Fat In Children Research Articles

Estimates of Body Fat in Children by Hologic QDR‐2000 and QDR‐4500A Dual‐Energy X‐ray Absorptiometers Compared With Deuterium Dilution

We evaluated the accuracy with which the Hologic QDR-4500A and QDR-2000 densitometers measure fat mass (FM) in 95 children. FM was derived from total body water measured by deuterium dilution (DD) in all children, by QDR-4500A in 50, and by QDR-2000 in 45 children. Compared with DD, both instruments underestimated FM (QDR-4500A: 3.35 +/- 2.5 kg, P < 0.0001; QDR-2000: 1.05 +/- 1.5 kg, P < 0.0001). Both absorptiometers showed magnitude biases relative to DD (QDR-4500: r = +0.70, P < 0.001; QDR-2000: r = -0.51, P < 0.001). We conclude that neither densitometer is equivalent to DD for estimation of children's FM. The QDR-4500A's current calibration seems to provide an even greater underestimate of FM than the QDR-2000.

Relationships Between Physical Inactivity And Activity In Preschoolers

The prevalence of overweight and obesity in young children is increasing rapidly. The age at which lifestyle and environment become important factors in the development of this and other CVD risk factors has not been established. Previously reported data suggest that in children as young as 3 yrs. significant negative relationships exist between a child's body fatness and physical activity (PA)levels and the mother's BMI and PA. PURPOSE To evaluate the predictors of physical inactivity (PI) in preschool children. METHODS PA and PI was assessed with triaxial accelerometers (Stayhealthy, Inc.). A parent was instructed on how to place the monitor on the child upon awaking in the morning and to remove the monitor before sleep. Vector magnitude(VM), expressed as cts/min, was calculated from a unit's three accelerometers and taken as a measure of PA; <10cts/min was taken as a measure of PI. PA and PI was assessed during waking hours for three days(2 weekdays and 1 weekend day). Measures of body composition were determined using DXA, including percent body fat (PBF), lean (LBM), and fat mass (FM). Height(ht) and weight(wt) were measured and BMI was calculated. Spearman correlation and then stepwise linear regression (SLR) analyses were performed to determine which factors were associated with PI. RESULTS 286 children completed the assessments. Mean age of the children was 4.6 +/− .25 yrs. (range 3.7 to 5.3); 17% of the children were black and 56% were males. Activity cts/min (Actvm/min) was negatively correlated with PI (r=−.38, p<0.0001) and PBF (r=−.19, p<0.002) and positvely correlated with LBM (r=.17, p<0.006). In SLR analyses, we found that Actvm/min was the only significant predictor of PI (p<0.01). However, Actvm/min(p<0.005), ht(p<0.0001), wt(p<0.0001), and gender(p<0.0001) were significant predictors of PBF. CONCLUSIONS These data suggest that in young children PI and PBF is negatively related to the intesnity of PA throughout the day and that ht, wt and gender are significantly related with PBF. Lifestyle and environment may play a role in overweight and obesity in preschool aged children.

A supply-demand model of fetal energy sufficiency predicts lipid profiles in male but not female Filipino adolescents.

To test the hypothesis that the balance between fetal nutritional demand and maternal nutritional supply during pregnancy will predict lipid profiles in offspring measured in adolescence. A total of 296 male and 307 female Filipino offspring (aged 14-16 y) and mothers enrolled in a longitudinal birth cohort study (begun in 1983-84) had lipid profiles measured. Data on maternal height (as a proxy for offspring growth potential and thus fetal nutritional demand) and third trimester maternal arm fat area (as a proxy for maternal supply) were used to create four groups hypothesized to reflect a gradient of fetal energy sufficiency. As fetal energy sufficiency increased among males, there was a decrease in total cholesterol (TC) (P<0.05 for trend), low-density lipoprotein cholesterol (LDL-C), and the ratios of TC/HDL-C cholesterol and LDL-C/HDL-C (all P<0.001), while HDL-C increased (P<0.05). Similar associations were identified when lipid levels were modeled as dichotomous 'high-risk' cut-points used in cardiovascular disease prevention in adolescents. These relationships were stronger, or only present, among offspring of mothers in the lower half of the third trimester energy intake distribution, and were independent of the child's current adiposity, dietary energy and fat intake, maturity, household income, and birth weight. In females, the supply-demand model did not predict any lipid outcome or clinical risk criteria. Our findings in males support the hypothesis that the balance between fetal nutritional demand and maternal nutritional supply has implications for future lipid profiles. The lack of significant associations in females adds to mounting evidence for sex differences in lipid metabolism programming, and may reflect sex differences in fetal nutritional demand. The National Science Foundation, the Mellon Foundation, the Nestle Foundation, and the Emory University Internationalization Program.

Food insecurity is associated with dietary intake and body size of Korean children from low-income families in urban areas.

This study examined household food insecurity of urban low-income families in Korea and the associations of the food insecurity with children's dietary intake and body size. Cross-sectional study. Low-income neighborhoods in large cities. Included 370 children aged 4-12 y, who had all records on dietary intake and anthropometry as well as household food insecurity measures. Using the 10-item Radimer/Cornell Scale, 62.7% of the households showed some degree of food insecurity (8.6% for food insecure for family, 28.4% for food insecure for adults and 25.7% for child hunger households). Food insecurity was linearly and negatively associated with household economic conditions as well as the caretaker's use of nutrition knowledge. There were also significant associations of food insecurity with the children's dietary intakes, indicating the largest amount of nutrients for the children from the household food insecure, followed by those from the food secure, adult food insecure and child hunger groups. The household food insecure children were fatter than the food secure children. The fatter condition of the former children appeared to be related to more frequent intakes of low-quality foods. This study reports curvilinear associations between the status of household food insecurity and children's food intakes and fatness. This work was funded by a grant of the 2001 Korea Health Promotion Research Program, the Ministry of Health & Welfare, Republic of Korea.

Which Metric of Relative Weight Best Captures Body Fatness in Children?

To evaluate the relative merits of BMI (kilograms per meter squared) and age- and gender-adjusted BMI, age- and gender-specific z score of BMI, and age- and gender-specific percentiles of BMI as surrogate measures of body fatness among a sample of youth. The sample comprised 596 children and adolescents 5 to 18.7 years old and was 40% male and 55% white. Height and weight were measured by trained research staff. DXA was used to determine body fat mass. BMI, age- and gender-specific percentile of BMI, and age- and gender-specific z scores of BMI were computed, and these metrics were compared with measured body fatness. The BMI values in the sample ranged from 12.9 to 55.0 kg/m(2), with a mean of 24.9 kg/m(2). The Spearman correlations with percentage body fat were similar for all of the BMI metrics (r = 0.82 to 0.88). Linear regression models with age- and gender-specific percentiles of BMI explained significantly less of the variance (65%) than models with log-transformed BMI (81%) or age- and gender-specific z scores of BMI (75% to 79%). z scores were the most accurate at classifying children who were overfat (sensitivity = 0.84, specificity = 0.96 for z score > or = 1). However, using a BMI > or = 85th percentile or a BMI > or = 20 kg/m(2) was also accurate at classifying youth. The BMI metrics had similar correlations with body fatness, but age- and gender-specific percentiles of BMI were the least accurate proxy measure of body fatness. However, a BMI z score > or = 1, BMI percentile > or = 85, and BMI> or = 20 kg/m(2) are all useful for identifying children who may be overfat.

Error in timing in regression with observed longitudinal measurements.

We consider regression analysis of a disease outcome in relation to longitudinal data which are observations from a random effects model. The covariate variables of interest are the values of the underlying trajectory at some time points, which may be fixed or subject-specific. Because the underlying random coefficients are unknown, the covariates to the primary model are generally unobserved. In addition, measurements are often not observed at the time points of interest. A motivating example to our model is the effects of age at adiposity rebound and the associated body mass index on the risk of adult obesity. The adiposity rebound is a time point at which the trajectory of a child's body fatness declines to a minimum. This general error in timing problem may be applied to an analysis when time-dependent marker variables follow a polynomial model in which the effect of a local maximum or minimum point may be of interest. It can be seen that directly applying estimated covariates, possibly obtained from estimated time points, may lead to bias. Estimation procedures based on expected estimating equations, regression calibration and simulation extrapolation are applied to this problem.

Effects of gender, apolipoprotein E phenotype and cholesterol‐lowering by plant stanol esters in children: The STRIP study

Aim: To evaluate the effects of gender, apolipoprotein E phenotype and cholesterol absorption and synthesis (estimated as serum plant sterol and cholesterol precursor sterol concentrations) on the cholesterol‐lowering effect of plant stanol esters in children. Methods: Eighty‐one healthy, normocholesterolaemic 6‐y‐old children (45 boys) were recruited from the Special Turku Coronary Risk Factor Intervention Project (STRIP), a randomized prospective trial aiming at atherosclerosis prevention in childhood. This placebo‐controlled, double‐blind, cross‐over study comprised two 3‐mo study periods and a 6‐wk wash‐out period. During the study periods, 20 g of the children's daily dietary fat intake was replaced with plant stanol ester margarine or control margarine. Results: In boys, plant stanol esters reduced serum total and low‐density lipoprotein cholesterol concentrations by 6% (0.09 to 0.42mmol/L) and 9% (0.09 to 0.36mmol/L), respectively (p &gt; 0.01 for both). In girls, the decreases in concentrations were 4% (0.03 to 0.38 mmol/L) and 6% (0.02 to 0.32 mmol/1) (p &gt; 0.05 for both). The response rate did not differ between the genders. Serum total and low‐density lipoprotein cholesterol concentrations decreased by 6% and 8% (p &gt; 0.01 for both), respectively, in both children with the apolipoprotein E 3/4 or 4/4 (apoE4+) phenotype and the apolipoprotein E 2/3 or 3/3 (apoE4—) phenotype. Cholesterol absorption decreased both in the apoE4+ children and in the apoE4— children, but cholesterol synthesis consistently increased in the apoE4+ children only. Conclusion: Plant stanol esters reduce serum cholesterol concentration in healthy children irrespective of their gender or apoE4 phenotype.

Dietary Patterns and Nutrient Intakes of 7-Year-Old Children Taking Part in an Atherosclerosis Prevention Project in Finland

Objective To evaluate the dietary patterns of 7-year-old children participating in an atherosclerosis prevention project and the relationship of those dietary patterns to nutrient intakes and serum cholesterol values. Design In the randomized, prospective Special Turku Coronary Risk Factor Intervention Project (STRIP) 1,062 children were randomly assigned to an intervention group (n=540; low-saturated fat, low-cholesterol diet) or to a control group (n=522; unrestricted diet) at 7 months of age. Subjects/settings The intervention families received, at 6-month intervals, individualized counseling that focused on the known environmental atherosclerosis risk factors and aimed at reducing children's saturated fat and cholesterol intake. Nutrition counseling was targeted at the child but, because of the young age of the children, was given to the parents. When children were 7 years old, food and nutrient intakes of 307 intervention and 323 control children were studied using 4-day food records. Statistical analyses performed K-means cluster analysis was used to classify children into 4 groups on the basis of similarity of food intake. Differences in nutrient intakes and serum lipid concentrations between children in the 4 food intake clusters were evaluated using Tukey's multiple comparison test. Results Intervention children dominated the bread, skim milk, and margarine cluster and the cereals, rice, and pasta cluster whereas the 1.5%-fat milk and butter cluster included mainly control children. Saturated fat intake was nearest to the recommendations, that is 11.7% and 11.9% of energy, in the bread, skim milk, and margarine cluster and the cereals, rice, and pasta cluster, respectively. Children in the bread, skim milk, and margarine cluster had 20% to 27% higher fiber intakes ( P<.001) whereas children in the sugar and sweets cluster had markedly higher sugar intakes than children in other clusters ( P<.001). Serum cholesterol concentrations were lower in those clusters with high dietary ratios of polyunsaturated to saturated fat. Conclusion Detailed and repeated dietary counseling of parents, starting when children are aged 7 months, that aims at decreasing children's exposure to known nutrition risk factors for coronary heart disease modifies children's food patterns and nutrient intakes toward expected values. J Am Diet Assoc. 2002; 102:518–524.

Growth of visceral fat, subcutaneous abdominal fat, and total body fat in children.

To examine the patterns of growth of visceral fat, subcutaneous abdominal fat, and total body fat over a 3- to 5-year period in white and African American children. Children (mean age: 8.1 +/- 1.6 years at baseline) were recruited from Birmingham, Alabama, and those with three or more repeated annual measurements were included in the analysis (N = 138 children and 601 observations). Abdominal adipose tissue (visceral and subcutaneous) was measured using computed tomography. Total body fat and lean tissue mass were measured by DXA. Random growth curve modeling was performed to estimate growth rates of the different body fat compartments. Visceral fat and total body fat both exhibited significant growth effects before and after adjusting for subcutaneous abdominal fat and lean tissue mass, respectively, and for gender, race, and baseline age (5.2 +/- 2.2 cm(2)/yr and 1.9 +/- 0.8 kg/yr, respectively). After adjusting for total body fat, the growth of subcutaneous abdominal fat was not significant. Whites showed a higher visceral fat growth than did African Americans (difference: 1.9 +/- 0.8 cm(2)/yr), but there was no ethnic difference for growth of subcutaneous abdominal fat or total body fat. There were no gender differences found for any of the growth rates. Growth of visceral fat remained significant after adjusting for growth of subcutaneous abdominal fat, implying that the acquisition of the two abdominal fat compartments may involve different physiologic mechanisms. In contrast, growth of subcutaneous abdominal fat was explained by growth in total body fat, suggesting that subcutaneous fat may not be preferentially deposited in the abdominal area during this phase of growth. Finally, significantly higher growth of visceral fat in white compared with African American children is consistent with cross-sectional findings.

Plant stanol ester margarine lowers serum total and low-density lipoprotein cholesterol concentrations of healthy children: The STRIP project

Objective: To investigate cholesterol-lowering efficacy and safety of plant stanol ester margarine in healthy 6-year-old children already consuming a low-saturated-fat, low-cholesterol diet.Study design: Eighty-one intervention children from the STRIP project, a randomized prospective trial aimed at reducing exposure of young children to the known environmental atherosclerosis risk factors, were recruited to this double-blind crossover study at 6 years of age. In randomized order the families were advised to replace daily 20 g of the child's dietary fat intake with plant stanol ester margarine or control margarine for 3 months. The washout period lasted 6 weeks. Statistical analysis was performed according to intention-to-treat principle with analysis of variance for crossover design.Results: The mean daily plant stanol ester margarine consumption was 18.2 g (1.5 g plant stanol). The well-tolerated plant stanol ester margarine reduced serum total and low-density lipoprotein cholesterol concentrations by 5.4% and 7.5%, respectively (P = .0001 for both). The serum high-density lipoprotein cholesterol and triglyceride concentrations and α-tocopherol to low-density lipoprotein cholesterol ratio remained unchanged. The serum β-carotene to low-density lipoprotein cholesterol ratio decreased by 19% (P = .003).Conclusion: Plant stanol ester margarine significantly diminishes serum total and low-density lipoprotein cholesterol concentration without adverse clinical effects in healthy children who already consume a low-saturated-fat, low-cholesterol diet but decreases the serum β-carotene to low-density lipoprotein cholesterol ratio.

Serum Leptin Levels Correlate with Growth Hormone Secretion and Body Fat in Children

Serum Leptin Levels Correlate with Growth Hormone Secretion and Body Fat in Children

Socio-economic factors and body composition

This study supplies further data to the question of influence of social background in body development. There are a great number of studies concerning the influence of socio-economic factors on growth. On the other hand, there are very few investigations into the factors of body composition though these factors give more information about the developmental stage of the children's skeleton, muscle and fat mass than any absolute measurement. The social status was established on the basis of the parents' occupation, educational level, the per capita income, per capita room-quota and sibling number. Beyond these factors the effects of maternal age at childbirth and birth order were investigated in a sample of 3553 boys and 3371 girls aged between 7–14. Body composition was studied by a two-component model. Results of body composition have shown that children living under better social circumstances are not only heavier, because they have more developed skeleton and musculature, but have more body fat mass too. The excess of their body fat mass is caused in part by the unaltered habits of nutrition, in part by sedentary life style. These results stress the necessity for a more efficient somatic and environmental education.

Parental smoking and risk factors for cardiovascular disease in 10- to 12-year-old children.

Smokers have multiple adverse health-related behaviors and an increased risk of cardiovascular disease. We examined whether health behaviors in parents who smoke may influence children's health behaviors. Cross-sectional data from 10- to 12-year-olds (n = 800) entering a trial of health promotion programs. Smoking in children was independently associated with maternal (odds ratio 2.1, confidence interval 1.2, 3.8) and paternal smoking (odds ratio 2.1, confidence interval 1.2, 3.7) and was less likely in girls (odds ratio 0.4, confidence interval 0.2, 0.6). Maternal smoking and paternal smoking were additive predictors in children of lower physical activity (P = .0013 for mothers; P = .0476 for fathers) and more television watching (P = .0335 for mothers; P = .0241 for fathers). Children's fat intake was significantly greater if either parent smoked. Children's body mass index (P = .0183) and waist-to-hip ratio (P = .0009) were significantly greater if mothers smoked. Poor health behaviors associated with smoking in parents, particularly mothers, are likely to influence children's long-term risk of having lifestyle diseases. The results may also explain some of the apparent effects attributed to passive smoking in families.

Leptin levels and body fatness in children: effects of gender, ethnicity, and sexual development.

Leptin, a hormone secreted by adipocytes, is elevated in blood of obese adults. It is unknown whether the concentration is affected by gender, ethnicity, age, or stage of sexual maturation in children. We measured serum leptin levels in 183 children and 27 young adults using a double-antibody ELISA assay. Body fat mass (FM) and percent body fatness (%Fat) were determined by dual-energy x-ray absorptiometry. Correlations for serum leptin with FM, %Fat, and a body mass index were examined. Analyses of covariance were used to determine the effects of gender, ethnicity, and sexual maturation (Tanner stage). We found strong positive correlations (r = 0.56-0.88, p < 0.001) for serum leptin with body mass index. %Fat, and FM, which were gender-dependent (p < 0.001), but unaffected by ethnicity. At each Tanner stage, female subjects had higher serum leptin than male subjects (p < 0.001), and this difference remained significant (p < 0.001) when leptin was normalized for FM. For each gender, the mean leptin/FM ratios were relatively invariant during sexual maturation and no differences were observed between the oldest children (Tanner stage 5) and the young adults. The observation that female subjects have higher mean serum leptin and leptin/FM levels than male subjects at prepubertal ages may suggest that there are gender differences in leptin synthesis, clearance rates, bioactivity, and/or leptin transport.

The utility of body mass index as a measure of body fatness in children and adolescents: differences by race and gender.

To evaluate whether body mass index (BMI) is a representative equivalent measure of body fatness independent of age, race, gender, sexual maturation, and distribution of fat in children and adolescents. Cross-sectional study of 192 healthy subjects (100 boys and 92 girls, 103 white and 89 black) age 7 to 17 years. Methods. Height and weight were measured in the standard fashion, and BMI (kg/m) was calculated from these values. Fat mass and percent body fat were determined using dual-energy x-ray absorptiometry. Sexual maturation was evaluated by physical assessment. Distribution of fat was determined by the waist:hip ratio. There were no significant differences by gender and ethnic group for any of the demographic or anthropometric variables, except waist:hip ratio, which was higher in white compared with black boys. BMI was significantly and positively correlated with age, stage of maturation, and all of the anthropometric variables in each race-sex group. The correlation of maturation stage with BMI was stronger than the correlation between age and BMI. A multiple regression analysis showed that BMI, gender, race, sexual maturation, and distribution of fat were all significant independent correlates of the percent body fat (multiple R = .77). The percent body fat-BMI relationship was dependent on the stage of sexual maturation, gender (for an equivalent BMI, girls have greater amounts of body fat than boys), race (for equivalent BMI, whites have higher body fat than blacks), and waist:hip ratio (for equivalent BMI, those with central obesity have greater body fatness than those with peripheral obesity). BMI is not an equivalent measure of the percent body fat for each race-sex group. When BMI is used as a measure of body fatness in a research or clinical setting, particularly when comparisons are made across race and gender, it may be important to consider the maturation stage, race, gender, and distribution of body fat in the interpretation of the results.

Relationship of Diet-Health Attitudes and Nutrition Knowledge of Household Meal Planners to the Fat and Fiber Intakes of Meal Planners and Preschoolers

The relationship of household meal planners’ diet-health attitudes and nutrition knowledge to their fat and fiber intakes and to the intakes of 2- to 5-year-old children in the households was examined using data from the 1989–91 Continuing Survey of Food Intake by Individuals and Diet Health Knowledge Survey (CSFII/DHKS). Selected households (n = 478) provided 24-hour diet recalls and the households’ main meal planners responded to the DHKS. Meal planner attitude variables were defined according to the Health Belief Model and selected CSFII/DHKS questions served as proxy measures. The relationship of meal planners’ attitudes and knowledge to meal planners’ and children's fat and fiber consumption at home and in the total diet was analyzed using multiple regression. Several diet-health attitude variables were significantly related to meal planners’ fat and fiber intakes and relationships were similar for foods eaten at home and for foods eaten in the total diet. Knowledge was significantly related to meal planners’ and children's home fat intake (p < .05) but the relationships failed to reach statistical significance for the total diets. Meal planners’ taste concerns differed significantly in their relationship to meal planners’ and children's fiber consumption (p < .05). Results indicate that parents’ diet-health attitudes are more influential in their diets than in the diets of preschoolers. Findings also suggest that taste and practical food concerns are significant barriers to healthy eating among younger adults and that general nutrition knowledge may not be as helpful in making healthy food choices outside the home as it may be in the home setting.

Relationship of Socioeconomic, Demographic, and Behavioral Variables to Changes in Children's Fat Intakes Between 1989-91 and 1994

LEARNING OUTCOME: To better understand factors associated with the decline in fat intakes by children 2-17 years of age between 1989-91 and 1994.The U.S. Department of Agriculture's Continuing Survey of Food Intakes by Individuals (CSFII) 1989-91 and 1994 data indicate that fat intakes by children 2-17 years of age declined from 34 percent of calories in 1989-91 to 33 percent of calories in 1994. This study investigated whether this decline was associated with specific socioeconomic, demographic, or behavioral characteristics. The sample included 3,025 children 2-17 years of age who provided one 24-hour recall in either CSFII 1989-91 or CSFII 1994. One child was randomly selected from each survey household to avoid household clustering effects. Multiple regression analysis was used to assess the effects of selected independent variables on children's fat intakes. These variables included socioeconomic status (SES) as defined by household income and educational level of the household meal planner, region and urbanization level of residence, age, sex, and race of the child, food stamp program participation, school food consumption, meal planner employment status, season and day of week of reported intake and survey time period (1989-91 vs. 1994). Interaction terms assessing differences in the effects of SES between the two time periods were also included. The interaction of time with higher SES (household income above 185 percent of the Federal poverty level and meal planner with at least some college education) was significant (p<.05) and negative, indicating that between 1989-91 and 1994 higher SES was associated with a significant decline in children's fat intakes. Other factors significantly associated with lower fat intakes were being of a race other than black or white and living in the Northeast region of the United States as opposed to the South. School food consumption was significantly associated with higher fat intakes. Results suggest that fat intakes by lower SES children are slower to approach Dietary Guidelines recommendations than those of higher SES children. Nutrition interventions directed toward these children may be needed.

Fat Preferences and Fat Consumption of 3- to 5-year-old Children are Related to Parental Adiposity

Objective To examine differences in preferences for high-fat foods, dietary fat intake, anthropometric measurements, and parental body mass index (BMI) among 3- to 5-year-old children. Design Children's fat intake was measured using 30-hour weighed food intake data from a standard menu. Children's fat preferences were assessed using a subset of foods from the standard menu. We obtained parents’ BMI scores and children's anthropometric measurements including weight-for-stature, triceps, and subscapular skinfolds. Subjects Participants were children 3 to 5 years of age (n=18, 10 girls and 8 boys; mean [±standard deviation] age=52±1.9 months) who were without food allergies, food sensitivities, or chronic illness, and the childrens’ parents (18 mothers and 16 fathers). Statistical analyses performed Correlational analyses and maximum likelihood contingency tables were used to examine children's fat preferences and fat intake, children's anthropometric measurements, and BMI scores of parents. Results Although all children were offered the same daily menu, children's dietary fat intakes ranged from 25% to 42%. Children indicating strong preferences for high-fat foods had high total fat intakes ( r=.54, P<.05; χ 2=3.96, df=1, P<.05). Children's fat preferences were also related to their triceps skinfold measurements ( r=.61; P<.01). Finally, those children with the strongest preferences for high-fat foods ( r=.75, P<.01; χ 2=10.68, df=1, P<.05) and the highest total fat intakes ( r=.67, P<.01;χ 2=5.28, df=1, P<.05) had heavier parents than did children with low scores. Conclusions Offering children a nutritionally adequate diet is necessary but may not be sufficient to ensure dietary quality; children's food preferences are influential determinants of macronutrient intake. The association of children's fat preferences and intake with parental adiposity suggests that dietary influences may mediate familial patterns of adiposity. J Am Diet Assoc. 1995; 95:759-764.

Cluster Analysis of Levels of Body Fatness in Children

The purpose of this study was to examine, using cluster analysis, the levels of body fatness as defined in the current national programs for children and youth fitness. A total of 1,056 examinees were drawn randomly from the published data of the National Children and Youth Fitness Study II, with 525 boys and 531 girls, ages 6 to 9 years. Their triceps and medial calf skinfold measures were used for the cluster analysis, including both the kth nearest-neighbor and the Ward's minimum variance procedures. Although multimodal clusters were found at four age groups according to the kth nearest-neighbor procedure, the Ward procedure and plotting of these clusters did not support their existence. It was concluded that the levels of body fatness reported in the current national children and youth fitness programs were arbitrarily defined.

Assessment of obesity in children

Obesity is usually defined on the basis of body composition measurements. Body composition can be assessed using elaborate methods or anthropometry. The choice of methods depends on the practical conditions of the study. Elaborate methods give accurate information, but they usually have high cost and high technical difficulty, and while considered precise, they still have limitations. They are often based on hypotheses established in adults, and usually in normal weight subjects. Their applicability to obese children is sometimes questionable. Anthropometric measurements are used either directly or as indices or in regression equations. As it is weakly correlated with height and highly correlated with body fat, the Weight/Height 2 Quetelet or Body Mass Index (BMI) is used as an index of adiposity. As opposed to traditional growth charts, the BMI charts simultaneously take weight, height and age into account. The BMI curve reflects the real changes of the child's body shape and fatness during growth. Early in life, it can be used as an indicator of later development. Measurement of weight and height should be augmented by skinfolds. The triceps skinfold is usually recommended and widely used, but trunk skinfolds, such as the subscapular, are better on many counts (e.g. association with body fat pattern or with risk factors, response to nutritional interventions etc.). Measurements can be expressed as a percentage of standard or as Z-score (SD unit). Both methods have limitations: the former does not take the changes of distribution with age into account, the latter does not take variations in prevalence of obesity with age into account. It is suggested here to use the latter method based on a selected healthy population or on a population presenting a low prevalence of obesity. Selecting a limited number of methodologies would improve inter-study comparisons and consequently research on obesity.