHODS

Cross-sectional analyses of 4542 black and 4542 white girls who were examined between 1973 and 1994. Quetelet Index (kg/m(2)), Rohrer Index (kg/m;s(3)), and height-adjusted weight were used as measures of relative weight, and subscapular and triceps skinfolds as measures of adiposity. Breast development was used as an index of sexual maturation.

RESULTS

On average, black girls were 1 to 3 kg heavier than were similarly aged white girls, and before adolescence, they were 2 to 3 cm taller. After adjusting for differences in height, the mean relative weight of black girls was consistently greater than that of white girls only after age 13; furthermore, sexual maturation was a stronger correlate of relative weight among black girls than among white girls. Comparable differences were seen for the subscapular skinfold thickness, but white girls consistently had a thicker mean triceps skinfold than did black girls.

CONCLUSION

Sexual maturation should be considered in comparisons of relative weight and obesity among youths, and as compared with white girls, black girls do not have a higher mean relative weight until adolescence. The use of different indices of overweight and adiposity can lead to contrasting results, with simple comparisons of Quetelet Index tending to overstate the relative weights of taller children.

Growth and overweight of Navajo youth: secular changes from 1955 to 1997

OBJECTIVE

To examine the growth status, prevalence of risk of overweight and of overweight, and secular changes in growth status in Navajo youth from 1955 to 1997.

SUBJECTS

526 (256 males, 270 females) Navajo children 6-12 y of age.

MEASUREMENTS

Stature and mass were measured and the body mass index (BMI) was calculated.

ANALYSIS

All three variables were plotted relative to age- and sex-specific US reference data and the prevalence rates for risk of overweight and of overweight were estimated using the BMI as the criterion. The cut-off for the risk of overweight was the age- and sex-specific 85th and 95th percentiles of NHANES I, while the cut-off for overweight was a BMI>/=95th percentiles. Age-specific sex differences were compared using independent samples t-tests. Secular changes for body size were estimated by comparing age- and sex-specific means for stature, mass, and the BMI in the present study and two previous studies in 1955 and 1989.

RESULTS

No statistically significant differences were observed between sexes within age groups. In both sexes, mean age-specific stature appeared to be relatively stable around the 50th percentile of US reference values. Mean age-specific mass appeared to be relatively stable between the 50th and 90th percentiles of the reference values, while the mean BMI tended to fluctuate about the 85th percentile. Approximately 41% of the Navajo boys and girls 6-12 y of age had BMIs >/=85th percentiles of US reference data. Compared to corresponding data on Navajo youth in 1955 and 1989, the current sample was larger in mass and the BMI. The estimated rate of secular change in mass was about 1.5 kg/decade in younger boys and girls, and about 3 kg/decade in older boys and girls between 1955 and 1997. The estimated rate of secular change in the BMI was about 0.5-1.0 units/decade between 1955 and 1997, while that for stature was about 2 cm/decade between 1955 and 1997.

CONCLUSIONS

The results are consistent with recent findings on the Navajo Health and Nutrition Survey that overweight is a serious public health concern across the lifespan in the Navajo, and that the problem begins in childhood. Furthermore, Navajo children appear to be heavier than about a decade ago. International Journal of Obesity (2000) 24, 211-218

Anthropometric characteristics of Mohawk children aged 6 to 11 years: a population perspective

OBJECTIVE

Recent studies have concluded that Native North American children have higher proportions of overweight and obesity than children from the general North American population. This study presents anthropometric data on a representative sample of children from the Mohawk Nation that can be used for comparison with other Native American populations.

DESIGN

This is a cross-sectional study comparing distributions of anthropometric characteristics of Mohawk children to the corresponding age and gender data from the Second National Health and Nutrition Examination Survey (NHANES II). Weight, height, triceps and subscapular skinfold thickness, and waist and hip circumferences were measured in 527 children.

SUBJECTS/SETTING

All children in grades 1 to 6 (aged 6 to 11 years) in the 3 elementary schools of 2 Mohawk communities in Canada, for whom parental consent was obtained, were enrolled in the present study. There were no exclusion criteria. With a participation rate of 83%, the 527 children enrolled in this study represent an unbiased sample of the population from 2 Mohawk territories.

RESULTS

Compared with children studied in NHANES II, Mohawk children were similar in height and triceps skinfolds but were generally heavier, had thicker subscapular skinfolds, and had greater waist and hip circumferences. These differences were greater in older children. Mohawk children who had extreme-high weight values compared with their population means were heavier than their NHANES II counterparts.

APPLICATIONS/CONCLUSIONS

Results indicated that, on average, Mohawk children seem to be slightly heavier than children in NHANES II. Except for those with extreme overweight values, Mohawk children show less variation of weight and body mass index than children in NHANES II. Finally, overweight Mohawk children seem to be more likely to carry their excess body fat truncally, compared with overweight children from NHANES II. Health practitioners working with Native American populations should be careful when assessing childhood obesity. Simple comparisons of weight or body mass index with NHANES standards may lead to inappropriate risk assessments.

Television viewing, physical activity, and health-related fitness of youth in the Québec Family Study

PURPOSE

To evaluate the relationships among television viewing time (TVTIME), physical activity, and health-related fitness in youth 9-18 years of age from the Québec Family Study.

METHODS

The sample included 423 males and 361 females 9-18 years of age from the greater Québec city area. TVTIME, daily energy expenditure (EE), and moderate to vigorous physical activity (MVPA) were estimated. Four health-related fitness variables were tested: knee extension strength, physical work capacity at 150 beats x min(-1), situps, and sum of skinfolds. The body mass index (BMI) was also included. Relationships were assessed using correlations and analysis of covariance.

RESULTS

Correlations between TVTIME and EE and MVPA were low and not significant, with no pattern by age group and gender. Those between TVTIME and fitness variables were also low and generally not significant, with no pattern by age and gender. Adolescents in the highest and lowest quartiles of TVTIME showed no consistent differences in EE, MVPA, and the four fitness items. Similarly, adolescents in the highest and lowest quartiles of EE, MVPA, and each fitness item did not consistently differ in TVTIME.

CONCLUSIONS

The results indicate that time watching television has only a weak association with indicators of physical activity and health-related fitness in Québec youth. Since the data are from the early 1980s, generalizations to more current samples should be tempered with care.

Psychosocial concerns and weight control behaviors among overweight and nonoverweight Native American adolescents

OBJECTIVE

To compare the psychosocial and weight-related concerns and weight control, eating, and exercise behaviors of overweight and nonoverweight Native American adolescents living on or near reservations.

STUDY DESIGN

A cross-sectional survey assessed psychosocial, health, and weight-specific concerns; disordered eating; and health-promoting behaviors.

STUDY POPULATION

The study population included 11,868 Native American youth in grades 7 through 12.

STATISTICAL ANALYSES PERFORMED

Analyses of variance and chi 2 tests were used to examine associations between weight status and psychosocial and weight-related concerns and behaviors. Stratified analyses were done by gender and by gender and age.

RESULTS

Self-reported weights and heights indicated that 25% of the study population was overweight. Overweight youth were twice as likely to report health concerns as nonoverweight youth. Although a high percentage of nonoverweight youth expressed body- or weight-related concerns and reported engaging in disordered eating behaviors, prevalence rates for these concerns were significantly higher among overweight youth. Overweight youth were also somewhat less likely to engage in health-promoting behaviors. In contrast, differences in global psychosocial concerns were minimal.

APPLICATIONS

Overweight Native American youth were concerned about their weight, but did not appear to have major psychosocial concerns associated with being overweight. Interventions aimed at obesity prevention and overall health promotion are essential, given the high prevalence of obesity and of psychosocial and weight-related concerns and behaviors among the study population as a whole. The challenge is to develop culturally appropriate interventions aimed at the promotion of healthful weight control behaviors that will not lead to negative psychosocial consequences.

Body composition and childhood obesity

Underwater weighing has been the gold standard for the measurement of body composition in humans; however, the two formulas widely used, the Siri and Bronze, were developed using young adult white males. The development of newer techniques in the past 20 years has greatly expanded the accuracy and ease of measuring body composition. These methods have improved the ability to model relationships between body compartments. This article reviews the compartmental models and then critiques the methods available to measure body composition.

Blood lipids, cardiovascular fitness, obesity, and blood pressure: the presence of potential coronary heart disease risk factors in adolescents

OBJECTIVE

To identify and compare the presence of coronary heart disease (CHD) risk factors among 14- and 15-year-old boys and girls.

DESIGN

For this cross-sectional study of 54 subjects, a blood sample taken after subjects fasted was used to determine total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride concentrations. Dietary intake was estimated using a 24-hour recall and a 2-day food record. Height, weight, and skinfold thicknesses were measured to identify obese and severely obese subjects. Cardiovascular fitness, blood pressure, and cigarette use also were measured. TC, HDL-C, LDL-C, fitness, blood pressure, and smoking are modifiable risk factors, for CHD.

SUBJECTS

Adolescents were selected by random sampling from lists of students attending public schools in two central Texas cities. Adolescents who were 14 or 15 years old; were not pregnant; and had no history of high blood pressure, diabetes, or heart disease were eligible to participate.

STATISTICAL METHODS

Data were analyzed using Student's t and chi square tests.

RESULTS

Of the subjects, 25% demonstrated two or more risk factors for CHD. A significantly higher percentage of girls than boys had a TC concentration greater than 5.2 mmol/L. Boys (n=29) had a mean fitness score that indicated a higher level of cardiovascular fitness than girls (n=25); however, the mean score for both groups was below average.

CONCLUSION

Data provide support for increased interventions targeted toward lowering the risk factors for CHD and other chronic diseases in adolescents.

Childhood obesity: pathophysiology and treatment

Childhood obesity is among the most difficult problems which pediatricians treat. It is frequently ignored by the pediatrician or viewed as a form of social deviancy, and blame for treatment failure placed on the patients or their families. The definition of obesity is difficult. Using total body electrical conductivity (TOBEC) technology, total body fat ranges between 12% and 30% of total body weight in normal children and adolescents. This is influenced not only by age, but also by physical fitness. Anthropometry is the easiest way to define obesity. Children whose weight exceeds 120% of that expected for their height are considered overweight. Skinfold thickness and body mass index are indices of obesity that are more difficult to apply to the child. Childhood obesity is associated with obese parents, a higher socioeconomic status, increased parental education, small family size and a sedentary lifestyle. Genetics also clearly plays a role. Studies have demonstrated that obese and non-obese individuals have similar energy intakes implying that obesity results from very small imbalances of energy intake and expenditure. An excess intake of only 418 kJ per day can result in about 4.5 kg of excess weight gain per year. Small differences in basal metabolic rate or the thermic effects of food may also account for the difference in energy balance between the obese and non-obese. In the Prader Willi Syndrome, there appears to be a link between appetite and body fatness. When placed on growth hormone, lean body mass increases, body fat decreases, sometimes to normal, and appetite becomes more normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of race on perception of fat alone and in combination with sugar

Two studies were performed to assess the perception of sugar-fat combinations and fat emulsions in African-American and white subjects. In the first study, African-American children aged 9-15 years were found to prefer higher concentrations of sweetness in liquid dairy products varying in fat content than white children. No significant differences in preference for the four fat levels were found. These data are consistent with a previous study by Desor et al. (2) that suggested African-American youngsters aged 9-15 preferred greater sweetness in water solutions. In a second study, thresholds and preferences for corn oil and butterfat in emulsions were determined for young adults. No significant differences between African-American and white young adults were found.