The prediction of body fatness by BMI and skinfold thicknesses among children and adolescents

BACKGROUND: Although the body mass index (BMI, kg m(-2)) is widely used as a measure of adiposity, it is a measure of excess weight, rather than excess body fat. It has been suggested that skinfold thicknesses be measured among overweight children to confirm the presence of excess adiposity. OBJECTIVE: The present study examined the additional information provided by skinfold thicknesses on body fatness, beyond that conveyed by BMI-for-age, among healthy 5- to 18-years old (n = 1196). METHODS AND PROCEDURES: Total body dual-energy X-ray absorptiometry (DXA) provided estimates of % body fat, and the sum of two skinfolds (triceps and subscapular) was used as an indicator of the overall skinfold thickness. RESULTS: As assessed by the multiple R(2)s and the residuals of various regression models, information on the skinfold sum significantly ( p < 0.001) improved the prediction of body fatness beyond that obtained with BMI-for-age. For example, the use of the skinfold sum, in addition to BMI-for-age, increased the multiple R(2)s for predicting % body fat from 0.81 to 0.90 (boys), and from 0.82 to 0.89 (girls). The use of the skinfold sum also reduced the overall prediction errors (absolute value of the residuals) for % body fat by 20-30%, but these reductions varied substantially by BMI-for-age. Among overweight children, defined by a BMI-for-age >/=95th percentile, the skinfold sum reduced the predication errors for % body fat by only 7-9%. CONCLUSIONS: Although skinfold thicknesses, when used in addition to BMI-for-age, can substantially improve the estimation of body fatness, the improvement among overweight children is small.     

Trends in adiposity in Brazilian 7–10-year-old schoolchildren: evidence for increasing overweight but not obesity between 2002 and 2007

Background: The negative health consequences of childhood overweight/obesity (OW/OB) are well known. Therefore, an accurate monitoring of the OW/OB prevalence is essential. Anthropometry is the most practical and cost-effective method for nutritional status evaluation.

Aim: To describe trends in the nutritional status among 7–10-year-old children by investigating changes in the prevalence of stunting, thinness, overweight, obesity, risk and excess abdominal adiposity, and to study changes in height-for-age, body mass index (BMI) and waist circumference (WC).

Subjects and methods: A school-based sample of 7–10-year-old children participated in two cross-sectional studies in 2002 (n?=?2936) and 2007 (n?=?1232) in Florianopolis, southern Brazil. Prevalence of stunting, risk and excess abdominal adiposity and changes in the distribution of height-for-age, BMI-for-age, WC-for-age z-scores were evaluated. Three BMI-based references were used to define the prevalence of thinness, overweight and obesity.

Results: Between 2002–2007, the prevalence of stunting, thinness, obesity and excess abdominal adiposity remained stable, whereas overweight (including obesity) increased 10–23% in boys and 18–21% in girls, depending on the BMI reference used. The risk of abdominal adiposity increased in boys, but not in girls. No significant change was observed in mean height, BMI, WC-for-age z-scores.

Conclusions: This study identified a potential levelling off in the prevalence of obesity and excess abdominal adiposity, but a continuing increase in the prevalence of overweight.     

Major gene effect on subcutaneous fat distribution in a sedentary population and its response to exercise training: The HERITAGE Family Study

Complex segregation analysis of baseline subcutaneous fat distribution and the change in response to exercise training (post-training minus baseline indices) was performed in a sample of 482 individuals from 99 Caucasian families who participated in the HERITAGE Family Study. The sum of skinfold (SF) thicknesses at eight sites, and the waist and hip circumferences were measured at baseline and after completing a 20-week exercise training program. The trunk-to-extremity ratio (TER) was calculated by dividing the sum of skinfold thicknesses at four trunk sites (subscapular + suprailiac + abdominal + midaxillary) by the sum of skinfold thicknesses at four extremity sites (triceps + biceps + medial calf + thigh). While SF was used to assess total subcutaneous adiposity, TER and the ratio of the waist-to-hip circumferences (WHR) were used to characterize subcutaneous fat distribution. Baseline TER and WHR were age-adjusted and age-SF-adjusted within four sex-by-generation groups. The changes of SF, TER, and WHR in response to training were adjusted for age effects alone and for the effects of age and baseline values. Baseline SF was influenced by a multifactorial component (30%) plus a major effect that may be environmental in origin accounting for 47% of the variance. Baseline TER was influenced by a multifactorial component (18%) and a major codominant gene (q² = 0.10), which accounted for 56% of the variance. The major gene effect was independent of total subcutaneous adiposity. Baseline WHR was regulated by a major codominant gene (q² = 0.15), which accounted for 48% of the variance. However, this major gene effect for baseline WHR should be interpreted with caution, given the estimates of the τ's under the general model. No familial effect was found for the changes in response to training for these subcutaneous adiposity and fat distribution phenotypes. Am. J. Hum. Biol. 12:600–609, 2000. © 2000 Wiley-Liss, Inc.     

The effect of adiposity on the relationship between indicators of maturity in peri-pubertal children

Background: Although the relation between body fatness and maturation has been the subject of much research, somatic maturity as assessed by sex-specific regression equations, has yet to be investigated in a population of overweight and obese children.

Aim: To examine whether adiposity affects the relationship between somatic and skeletal maturity in peri-pubertal children and if increased adiposity is related to earlier maturation.

Subjects and methods: A total of 172 girls and boys (12.8 ± 0.9 years of age) participated in the study. Participants were categorized as normal weight (NW, < 85^th percentile) or overweight/obese (OW/OB, ≥ 85^th percentile) based on body mass index and matched for chronological and skeletal age. Skeletal age was assessed across the radial and ulnar epiphyses using quantitative ultrasound. Somatic maturity was assessed as years from age of peak height velocity (aPHV), estimated using prediction equations. Peripheral adiposity was determined by the sum of two skin-folds.

Results: Years from aPHV was significantly higher (p < 0.001) in OW/OB girls, but not in OW/OB boys. Skeletal age was associated with years from aPHV in NW and OW/OB boys (r = 0.87 vs 0.86, p < 0.001) and girls (r = 0.83 vs 0.72, p < 0.001). Among peri-pubertal youth of similar chronological and skeletal age, OW/OB girls were more somatically mature than their NW peers.

Conclusion: It is concluded that excess peripheral adiposity in girls may affect the estimated somatic maturity, as reflected in years from aPHV.     

Obesity and regional fat distribution in Kenyan populations: Impact of ethnicity and urbanization

Background: Obesity is increasing rapidly in Africa, and may not be associated with the same changes in body composition among different ethnic groups in Africa.

Objective: To assess abdominal visceral and subcutaneous fat thickness, prevalence of obesity, and differences in body composition in rural and urban Kenya.

Subjects and methods: In a cross-sectional study carried out among Luo, Kamba and Maasai in rural and urban Kenya, abdominal visceral and subcutaneous fat thicknesses were measured by ultrasonography. Height and weight, waist, mid-upper arm circumferences, and triceps skinfold thickness were measured. Body mass index (BMI), arm fat area (AFA) and arm muscle area (AMA) were calculated.

Results: Among 1430 individuals (58.3% females) aged 17–68 years, abdominal visceral and subcutaneous fat, BMI, AFA and waist circumference (WC) increased with age, and were highest in the Maasai and in the urban population. AMA was only higher with increasing age among males. The prevalence of overweight (BMI ≥ 25) (39.8% vs. 15.8%) and obesity (BMI ≥ 30) (15.5% vs. 5.1%) was highest in the urban vs. rural population.

Conclusion: Abdominal visceral and subcutaneous fat thickness was higher with urban residency. A high prevalence of overweight and obesity was found. The Maasai had the highest overall fat accumulation.     

Physical activity at 9–12 months and fatness at 2 years of age

Previous research has shown that physical activity in early infancy does not predict later fatness, whereas in preschool children, such a relationship is found. The objective of this study was to investigate whether total energy expenditure (TEE) and behavior in late infancy are related to subcutaneous and total fatness in early childhood. Twenty‐six infants were studied at 9–12 months and followed up at 2 years of age. Anthropometry, body composition, TEE, and behavior were measured in late infancy; skinfold thicknesses and total body fat were measured at 2 years of age. Infant TEE adjusted for fat‐free mass was not related to later fatness. Infant behavior was related to later subcutaneous fatness, but not to total body fatness. Lower levels of infant activity were associated with greater skinfold thicknesses in childhood. Thus, by late infancy, physical activity level is related to subsequent skinfold thickness. Particular aspects of infant behavior appear to be more important than the sum of energy expended on activity. However, the relationship did not extend to total body fat. Am. J. Hum. Biol. 13:384–389, 2001. © 2001 Wiley‐Liss, Inc.     

Relationship of serum cholesterol and truncal body fat distribution among Mexican Americans is accentuated by obesity

The relationship of body fat distribution to serum cholesterol levels was evaluated in a sample of 3,040 Mexican Americans 18–74 years of age from the Hispanic Health and Nutrition Examination Survey (HHANES) conducted from 1982–1984. Fat distribution was determined by the ratio of trunk to extremity skinfold thicknesses, while the sum of skinfold thicknesses was used as an indicator of total body fat. Results of this study indicate that: 1) Mexican Americans are significantly fatter and have a higher trunk/extremity skinfold ratio than U.S. standards; 2) despite their higher level of total body fat and truncal fat, Mexican Americans have lower serum cholesterol levels than U.S. standards; 3) Mexican American males at the same percentile level of fatness or trunk/extremity skinfold ratio have significantly higher serum cholesterols than females, despite the fact that females have higher absolute values of fat and truncal fat than males; 4) among Mexican American males the association between truncal fat distribution and hypercholesteremia increases with level of fatness. In other words, in Mexican American males the association of truncal fat distribution with hypercholesteremia is accentuated by obesity. © 1994 Wiley-Liss, Inc.     

Body fatness in relation to physical activity and selected socioeconomic parameters of adolescents aged 15–17 years in Merida,Yucatan

Background: Increasing rates of overweight and obesity in adolescents are major concerns in many countries, including Mexico.

Objectives: To study anthropometric and body composition characteristics (BCC) and their relations with socioeconomic status (SES), biological history and physical activity (PA) of school-going adolescent boys and girls in the city of Merida, Yucatan, Mexico.

Subjects and methods: In this cross-sectional study, a sample of 321 adolescents (156 boys and 165 girls) aged 15–17 years from public and private schools in Merida, was taken from a study carried out in 2008–2009.

Results: Body mass index had significant correlations to BCC (fat mass and fat-free mass). The rate of stunting was higher in girls (18.20%) than in boys (7.69%). Stunted adolescents had higher body fat (%) than normally growing peers. High rates of overweight (boys 26.28%, girls 24.24%) and obesity (boys 10.26%, girls 6.06%) were recorded. SES (parents’ age, education and occupation; crowding index in the family; household food expenditure), participants’ biological history and PA are related with height and BCC by age and sex.

Conclusion: Adolescents with excess weight (overweight?+?obesity) reported being less physically active. SES and PA were strongly related to growth and body fatness in the studied adolescents.     

Receiver operating characteristic (ROC) curve analysis in 5–10-year-old Bengalee girls from Calcutta,India

Summary.?Objective: The purpose of the present cross-sectional study was to evaluate the sensitivity (SN) and specificity (SP) of body mass index (BMI) and skinfolds thickness: BMI (subcutaneous to overall fat) in detecting excess adiposity in pre-menarcheal Bengalee girls.

Methods: Four hundred and fifty Bengalee girls aged 7.4 ± 1.16 years (mean ± SD; range: 5–10 years) from Calcutta were studied. Anthropometric measures – namely height, weight, circumference of mid upper arm, waist and hip, and skinfold thickness at biceps, triceps, subscapular and suprailiac – were taken from all participants using standard protocols. BMI and the log-transformed sum of four (biceps, triceps, subscapular, suprailiac) skinfolds (log₁₀ SF4) were computed subsequently. Values of log₁₀ SF4 were then converted into seven percentiles category (5th, 10th, 25th, 50th, 75th, 85th and 95th). Excess adiposity was defined as a level of log₁₀ SF4 greater than the internally derived 85th percentile (log₁₀ SF4>85th percentile). SN and SP of each internally derived percentile of BMI and log₁₀ SF4:BMI in detecting excess adiposity were then computed.

Results: SN and SP were 0.49 and 0.94 for the 95th percentile of BMI, and 0.76 and 0.82 for the 95th percentile of log₁₀ SF4:BMI. Moreover, there was a considerable decrease in overall misclassification with the use of log₁₀ SF4:BMI instead of BMI at the 95th percentile (11.2% vs 32%).

Conclusion: Percentiles of BMI in the study had higher SP but low SN in detecting excess adiposity. The use of log₁₀ SF4:BMI, on the other hand, had the merit of increasing SN in a screening programme to evaluate excess adiposity in Bengalee children aged 5–10 years.     

Obesity and upper body fat distribution in Mexican American children from families with a diabetic proband

Upper and centralized body fat distribution is associated with non-insulin dependent diabetes mellitus (NIDDM). Few studies have focused on anthropometric characteristics of preadults from families in which there is a diabetic (NIDDM) proband. This study explores the prevalence of upper and centralized body fatness in Mexican American children from the Diabetes Alert study (1981–1983) in Starr County, Texas. Anthropometric data on 165 males and 224 females 9–19 years include measures of adiposity such as skinfold thicknesses and the body mass index (BMI), a measure of overweight. They show rates of obesity two to three times that of White children of comparable age and sex from National Health Surveys. In comparison with U.S. White subjects, Mexican American adults are shorter, have more adiposity and arm muscle mass and have sitting heights and body breadths at the mean of these dimensions for the U.S. population. Children from Diabetes Alert families show only marginal excess of severe obesity (> 95th percentile of BMI) when compared to the general population of children surveyed in Starr County schools. Girls from these families, but not boys, have excess fatness in the BMI compared to Mexican American children from the Hispanic Health and Nutrition Examination Survey (HHANES); suprailiac skinfold thicknesses are also greater in children of the Diabetes Alert study than in HHANES children. From 1972 through 1982, Mexican American children in South Texas showed an increase in average stature, weight, and the BMI. These data together suggest that excessive obesity exists and may be increasing in children in populations at risk for NIDDM. The prevention of NIDDM in the Mexican American population may be more effective if educational and promotional interventions include the school aged population. © 1993 Wiley-Liss, Inc.     

Estimation of body fat from skinfold thicknesses in middle-aged and older men and women: A multiple component approach

The relationship of skinfold thicknesses and body density to body fatness was assessed, and skinfold prediction equations were developed for the estimation of body fatness determined from measures of body density, total body water, and bone mineral in a sample of 91 males and 116 females aged 34–84 years. For a given skinfold thickness, adjustment for individual deviations in the water and bone mineral fractions of the fat-free body assumed constant by traditional body composition models resulted in absolute reductions in overstimates of body fatness from 4.5 to 1.9% in females and from 2.8 to 1.7% in males for every 15 year increase in age. Percentage fat from density, water, and bone was estimated from skinfold thicknesses with SEEs of 2.9% in males and 3.8% in females. When compared to percentage fat from our multicomponent-derived criterion, percentage fat from body density and a two-component model resulted in individual errors ranging from underestimates of 5.6% fat to overestimates of 14.0% fat. The multicomponent prediction equations presented herein should produce more valid estimates of body composition in middle-aged and older men and women than equations based on two-component models. © 1992 Wiley-Liss, Inc.     

The effects of fatness and fat distribution on respiratory functions

Background: Inverse relationships between respiratory function and indices of obesity and fat distribution have been reported, but it remains unclear which measure of obesity shows the strongest relationship with lung function.

Aim: The study assessed the effect of fatness and fat distribution on respiratory function.

Subjects and methods: A sample of 423 males and 509 females aged 40–50 years were examined in the Silesian Centre for Preventive Medicine, DOLMED, in Wroc?aw in 1995. The strength of influence of height, body mass index (BMI), wait-to-hip ratio (WHR) and abdominal and subscapular skinfolds upon forced vital capacity (FVC) and forced expiratory volume in a 1-s expiration (FEV₁) was assessed by multiple regression analysis.

Results: In males, FVC was strongly positively associated with height and BMI, but negatively associated with subscapular and abdominal skinfolds, WHR, and smoking. FEV₁ showed a positive relationship with height, BMI and WHR. In females, both FVC and FEV₁ showed significant positive associations with height, negative ones with subscapular skinfold, and no association with either WHR or abdominal skinfold. In males, respiratory function is affected to a similar extent by fat in the abdominal region and by fatness of the chest. In females, fatness of the thorax has the strongest relationship with respiratory function.

Conclusion: Fatness tends to impair respiratory function in both sexes but these effects show a different pattern in males and females. In males, respiratory functions are significantly, and to a similar extant, affected by fatness in the abdominal region, both subcutaneous and visceral, and by fatness on the chest. In females, it is primarily subcutaneous fat on the upper thorax that affects respiratory functions, while visceral and subcutaneous abdominal fatness play little or no role.     

Association of FTO and IRX3 genetic variants to obesity risk in north India

Abstract

Objective: Validation of body adiposity index (BAI) in a paediatrics sample; and to develop, if necessary, a valid BAI for paediatrics (i.e. BAI_p).

Methods: A total of 1615 children (52% boys) aged 5–12 years underwent anthropometry. Their body composition was assessed using a foot-to-foot bioimpedance. The validity of BAI?=?(Hip circumference/Height^1.5)???18 was tested by combining correlation and agreement statistics. Then, the sample was split into two sub-samples for the construction of BAI_p. A regression was used to compute the prediction equation for BAI_p-based percentage of body fat (%BF).

Results: The initial BAI over-estimated the %BF of children by 49% (29.6?±?4.2% versus 19.8?±?6.8%; p?<?0.0001). The original methodology led to a BAI_p?=?(Hip circumference/Height^0.8) ? 38 in children. When compared to BAI, BAI_p showed both better correlation (r?=?0.57; p?<?0.01 versus r?=?0.74; p?<?0.0001) and agreement (ICC?=?0.34; [95% CI?=??0.19–0.65] versus ICC?=?0.83; [95% CI?=?0.81–0.84]). However, there were some systematic biases between the two values of %BF as exemplified by the large 95% limit of agreement [?9.1%; 8.8%] obtained.

Conclusion: BAI over-estimates the %BF in children. In contrast, BAI_p appears as a new index for children’s body fatness, with acceptable accuracy. In its current form, this index is valid only for large-scale studies.     

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.     

Blood pressure and adiposity: A comparative study of socioeconomically diverse groups of Andhra Pradesh,India

The effect of adiposity on blood pressures, systolic (SBP), and diastolic (DBP), was examined in a sample of 1119 individuals (456 males, 663 females), 18–75 years, from socioeconomically diverse populations from Southern Andhra Pradesh, India. The populations were graded into four socioeconomic groups, group I–seminomadic Yerukalas, group II–hard working scheduled caste Mala and the Muslims, group III–land owning agricultural castes Reddy and Balija, and group IV–sedentary urban dwelling castes such as Brahmins, Vyshyas, and Marwadis. There was a trend of increase in mean blood pressures and the frequency of hypertensives (SBP ≥160 and/or DBP ≥95) with increasing age in all groups, and the increase was more distinct from group I to group IV. Mean values of body mass index (BMI: weight/height²) and body fat (SF4: sum of biceps, triceps, subscapular, and suprailiac skinfolds) also showed an increasing trend from group I to group IV. A somewhat opposite trend was evident in two indices of fat distribution, centripetal fat ratio (CFR: ratio of subscapular to the sum of subscapular and triceps skin fold thicknesses) and the relative fat pattern index (RFPI: ratio of subscapular skinfold thickness to the sum of subscapular and suprailiac skinfold thicknesses). Step-wise regression analysis indicated that while one or the other adiposity measures along with one of the age terms significantly contributed to SBP variation among males in the affluent groups III and IV, neither any adiposity measure nor age explain the variation in group I, and only body fat, not age, in group II. A qualitatively similar pattern was observed in females, except that BMI explained a significant amount of variation in SBP in group I, and only age and not any of the adiposity measures, in group IV. Besides age, BMI and fat pattern indices accounted for a significant amount of variation in DBP, while RFPI explained a significant amount of variation in group IV. The amount of variation in SBP explained by the age and adiposity measures increased from the traditional to urbanized groups in males (2.4% to 24.8%) and females (11.4% to 43.6%). A similar trend was observed in case of DBP in both males (0.2% to 15.4%) and females (7.6% to 21.8%). Analysis of covariance of the pooled sample suggested that each of five categorical variables—physical activity, smoking, income, food habit, and group membership—independently explained a significant amount of residual variation in SBP of males, while only food habit and social status did so in females. DBP variation, however, was significantly accounted for by only three of the five (excluding food habit and smoking) categorical variables in males and by none in females. The effect of categorical variables on the residual variation in SBP becomes increasingly significant from the traditional to the urbanized groups in males, while this trend is not consistent in females. Am. J. Hum. Biol. 10:5–21, 1998. © 1998 Wiley-Liss, Inc.     

Fatness and fat distribution in Mexican-American children and youths from the Hispanic health and nutrition examination survey

Mexican-American children are shorter but relatively heavier than non-Hispanic white children. The excess relative weight is probably due to increased fat rather than lean body mass and, more specifically, to increased fat deposition on the upper trunk sites. The objective of this paper is to describe the level of fatness and fat distribution in a large, representative sample of Mexican- American children and adolescents from the recently completed Hispanic Health and Nutrition Examination Survey (HHANES). As expected, Mexican-American children are generally fatter than white children measured in previous national surveys (National Health and Nutrition Examination Survey [NHANES] II, Health Examination Survey [HES]). Differences are particularly evident for trunk skinfold thicknesses and generally increase with age. Indices of fat distribution clearly show a centralized, upper body adiposity pattern among Mexican-Americans, a cause for concern since greater fat deposition on the trunk has been associated with increased risk of certain chronic disease.     

Urban–rural contrasts in the growth status of school children in Oaxaca,Mexico

Objectives:?The growth status of school children resident in an urban colonia and in a rural indigenous community in Oaxaca, southern Mexico, was considered in the context of two objectives, current status and the magnitude of urban–rural differences over a span of about 30 years. Both communities were initially surveyed in 1968 and 1972.

Materials and methods:?Height, body mass, segment lengths, skeletal breadths, limb circumferences, and subcutaneous fatness were taken on 361 rural (177 boys, 184 girls) and 339 urban (173 boys, 166 girls) school children, aged 6–13 years. Additional variables were derived.

Results:?Height and body mass were significantly greater in urban compared with rural children. Sitting height, estimated leg length and skeletal breadths on the trunk were also larger in urban than in rural school children, but only the difference in skeletal breadths was significant after age and body size were statistically controlled. Urban and rural children did not consistently differ in skeletal breadths on the extremities and limb circumferences. Subcutaneous fatness was more variable. After controlling for age and body size, rural girls had thicker skinfolds. The magnitude of the urban–rural difference in boys in 2000 was greater for body mass, BMI and triceps skinfold, and reduced for height, sitting height, leg length, and arm and estimated arm muscle circumferences compared with 1970. The magnitude of the urban–rural difference in girls was greater in 2000 than 30 years earlier for body mass, height, sitting height, leg length and BMI. Urban–rural differences for arm and arm muscle circumferences and the triceps skinfold were slightly smaller over the interval.

Conclusions:?Children resident in an urban colonia were taller and heavier than children resident in a rural indigenous community. After controlling for age and body size, urban–rural differences in skeletal breadths and limb circumferences were reduced or eliminated, but skinfold thicknesses were greater in rural girls. The magnitude of urban–rural differences in body size has decreased over approximately 30 years in boys, but has increased in girls.     

Socioeconomic status and body size among women in Honduran Miskito communities

Background: This study investigates evidence of the nutrition transition among women in Miskito communities on the northeastern coast of Honduras.

Aim: The hypothesis that socioeconomic status (SES) is positively associated with body size and fatness is tested; and dietary and physical activity patterns are examined among SES groups.

Subjects and methods: An anthropometric survey was conducted with 200 non-pregnant women following standard procedures. Dietary intake and physical activity data were collected using 24-hour recall methods. Women were categorized into three SES groups (high, medium and low) based on economic and social attributes. Differences in anthropometric measures, diet and physical activity among SES groups were analysed.

Results: More than 70% (n = 142) of women in the sample were overweight or obese. Mean height, weight, skin-fold thicknesses, arm and calf circumferences, percentage body fat and upper-arm fat area were significantly greater among high SES women than low SES women. Women with high SES had lower rates of physical activity and higher rates of obesity, perceived food sufficiency, meat consumption, milk/dairy intake and general dietary diversity.

Conclusion: High SES women were significantly fatter than low SES women; and variation observed among groups is likely related to different patterns of dietary intake and physical activity.     

The relation of BMI and skinfold thicknesses to risk factors among young and middle-aged adults: The Bogalusa Heart Study

Objective: Although adverse levels of cardiovascular disease risk factors are related to skinfold thicknesses and BMI among adults, the relative strengths of these associations are unknown. We examine whether the triceps and subscapular skinfold thicknesses are more strongly related to adult levels of lipids, fasting insulin and blood pressure than BMI.

Design and subjects: Cross-sectional (n = 3318) and longitudinal (n = 1593) analyses of 18- to 44-year-olds examined in the Bogalusa Heart Study from 1983 to 2002. Principal components analysis was used to derive a summary index of the six examined risk factors (triglycerides, low- and high-density lipoprotein cholesterol, insulin, and systolic and diastolic blood pressures).

Results: The magnitudes of the differences were generally small, but all comparisons indicated that BMI was at least as strongly related to adverse risk factor levels as was the sum of subscapular and triceps skinfold thicknesses (SF sum). For example, adjusted cross-sectional associations with the risk factor summary were r = 0.55 (BMI) and r = 0.49 (SF sum), p < 0.001 for difference between correlations. Similar differences were seen in longitudinal analyses, with changes in the risk factor summary being more strongly associated with changes in BMI (r = 0.50) than with changes in the SF sum (r = 0.38).

Conclusion: BMI appears to be at least as accurate as skinfold thicknesses in identifying metabolic risk among adults. The advantages of BMI should be considered in the design and interpretation of clinical and epidemiologic studies.     

Effect of husbands' education on fatness of wives

The aim of the study was to examine the relationship between social position of females achieved by marriage and level of fatness and relative fat distribution. The data of 588 healthy, occupationally active, married women, age 21–62 years, with 12 years of education (completed secondary school) were used. The body mass index (BMI, kg/m² ), triceps and subscapular skinfold thicknesses, and summed skinfold thicknesses were used as indicators of fatness. The waist–hip ratio, the waist–thigh ratio, and waist, hip, and thigh circumferences were used as indicators of fat distribution. According to the educational level of husbands, women were grouped as 1) moving up the social scale (spouse with complete university education), 2) stable (equal level of education), and 3) moving down the social scale (spouse who never passed beyond the level of basic vocational school, i.e., skilled and unskilled manual workers). The two opposite groups were analyzed, i.e., moving up and moving down. Women with secondary schooling who married up were consistently leaner than women who married down. A similar pattern was observed for fat distribution. Women marrying down had more abdominal body fat compared to women marrying up. Am. J. Hum. Biol. 15:1–7, 2003. © 2002 Wiley‐Liss, Inc.