Hispanic and Asian pubertal girls have higher android/gynoid fat ratio than whites

Associations of eating speed with fat distribution and body shape vary in different age groups and obesity status

Background

Eating speed has been reported to be associated with energy intake, body weight, waist circumference (WC), and total body fat. However, no study has explored the association between eating speed and body fat distribution, especially its difference among different age or body mass index (BMI) groups.

Methods

4770 participants aged 18–80 years were recruited from the baseline survey of the Lanxi Cohort Study. They were categorized into three groups according to meal duration. Linear regression analyses were performed among all participants and separately by age group and obesity status to evaluate the associations of WC and total and regional fat mass percentages (FM%) with eating speed.

Results

After adjusting for confounding factors, eating slowly was significantly related to lower WC, lower total, trunk, and android FM%, lower android-to-gynoid fat mass ratio, and higher leg and gynoid FM%. After stratification by age or obesity status, the associations were especially prominent among participants aged 18–44 years or those with BMI < 24 kg/m². No significant trends were found for participants aged 65–80 years or those who were overweight/obese.

Conclusions

Eating slowly is closely related with better fat distribution among Chinese adults, especially for those aged 18–44 years and those with BMI < 24 kg/m². If confirmed prospectively, it might be a potential efficient approach to improve fat distribution.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12986-022-00698-w.

Official Position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry-part II (clinical aspects): interpretation, reporting, and special situations

OBJECTIVE

To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice.

MATERIALS AND METHODS

This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals.

CONCLUSION

This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.

The onset of pubertal development and actigraphy-assessed sleep during middle childhood: Racial, gender, and genetic effects

OBJECTIVE

This study (1) examined pubertal development in relation to actigraphy-assessed sleep in twin children, and tested whether associations differed by child race and gender, (2) modeled genetic and environmental influences on pubertal development and sleep indicators, and (3) examined genetic and environmental influences on the covariation of puberty and sleep.

DESIGN

The classic twin design was used to examine genetic and environmental contributions to puberty and sleep and their associations.

SETTING

Data were collected from community-dwelling urban and rural families of twins in the southwestern U.S.

PARTICIPANTS

The racially and socioeconomically diverse sample included 596 twin children (M_age = 8.41, SD = 0.69; 51.7% female; 66.3% white; 33.7% Hispanic; 170 monozygotic, 236 same-sex dizygotic, 188 opposite-sex dizygotic).

MEASUREMENTS

Pubertal development was assessed via parent report. Children wore actigraph watches for 7 nights (M = 6.81, SD = 0.67) to capture sleep duration, efficiency, midpoint, onset latency, and duration variability.

RESULTS

In contrast to extant literature with older youth, more advanced pubertal development was associated with longer sleep durations in Hispanic and white girls and higher sleep efficiency in white girls, though Hispanic girls demonstrated later sleep midpoints. Pubertal development was moderately heritable and there was a genetic influence on the covariance between puberty and sleep indicators.

CONCLUSIONS

This was the first study to examine the genetic and environmental influences on the covariation between puberty and sleep, and found genetic underpinnings between pubertal development and actigraphy-assessed sleep duration and efficiency, though sleep and puberty were almost entirely independent in twins at this age.

Ethnic differences in adiposity and diabetes risk - insights from genetic studies

Type 2 diabetes is more common in non-Europeans and starts at a younger age and at lower BMI cut-offs. This review discusses the insights from genetic studies about pathophysiological mechanisms which determine risk of disease with a focus on the role of adiposity and body fat distribution in ethnic disparity in risk of type 2 diabetes. During the past decade, genome-wide association studies (GWAS) have identified more than 400 genetic variants associated with the risk of type 2 diabetes. The Eurocentric nature of these genetic studies has made them less effective in identifying mechanisms that make non-Europeans more susceptible to higher risk of disease. One possible mechanism suggested by epidemiological studies is the role of ethnic difference in body fat distribution. Using genetic variants associated with an ability to store extra fat in a safe place, which is subcutaneous adipose tissue, we discuss how different ethnic groups could be genetically less susceptible to type 2 diabetes by developing a more favourable fat distribution.

Abdominal Adiposity and Total Body Fat as Predictors of Cardiometabolic Health in Children and Adolescents With Obesity

Objective: We aimed to assess the role of adipose tissue distribution in cardiometabolic risk (in particular insulin sensitivity) in a population of children and adolescents with obesity. Methods: In this cross-sectional study, participants were 479 children and adolescents with obesity (322 boys and 157 girls) aged 3 to 18 years attending the Children's Hospital at Zhejiang University School of Medicine (Hangzhou, China). Clinical assessments included anthropometry, body composition (DXA scans), carotid artery ultrasounds, and OGTT. Insulin sensitivity was assessed using the Matsuda index. Participants were stratified into groups by sex and pubertal stage. Key predictors were DXA-derived android-to-gynoid-fat ratio (A/G) and total body fat percentage (TBF%). Results: Irrespective of sex and pubertal stage, there was a strong association between increasing A/G (i.e., greater abdominal adiposity) and lower insulin sensitivity. In multivariable models, every 0.1 increase in A/G was associated with a reduction in insulin sensitivity in prepubertal boys [-29% (95% CI -36%, -20%); p < 0.0001], pubertal boys [-13% (95% CI -21%, -6%); p = 0.001], and pubertal girls [-16% (95% CI -24%, -6%); p = 0.002]. In contrast, TBF% was not associated with insulin sensitivity when A/G was adjusted for, irrespective of pubertal stage or sex. In addition, every 0.1 increase in A/G was associated with increased likelihood of dyslipidemia in prepubertal boys [adjusted odds ratio (aOR) 1.62 (95% CI 1.05, 2.49)], impaired glucose tolerance in pubertal boys [aOR 1.64 (95% CI 1.07, 2.51)] and pubertal girls [aOR 1.81 (95% CI 1.10, 2.98)], and odds of NAFLD in both prepubertal [aOR 2.57 (95% CI 1.56, 4.21)] and pubertal [aOR 1.69 (95% CI 1.18, 2.40)] boys. In contrast, higher TBF% was only associated with higher fasting insulin and ALT in pubertal boys, being also predictive of NAFLD in this group [aOR 1.15 per percentage point (95% CI 1.06, 1.26)], but was not associated with the likelihood of other cardiometabolic outcomes assessed in any group. Conclusions: A/G is a much stronger independent predictor of cardiometabolic risk factors in children and adolescents with obesity in China, particularly glucose metabolism.

Individual mesh size for open anterior inguinal hernia repair: an anthropometric study in Turkish male patients

PURPOSE

To conduct a study to determine the measurements of the inguinal region in male patients with inguinal hernias to reveal the proper mesh size for each patient.

METHODS

In this prospective study, the anthropometric measurements were obtained from 100 consecutive adult male patients with unilateral primary inguinal hernias. First, the distance between the pubic tubercle and the medial border of the deep inguinal ring was measured (x). Second, the distance between the inner edge of the inguinal ligament and the uppermost level of the internal oblique aponeurosis at the midpoint of the inguinal ligament corresponding to the Hesselbach triangle was measured (y). Individual mesh sizes were calculated according to the original recommendations for mesh overlap.

RESULTS

The mean x value was 41.6 mm (22-55 mm), the mean y value was 45.2 mm (30-68 mm). The mean dimensions of the mesh were 126.6 mm × 65.2 mm. The largest mesh was 140 mm × 88 mm, and the smallest one was 107 mm × 62 mm. The mean mesh area was 8320 mm². It was larger than the index mesh area recommended by the Lichtenstein Hernia Institute in 45 patients and smaller in 55 patients.

CONCLUSIONS

The intraoperative measurements for ideal mesh size in Lichtenstein repair of inguinal hernias may present somewhat different mesh dimensions in many patients. Individualization of mesh size may be of importance in surgical outcomes.

Racial and Ethnic Differences in Anthropometric Measures as Risk Factors for Diabetes

OBJECTIVE

The study objective was to examine the impact of race/ethnicity on associations between anthropometric measures and diabetes risk.

RESEARCH DESIGN AND METHODS

A total of 136,112 postmenopausal women aged 50-79 years participating in the Women's Health Initiative without baseline cancer or diabetes were followed for 14.6 years. BMI, waist circumference (WC), and waist-to-hip ratio (WHR) were measured in all participants, and a subset of 9,695 had assessment of whole-body fat mass, whole-body percent fat, trunk fat mass, and leg fat mass by DXA. Incident diabetes was assessed via self-report. Multivariate Cox proportional hazards regression models were used to assess associations between anthropometrics and diabetes incidence.

RESULTS

During follow-up, 18,706 cases of incident diabetes were identified. BMI, WC, and WHR were all positively associated with diabetes risk in each racial and ethnic group. WC had the strongest association with risk of diabetes across all racial and ethnic groups. Compared with non-Hispanic whites, associations with WC were weaker in black women (P < 0.0001) and stronger in Asian women (P < 0.0001). Among women with DXA determinations, black women had a weaker association with whole-body fat (P = 0.02) but a stronger association with trunk-to-leg fat ratio (P = 0.03) compared with white women.

CONCLUSIONS

In postmenopausal women across all racial/ethnic groups, WC was a better predictor of diabetes risk, especially for Asian women. Better anthropometric measures that reflect trunk-to-leg fat ratio may improve diabetes risk assessment for black women.

Childhood and adolescent phenol and phthalate exposure and the age of menarche in Latina girls

BACKGROUND

The age of menarche has been associated with metabolic and cardiovascular disease, as well as cancer risk. The decline in menarcheal age over the past century may be partially attributable to increased exposure to endocrine disrupting chemicals (EDCs).

METHODS

We assessed the influence of 26 phenol and phthalate biomarkers on the timing of menarche in a longitudinal cohort of Chilean girls. These EDCs were quantified in urine collected prior to the onset of breast development (Tanner 1; B1), and during adolescence (Tanner 4; B4). Multivariable accelerated failure time (AFT) models were used to analyze associations between biomarker concentrations and the age of menarche adjusting for body mass index (BMI) Z-score and maternal education, accounting for within-subject correlation.

RESULTS

Several biomarkers were significantly associated with the age at menarche; however, these associations were dependent on the timing of biomarker assessment. A log(ng/ml) increase in B1 concentrations of di(2-ethylhexyl) phthalate biomarkers was associated with later menarche (hazard ratio (HR): 0.77; 95% CI: 0.60, 0.98), whereas higher B1 concentrations of 2,5-dichlorophenol and benzophenone-3 were associated with earlier menarche (HR: 1.13; 95% CI: 1.01, 1.27; HR: 1.17; 95% CI: 1.06, 1.29, respectively). Elevated B4 concentrations of monomethyl phthalate were similarly associated with earlier menarche (HR: 1.30; 95% CI: 1.10, 1.53). The impact of monoethyl phthalate and triclosan concentrations on pubertal timing were significantly modified by BMI Z-score. Higher monoethyl phthalate and triclosan concentrations were associated with earlier menarche among overweight or obese girls, but not among those that were normal weight.

CONCLUSIONS

This study identifies modulation of sexual maturation by specific EDC biomarkers in Latina girls.

Comparisons of Waist Circumference Measurements at Five Different Anatomical Sites in Chinese Children

This study compared the waist circumference (WC) measurements of Chinese children at different sites to determine the relationship between WC measurements and body fat. WC was measured at five sites in 255 subjects aged 9-19 years: immediately below the lowest rib (WC1), at the narrowest waist (WC2), the midpoint between the lowest rib and the iliac crest (WC3), 1 cm above the umbilicus (WC4), and immediately above the iliac crest (WC5). Body fat mass (FM), body fat percentage (% BF), body fat mass in the trunk (FM in the trunk), and fat percentage in the trunk (% BF in the trunk) were determined by dual-energy X-ray absorptiometry. The WCs were then compared through ANOVA with repeated measurement. The relationship of WC of each site with FM, % BF, FM in the trunk, and % BF in the trunk was examined through partial correlation. The WCs exhibited the following pattern: WC2 < WC1 < WC3 < WC4 < WC5 (p < 0.001) in males and WC2 < WC1 < WC4, WC3 < WC5 (p < 0.001) in females. The measured WCs were strongly correlated with FM, % BF, FM in the trunk, and % BF in the trunk. The WC measurements at five commonly used sites among Chinese children are different from one another. Results indicate that standardizing the anatomic point for the WC measurements is necessary.

Energetics and the immune system: Trade-offs associated with non-acute levels of CRP in adolescent Gambian girls

Background and objectives: The human immune system is an ever-changing composition of innumerable cells and proteins, continually ready to respond to pathogens or insults. The cost of maintaining this state of immunological readiness is rarely considered. In this paper we aim to discern a cost to non-acute immune function by investigating how low levels of C-reactive protein (CRP) relate to other energetic demands and resources in adolescent Gambian girls.

Methodology: Data from a longitudinal study of 66 adolescent girls was used to test hypotheses around investment in immune function. Non-acute (under 2 mg/L) CRP was used as an index of immune function. Predictor variables include linear height velocity, adiposity, leptin, and measures of energy balance.

Results: Non-acute log CRP was positively associated with adiposity (β = 0.16, P < 0.001, R² = 0.17) and levels of the adipokine leptin (β = 1.17, P = 0.006, R² = 0.09). CRP was also negatively associated with increased investment in growth, as measured by height velocity (β = −0.58, P < 0.001, R² = 0.13) and lean mass deposition β = −0.42, P = 0.005, R² = 0.08). Relationships between adiposity and growth explained some, but not all, of this association. We do not find that CRP was related to energy balance.

Conclusions and implications: These data support a hypothesis that investment in non-acute immune function is facultative, and sensitive to energetic resources and demands. We also find support for an adaptive association between the immune system and adipose tissue.

The Interplay Between Sex, Ethnicity, and Adipose Tissue Characteristics

The obesity epidemic in the USA affects disproportionately women and the ethnic minorities. On the other hand, female sex is traditionally associated with a favorable fat distribution preferentially in the subcutaneous depots of the lower body and with improved endocrine and metabolic function of the adipose tissue. However, these data are derived from predominantly non-Hispanic white populations. This review discusses fat distribution patterns in women of diverse ethnic backgrounds, together with data on the release of adipokines from adipose tissue in these populations. Very little information is available on how the metabolic function of the adipocyte differs depending on ethnicity. Thus, it becomes clear that future clinical and translational research should explicitly discuss and take into account the sex and ethnic background of the populations studied.

Endogenous thrombin potential in polycystic ovary syndrome: the association to body mass index, insulin resistance, and inflammation

OBJECTIVES

The objective of this study is to investigate plasma endogenous thrombin generation in four different phenotypes of polycystic ovary syndrome (PCOS) defined by Body Mass Index (BMI) and insulin resistance (IR). PCOS is diagnosed according to the Rotterdam criteria.

DESIGN

Multicenter cross-sectional study.

SETTING

Two major University Hospitals in the Capital region of Denmark.

PATIENTS

Hundred forty-eight European women with PCOS were consecutively recruited during April 2010-February 2012. Clinical examination, blood sampling, and DEXA scan were performed.

MAIN OUTCOME MEASURES

Endogenous thrombin potential (ETP).

RESULTS

PCOS women with phenotype BMI > 25 + IR have increased potential of thrombin generation. ETP is associated with total body fat mass, IR, and CRP.

CONCLUSIONS

Obese and insulin resistant women with PCOS have elevated level of ETP corresponding to increased risk of CVD. ETP is related to well-known CVD risk factors in PCOS but not in general to the Rotterdam criteria.

Association of regional body fat with metabolic risks in Chinese women

OBJECTIVE

To investigate the association of regional fat depots with metabolic risk factors in Chinese women.

DESIGN

Total and regional fat depots including android fat and gynoid fat were measured by dual-energy X-ray absorptiometry. Central fat distribution was defined as android:gynoid fat ratio. Metabolic risk factors were defined as elevated TAG, reduced HDL-cholesterol, elevated blood pressure and elevated fasting plasma glucose. Logistic regression analyses were performed to examine the associations of regional fat depots with metabolic risk factors. The odds ratios of metabolic risks were further calculated according to tertiles of android fat and gynoid fat.

SETTING

Participants were recruited from a community-based cross-sectional study. Face-to-face questionnaires, anthropometric and dual-energy X-ray absorptiometry measures were conducted.

SUBJECTS

Chinese women (n 609) aged 18-79 years.

RESULTS

Android fat and android:gynoid fat ratio were associated with significantly increased odds (OR = 1·4-3·7; P < 0·01) for almost all risk factors, whereas gynoid fat was independently associated with significantly decreased odds (OR = 0·3-0·6; P < 0·01). The inverse associations of gynoid fat with metabolic risk factors remained after adjusting for android fat. Even if their android fat level was in high, women in the highest tertile of gynoid fat had lower odds of having at least two metabolic risk factors compared with women in the lowest gynoid fat tertile (P for trend < 0·01).

CONCLUSIONS

There were opposite associations of android and gynoid fat with metabolic risks in Chinese women. Gynoid fat rather than android fat might be a more important inclusion in metabolic disease risk evaluation in female Asians.

Metabolic, cardiovascular and anthropometric differences between prepubertal girls and boys

OBJECTIVE

We aimed to assess possible differences in insulin sensitivity and other metabolic, anthropometric and cardiovascular parameters between boys and girls prior to puberty.

METHODS

We studied 85 healthy prepubertal children (33 girls and 52 boys) aged 8.7 ± 1.9 years (range 4.0-11.9 years), born 38-40 weeks gestation, and of birth weight appropriate-for-gestational-age. Insulin sensitivity was measured using frequently sampled intravenous glucose tests and Bergman's minimal model. Other clinical assessments included anthropometric measures, fasting lipid and hormonal profiles, body composition from whole-body dual-energy X-ray absorptiometry and 24-h ambulatory blood pressure monitoring.

RESULTS

Prepubertal girls and boys were of similar parent-adjusted height SDS (P = 0.26), but girls had considerably more body fat (P < 0.0001), less fat-free mass (P = 0.0002) and greater abdominal adiposity (P < 0.0001). These differences in body composition were independent of adrenal androgens. Insulin sensitivity was 18% lower in girls (11.0 vs 13.4 × 10(-4) /min (mU/l); P = 0.028), but this difference disappeared with adjustment for adiposity and DHEAS concentrations. There were, however, some apparent sex differences in cardiovascular parameters, with girls displaying increased heart rate and reduced blood pressure dipping. Girls also had higher triglyceride concentrations (+23%; P = 0.036).

CONCLUSION

There are a number of anthropometric, metabolic and cardiovascular differences between sexes prior to the appearance of external signs of puberty. Although differences in insulin sensitivity were eliminated when adiposity and DHEAS concentrations were accounted for, there were independent differences in body composition and cardiovascular parameters. Thus, gender, adrenarche and adiposity should be accounted for in studies examining metabolic and cardiovascular outcomes prior to puberty.

Central fat accumulation associated with metabolic risks beyond total fat in normal BMI Chinese adults

OBJECTIVE

To investigate the association of central fat with metabolic risks in normal BMI Chinese people.

METHODS

Normal BMI subjects (18.5 ≤ BMI < 24, n = 520) aged 18-82 years were included. Blood pressure, triglycerides, high-density lipoprotein cholesterol and fasting plasma glucose were collected as metabolic risk factors. Dual-energy X-ray absorptiometry was used to measure total and central fat. Central fat was indicated as percent trunk fat (%TF) and android/gynoid fat ratio. Multiple adjusted regression models were applied to investigate the association of total and central fat with metabolic risk factors. The assessment values of these fat measures were further compared by receiver-operating characteristic (ROC) curves.

RESULTS

Both total and central fat were correlated with metabolic risk factors. After adjusting for BMI, the significant association of percent body fat (%BF) with metabolic risks diminished, whereas %TF and android/gynoid fat ratio were still correlated. When BMI was replaced with %BF in the models, the results remained unchanged. ROC analysis showed the areas under the curve (AUCs) of total and central fat for at least two metabolic risk factors were comparable in men. However, in women, the AUCs of %TF and android/gynoid fat ratio were significantly greater than those of BMI, %BF and waist circumference.

CONCLUSIONS

Central fat accumulation had a stronger association with metabolic risks than total fat in normal BMI Chinese adults, particularly in women. Central fat had more important implications in assessing 'metabolically obese' individuals among normal BMI subjects.

Fat mass localization alters fuel oxidation during exercise in normal weight women

PURPOSE

Abdominal and lower body fat mass tissues exhibit particular metabolic profiles at rest and during exercise. However, data are missing in normal weight women during exercise. The purpose of this study was to investigate the effect of low (LA/LB) and high (HA/LB) abdominal to lower body (A/LB) fat mass ratio on metabolic and hormonal responses during exercise in premenopausal normal weight women.

METHODS

After preliminary testing (V˙O2max and body composition assessment), substrate oxidation (RER, lipid, and carbohydrate oxidation rates), metabolic response (glycerol, free fatty acids, and glucose), and hormonal response (insulin, growth hormone, atrial natriuretic peptide, adrenaline, and noradrenaline) were determined during exercise (45 min at 65% of V˙O2max) in 21 premenopausal normal weight women (10 HA/LB women vs 11 LA/LB women).

RESULTS

Waist circumference was significantly higher in HA/LB women compared with LA/LB women (P < 0.01). No difference in other anthropometric characteristics, V˙O2max, and resting blood values was observed between the two groups. LA/LB subjects exhibited greater lipid oxidation rates compared with HA/LB women during exercise (P < 0.01). This occurred with lower plasma insulin (P < 0.05) and glucose (P < 0.05) concentrations and higher plasma free fatty acids (P < 0.05), glycerol (P < 0.05), growth hormone (P < 0.05), and atrial natriuretic peptide levels (P < 0.01) during exercise in the LA/LB group compared with the HA/LB group.

CONCLUSIONS

The present study demonstrated that LA/LB women exhibited an increase in whole-body lipid mobilization and use during exercise compared with HA/LB counterparts. This greater reliance on lipid as fuel metabolism during exercise could be explained by substrate availability and metabolic and hormonal responses. It appeared that LA/LB women exhibited greater metabolic flexibility during an exercise bout of 45 min at 65% of V˙O2max on cycle ergometer.

Polycystic ovary syndrome and low-grade inflammation with special reference to YKL-40

OBJECTIVE

To evaluate the plasma level of YKL-40 in a Danish polycystic ovary syndrome (PCOS) population and to investigate whether YKL-40 is associated with CVD risk factors such as waist circumference, body mass index (BMI), insulin resistance (IR), fasting glucose, fasting insulin, blood lipids and CRP.

DESIGN

Cross-sectional study.

SETTING

Gynecological clinics at three Danish University Hospitals.

PATIENTS

One hundred seventy-one premenopausal women with PCOS recruited consecutively from April 2010 to February 2012. PCOS was diagnosed according to the Rotterdam criteria.

MAIN OUTCOME MEASURES

Plasma level of YKL-40 in four phenotypes of PCOS defined by BMI and IR.

RESULTS

No statistically significant difference was observed in the plasma level of YKL-40 across the four BMI/IR-phenotypes. Positive associations were observed between YKL-40 and BMI, total and free testosterone, triglycerides, and CRP. Total and free testosterone were independent predictors of YKL-40.

CONCLUSION

YKL-40, the marker of low-grade inflammation is not increased in women with PCOS.

Update on body composition and bone density in children with Prader-Willi syndrome

AIM

To compare body composition in children with Prader-Willi syndrome (PWS) not naïve to growth hormone (GH) with obese and lean controls.

METHODS

Participants included 12 children with PWS, 12 children with obesity (body fat percentage >95th percentile for age and sex) and 12 lean children (body fat percentage <85th percentile for age and sex) matched by age and height. Fat mass, lean mass, bone mineral content (BMC), bone mineral density (BMD) and BMD z-score for total body, hips and lumbar spine were obtained through dual X-ray absorptiometry.

RESULTS

PWS had higher fat percentage in the legs (p = 0.04) but similar leg fat mass (p = 1.00) compared to obese. PWS exhibited lower lean mass in the body (p = 0.04) and legs (p = 0.02) than obese, but similar to lean (p = 1.00 and p = 0.89, respectively). PWS had lower hip BMC (p < 0.01), BMD (p < 0.01) and BMD z-score (p < 0.01) compared to obese but similar to lean. No other differences were found between PWS and obese (p > 0.05 for all).

CONCLUSIONS

Children with PWS not naïve to GH present differences in fat and lean mass distribution compared to obese controls. BMC and BMD appear unaffected by PWS, except at the hips.

The Official Positions of the International Society for Clinical Densitometry: body composition analysis reporting

Dual-energy x-ray absorptiometry (DXA) measurements of body composition increasingly are used in the evaluation of clinical disorders, but there has been little guidance on how to effectively report these measures. Uniformity in reporting of body composition measures will aid in the diagnosis of clinical disorders such as obesity, sarcopenia, and lipodystrophy. At the 2013 International Society for Clinical Densitometry Position Development Conference on body composition, the reporting section recommended that all DXA body composition reports should contain parameters of body mass index, bone mineral density, BMC, total mass, total lean mass, total fat mass, and percent fat mass. The inclusion of additional measures of adiposity and lean mass are optional, including visceral adipose tissue, appendicular lean mass index, android/gynoid percent fat ratio, trunk to leg fat mass ratio, lean mass index, and fat mass index. Within the United States, we recommend the use of the National Health and Nutrition Examination Survey 1999-2004 body composition dataset as an age-, gender-, and race-specific reference and to calibrate BMC in 4-compartment models. Z-scores and percentiles of body composition measures may be useful for clinical interpretation if methods are used to adjust for non-normality. In particular, DXA body composition measures may be useful for risk-stratification of obese and sarcopenic patients, but there needs to be validation of thresholds to define obesity and sarcopenia. To summarize, these guidelines provide evidence-based standards for the reporting and clinical application of DXA-based measures of body composition.

Birth order progressively affects childhood height

BACKGROUND

There is evidence suggesting that first-born children and adults are anthropometrically different to later-borns. Thus, we aimed to assess whether birth order was associated with changes in growth and metabolism in childhood.

METHODS

We studied 312 healthy prepubertal children: 157 first-borns and 155 later-borns. Children were aged 3-10 years, born 37-41 weeks gestation, and of birth weight appropriate-for-gestational-age. Clinical assessments included measurement of children's height, weight, fasting lipid and hormonal profiles and DEXA-derived body composition.

RESULTS

First-borns were taller than later-borns (P < 0·0001), even when adjusted for parents' heights (0·31 vs 0·03 SDS; P = 0·001). There was an incremental height decrease with increasing birth order, so that first-borns were taller than second-borns (P < 0·001), who were in turn taller than third-borns (P = 0·007). Further, among sibling pairs both height SDS (P = 0·009) and adjusted height SDS (P < 0·0001) were lower in second- vs first-born children. Consistent with differences in stature, first- (P = 0·043) and second-borns (P = 0·003) had higher IGF-I concentrations than third-borns. Both first- (P < 0·001) and second-borns (P = 0·004) also had reduced abdominal adiposity (lower android fat to gynoid fat ratio) when compared with third-borns. Other parameters of adiposity and blood lipids were unaffected by birth order.

CONCLUSIONS

First-borns were taller than later-born children, with an incremental height reduction from first to third birth order. These differences were present after correction for genetic height, and associated to some extent with alterations in plasma IGF-I. Our findings strengthen the evidence that birth order is associated with phenotypic changes in childhood.

Ratio of trunk to leg volume as a new body shape metric for diabetes and mortality

BACKGROUND

Body shape is a known risk factor for diabetes and mortality, but the methods estimating body shape, BMI and waist circumference are crude. We determined whether a novel body shape measure, trunk to leg volume ratio, was independently associated with diabetes and mortality.

METHODS

Data from the National Health and Nutritional Examination Survey 1999-2004, a study representative of the US population, were used to generate dual-energy X-ray absorptiometry-derived trunk to leg volume ratio and determine its associations to diabetes, metabolic covariates, and mortality by BMI category, gender, and race/ethnicity group.

RESULTS

The prevalence of pre-diabetes and diabetes increased with age, BMI, triglycerides, blood pressure, and decreased HDL level. After adjusting for covariates, the corresponding fourth to first quartile trunk to leg volume ratio odds ratios (OR) were 6.8 (95% confidence interval [CI], 4.9-9.6) for diabetes, 3.9 (95% CI, 3.0-5.2) for high triglycerides, 1.8 (95% CI, 1.6-2.1) for high blood pressure, 3.0 (95% CI, 2.4-3.8) for low HDL, 3.6 (95% CI, 2.8-4.7) for metabolic syndrome, and 1.76 (95% CI, 1.20-2.60) for mortality. Additionally, trunk to leg volume ratio was the strongest independent measure associated with diabetes (P<0.001), even after adjusting for BMI and waist circumference. Even among those with normal BMI, those in the highest quartile of trunk to leg volume ratio had a higher likelihood of death (5.5%) than those in the lowest quartile (0.2%). Overall, trunk to leg volume ratio is driven by competing mechanisms of changing adiposity and lean mass.

CONCLUSIONS

A high ratio of trunk to leg volume showed a strong association to diabetes and mortality that was independent of total and regional fat distributions. This novel body shape measure provides additional information regarding central adiposity and appendicular wasting to better stratify individuals at risk for diabetes and mortality, even among those with normal BMI.

Total and regional body volumes derived from dual-energy X-ray absorptiometry output

Total body volume is an important health metric used to measure body density, shape, and multicompartmental body composition but is currently only available through underwater weighing or air displacement plethysmography (ADP). The objective of this investigation was to derive an accurate body volume from dual-energy X-ray absorptiometry (DXA)-reported measures for advanced body composition models. Volunteers received a whole body DXA scan and an ADP measure at baseline (N = 25) and 6 mo (N = 22). Baseline measures were used to calibrate body volume from the reported DXA masses of fat, lean, and bone mineral content. A second population (N = 385) from the National Health and Nutrition Examination Survey was used to estimate the test-retest precision of regional (arms, legs, head, and trunk) and total body volumes. Overall, we found that DXA-volume was highly correlated to ADP-volume (R² = 0.99). The 6-mo change in total DXA-volume was highly correlated to change in ADP-volume (R² = 0.98). The root mean square percent coefficient of variation precision of DXA-volume measures ranged from 1.1% (total) to 3.2% (head). We conclude that the DXA-volume method can measure body volume accurately and precisely, can be used in body composition models, could be an independent health indicator, and is useful as a prospective or retrospective biomarker of body composition.

Pre-pubertal children born post-term have reduced insulin sensitivity and other markers of the metabolic syndrome

BACKGROUND

There are no data on the metabolic consequences of post-term birth (≥42 weeks gestation). We hypothesized that post-term birth would adversely affect insulin sensitivity, as well as other metabolic parameters and body composition in childhood.

METHODS

77 healthy pre-pubertal children, born appropriate-for-gestational-age were studied in Auckland, New Zealand: 36 born post-term (18 boys) and 41 (27 boys) born at term (38-40 weeks gestation). Primary outcome was insulin sensitivity measured using intravenous glucose tolerance tests and Bergman's minimal model. Other assessments included fasting hormone concentrations and lipid profiles, body composition from whole-body dual-energy X-ray absorptiometry, 24-hour ambulatory blood pressure monitoring, and inflammatory markers.

RESULTS

Insulin sensitivity was 34% lower in post-term than in term children (7.7 vs. 11.6 x10⁻⁴·min⁻¹·(mU/l); p<0.0001). There was a compensatory increase in acute insulin response among post-term children (418 vs 304 mU/l; p=0.037), who also displayed lower glucose effectiveness than those born at term (2.25 vs 3.11 x10⁻²·min⁻¹; p=0.047). Post-term children not only had more body fat (p=0.014) and less fat-free mass (p=0.014), but also had increased central adiposity with more truncal fat (p=0.017) and greater android to gynoid fat ratio (p=0.007) compared to term controls. Further, post-term children displayed other markers of the metabolic syndrome: lower normal nocturnal systolic blood pressure dipping (p=0.027), lower adiponectin concentrations (p=0.005), as well as higher leptin (p=0.008) and uric acid (p=0.033) concentrations. Post-term boys (but not girls) also displayed a less favourable lipid profile, with higher total cholesterol (p=0.018) and LDL-C (p=0.006) concentrations, and total cholesterol to HDL-C ratio (p=0.048).

CONCLUSIONS

Post-term children have reduced insulin sensitivity and display a number of early markers of the metabolic syndrome. These findings could have important implications for the management of prolonged pregnancies. Future studies need to examine potential impacts later in life, as well as possible underlying mechanisms.

Increasing maternal age is associated with taller stature and reduced abdominal fat in their children

BACKGROUND

Maternal age at childbirth continues to increase worldwide. We aimed to assess whether increasing maternal age is associated with changes in childhood height, body composition, and metabolism.

METHODS

277 healthy pre-pubertal children, born 37-41 weeks gestation were studied. Assessments included: height and weight corrected for parental measurements, DEXA-derived body composition, fasting lipids, glucose, insulin, and hormonal profiles. Subjects were separated according to maternal age at childbirth: <30, 30-35, and >35 years.

RESULTS

Our cohort consisted of 126 girls and 151 boys, aged 7.4 ± 2.2 years (range 3-10); maternal age at childbirth was 33.3 ± 4.7 years (range 19-44). Children of mothers aged >35 and 30-35 years at childbirth were taller than children of mothers aged <30 years by 0.26 (p = 0.002) and 0.23 (p = 0.042) SDS, respectively. There was a reduction in childhood BMISDS with increasing maternal age at childbirth, and children of mothers aged >35 years at childbirth were 0.61 SDS slimmer than those of mothers <30 years (p = 0.049). Children of mothers aged 30-35 (p = 0.022) and >35 (p = 0.036) years at childbirth had abdominal adiposity reduced by 10% and 13%, respectively, compared to those in the <30 group. Children of mothers aged 30-35 years at childbirth displayed a 19% increase in IGF-I concentrations compared to offspring in <30 group (p = 0.042). Conversely, IGF-II concentrations were lower among the children born to mothers aged 30-35 (6.5%; p = 0.004) and >35 (8.1%; p = 0.005) compared to those of mothers aged <30 years. Girls of mothers aged 30-35 years at childbirth also displayed improved HOMA-IR insulin sensitivity (p = 0.010) compared to girls born to mothers aged <30 years.

CONCLUSIONS

Increasing maternal age at childbirth is associated with a more favourable phenotype (taller stature and reduced abdominal fat) in their children, as well as improved insulin sensitivity in girls.

Olive (Olea europaea L.) leaf polyphenols improve insulin sensitivity in middle-aged overweight men: a randomized, placebo-controlled, crossover trial

BACKGROUND

Olive plant leaves (Olea europaea L.) have been used for centuries in folk medicine to treat diabetes, but there are very limited data examining the effects of olive polyphenols on glucose homeostasis in humans.

OBJECTIVE

To assess the effects of supplementation with olive leaf polyphenols (51.1 mg oleuropein, 9.7 mg hydroxytyrosol per day) on insulin action and cardiovascular risk factors in middle-aged overweight men.

DESIGN

Randomized, double-blinded, placebo-controlled, crossover trial in New Zealand. 46 participants (aged 46.4 ± 5.5 years and BMI 28.0 ± 2.0 kg/m(2)) were randomized to receive capsules with olive leaf extract (OLE) or placebo for 12 weeks, crossing over to other treatment after a 6-week washout. Primary outcome was insulin sensitivity (Matsuda method). Secondary outcomes included glucose and insulin profiles, cytokines, lipid profile, body composition, 24-hour ambulatory blood pressure, and carotid intima-media thickness.

RESULTS

Treatment evaluations were based on the intention-to-treat principle. All participants took >96% of prescribed capsules. OLE supplementation was associated with a 15% improvement in insulin sensitivity (p = 0.024) compared to placebo. There was also a 28% improvement in pancreatic β-cell responsiveness (p = 0.013). OLE supplementation also led to increased fasting interleukin-6 (p = 0.014), IGFBP-1 (p = 0.024), and IGFBP-2 (p = 0.015) concentrations. There were however, no effects on interleukin-8, TNF-α, ultra-sensitive CRP, lipid profile, ambulatory blood pressure, body composition, carotid intima-media thickness, or liver function.

CONCLUSIONS

Supplementation with olive leaf polyphenols for 12 weeks significantly improved insulin sensitivity and pancreatic β-cell secretory capacity in overweight middle-aged men at risk of developing the metabolic syndrome.

Body size and pubertal development explain ethnic differences in structural geometry at the femur in Asian, Hispanic, and white early adolescent girls living in the U.S

Variation in structural geometry is present in adulthood, but when this variation arises and what influences this variation prior to adulthood remains poorly understood. Ethnicity is commonly the focus of research of skeletal integrity and appears to explain some of the variation in quantification of bone tissue. However, why ethnicity explains variation in skeletal integrity is unclear.

METHODS

Here we examine predictors of bone cross sectional area (CSA) and section modulus (Z), measured using dual-energy X-ray absorptiometry (DXA) and the Advanced Hip Analysis (AHA) program at the narrow neck of the femur in adolescent (9-14 years) girls (n=479) living in the United States who were classified as Asian, Hispanic, or white if the subject was 75% of a given group based on parental reported ethnicity. Protocols for measuring height and weight follow standardized procedures. Total body lean mass (LM) and total body fat mass (FM) were quantified in kilograms using DXA. Total dietary and total dairy calcium intakes from the previous month were estimated by the use of an electronic semi-quantitative food frequency questionnaire (eFFQ). Physical activity was estimated for the previous year by a validated self-administered modifiable activity questionnaire for adolescents with energy expenditure calculated from the metabolic equivalent (MET) values from the Compendium of Physical Activities. Multiple regression models were developed to predict CSA and Z.

RESULTS

Age, time from menarche, total body lean mass (LM), total body fat mass (FM), height, total calcium, and total dairy calcium all shared a significant (p<0.05), positive relationship with CSA. Age, time from menarche, LM, FM, and height shared significant (p<0.05), positive relationships with Z. For both CSA and Z, LM was the most important covariate. Physical activity was not a significant predictor of geometry at the femoral neck (p≥0.339), even after removing LM as a covariate. After adjusting for covariates, ethnicity was not a significant predictor in regression models for CSA and Z.

CONCLUSION

Variability in bone geometry at the narrow neck of the femur is best explained by body size and pubertal maturation. After controlling for these covariates there were no differences in bone geometry between ethnic groups.

Psyllium supplementation in adolescents improves fat distribution & lipid profile: a randomized, participant-blinded, placebo-controlled, crossover trial

Aims

We aimed to assess the effects of psyllium supplementation on insulin sensitivity and other parameters of the metabolic syndrome in an at risk adolescent population.

Methods

This study encompassed a participant-blinded, randomized, placebo-controlled, crossover trial. Subjects were 47 healthy adolescent males aged 15–16 years, recruited from secondary schools in lower socio-economic areas with high rates of obesity. Participants received 6 g/day of psyllium or placebo for 6 weeks, with a two-week washout before crossing over. Fasting lipid profiles, ambulatory blood pressure, auxological data, body composition, activity levels, and three-day food records were collected at baseline and after each 6-week intervention. Insulin sensitivity was measured by the Matsuda method using glucose and insulin values from an oral glucose tolerance test.

Results

45 subjects completed the study, and compliance was very high: 87% of participants took >80% of prescribed capsules. At baseline, 44% of subjects were overweight or obese. 28% had decreased insulin sensitivity, but none had impaired glucose tolerance. Fibre supplementation led to a 4% reduction in android fat to gynoid fat ratio (p = 0.019), as well as a 0.12 mmol/l (6%) reduction in LDL cholesterol (p = 0.042). No associated adverse events were recorded.

Conclusions

Dietary supplementation with 6 g/day of psyllium over 6 weeks improves fat distribution and lipid profile (parameters of the metabolic syndrome) in an at risk population of adolescent males.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12609000888268

Epidemiologic behavior of obesity in the Maracaibo City metabolic syndrome prevalence study

Introduction

Obesity is a worldwide public health issue. Since the epidemiological behaviour of this disease is not well established in our country, the purpose of this study was to determinate its prevalence in the Maracaibo City, Zulia State- Venezuela.

Materials and Methods

A cross-sectional study was undertaken using the data set from the Maracaibo City Metabolic Syndrome Prevalence Study. The sample consists of 2108 individuals from both genders and randomly selected: 1119 (53.09%) women and 989 (46.91%) men. The participants were interrogated for a complete clinical history and anthropometric measurements. To classify obesity, the WHO criteria for Body Mass Index (BMI), and Waist Circumference (WC) from the IDF/NHLBI/AHA/WHF/IAS/IASO-2009 (IDF-2009) and ATPIII statements were applied.

Results

For BMI, obesity had an overall prevalence of 33.3% (n = 701), and according to gender women had 32.4% (n = 363) and men had 34.2% (n = 338). Overweight had a prevalence of 34.8% (n = 733), Normal weight had 29.8% (n = 629), and Underweight had 2.1% (n = 45). Adding Obesity and Overweight results, the prevalence of elevated BMI (>25 Kg/m²) was 68.1%. Using the IDF-2009 WC's cut-off, Obesity had 74.2% prevalence, compared to 51.7% using the ATPIII parameters.

Conclusions

These results show a high prevalence of abdominal obesity in our locality defined by the WHO, IDF-2009 and ATPIII criteria, which were not designed for Latin-American populations. We suggest further investigation to estimate the proper values according to ethnicity, genetic background and sociocultural aspects.

Asian ethnicity is associated with a higher trunk/peripheral fat ratio in women and adolescent girls

Background

Ethnic differences in body fat mass and distribution may develop in childhood and contribute to increased obesity-related disease risk among Asians. We used dual-energy X-ray absorptiometry (DXA) to evaluate adiposity measures among adult women and their adolescent daughters, who were of predominantly Japanese and white ethnicity.

Methods

We obtained DXA whole body scans for 101 mothers aged 30 years or older and 112 daughters aged 10 to 16 years. The participants were classified as Asian, part-Asian, mixed/other, or white. As a measure of central adiposity, we calculated the trunk/peripheral fat ratio (TPFR). General linear models were used to evaluate differences in adiposity measures by ethnic category.

Results

In mothers, TPFR was significantly higher (P_trend < 0.01) in Asians and part-Asians (1.38 ± 0.42 and 1.32 ± 0.51) than in mixed/others and whites (1.18 ± 0.27 and 1.09 ± 0.21). The trend was similar among daughters (P_trend < 0.001), with respective values of 1.09 ± 0.18, 0.97 ± 0.17, 0.99 ± 0.16, and 0.87 ± 0.11. Among mothers, gynoid fat mass and peripheral fat mass were significantly lower in Asians than in whites, whereas none of the regional DXA adiposity measures differed by ethnicity in daughters.

Conclusions

These results confirm previous reports of greater central adiposity in women of Asian ancestry and indicate that ethnic differences in adiposity are already present in adolescence.

Sleep deprivation predisposes gujarati Indian adolescents to obesity

Background and Aim:

Recent studies on various populations indicate that lack of sleep is one of the potential risk factors predisposing the youth to obesity. Since there is a significant rise in obesity among Indian youth and because research indicating the role of sleep in development of obesity among Indian population is scant, the current study was undertaken to assess the effect of sleep duration on adiposity among Gujarati Indian adolescents.

Materials and Methods:

A randomized cross-sectional study was done on 489 voluntarily participating Indian adolescents in the age group of 16-19 years. Participants were grouped into two categories 1). Adequate Sleep Duration at Night (more than seven hours, ASDN) and 2) Inadequate Sleep Duration at Night (less than seven hours, IASDN) as reported by the participants. The participants were later assessed for adiposity in terms of BMI, BF %, FM, FMI and waist circumference, meal frequency per day and physical activity status.

Results:

In both boys as well as girls, the BMI, BF%, FM and FMI were significantly lower in the ASDN group than the IASDN group. However, there was an insignificant difference in the meal frequency and physical activity status between the ASDN and IASDN group.

Conclusion:

Inadequate sleep duration increases adiposity among Gujarati Indian adolescents but further studies are required to find out the mechanisms through which sleep affects adiposity in this population.

Association of sleep duration with arterial blood pressure profile of gujarati Indian adolescents

Background and Aim:

Recently, National Health and Nutritional Examination Survey-1 data analysis found short sleep duration as a risk factor for hypertension in the U.S. population. However, since ethnic differences exist in the aetiopathogenesis of diseases, the current study was undertaken to study the effect of sleep duration on the blood pressure profile of Gujarati Indian adolescents.

Materials and Methods:

A cross-sectional study was conducted on 489 Gujarati Indian adolescents of age group 16-19 years studying in school and colleges in the local population. The participants were assessed for their sleep duration, physical activity status, body composition, blood pressure profile and cardiovascular reactivity. The sleep duration was reported by the subjects as the number of hours they slept on most of the nights in a week over the last one year. The observations of the study were then analyzed after grouping them into: 1) Adequate Sleep Duration at Night, ASDN (≥7 hrs) and 2) Inadequate Sleep Duration at Night, ISDN (<7 hrs) groups. Student's unpaired t-test was used to study if any significant difference (P< 0.05) existed between the groups.

Results:

No significant difference was found in Systolic blood pressure, Diastolic blood pressure, Pulse pressure and Mean arterial pressure between the ASDN group and the ISDN group. Physical activity status also did not differ between the two groups. However, adolescents of ISDN group showed a significantly higher level of adiposity and cardiovascular reactivity as compared to adolescents of ASDN group.

Conclusion:

Although short sleep duration is associated with a higher level of adiposity and cardiovascular reactivity in Gujarati Indian adolescents, it does not affect the resting blood pressure profile of these adolescents. However, longitudinal studies would be required to observe if the changes in adiposity and cardiovascular reactivity affect these adolescents in later life.

Ethnic differences in body fat distribution among Asian pre-pubertal children: a cross-sectional multicenter study

Background

Ethnic differences in body fat distribution contribute to ethnic differences in cardiovascular morbidities and diabetes. However few data are available on differences in fat distribution in Asian children from various backgrounds. Therefore, the current study aimed to explore ethnic differences in body fat distribution among Asian children from four countries.

Methods

A total of 758 children aged 8-10 y from China, Lebanon, Malaysia and Thailand were recruited using a non-random purposive sampling approach to enrol children encompassing a wide BMI range. Height, weight, waist circumference (WC), fat mass (FM, derived from total body water [TBW] estimation using the deuterium dilution technique) and skinfold thickness (SFT) at biceps, triceps, subscapular, supraspinale and medial calf were collected.

Results

After controlling for height and weight, Chinese and Thai children had a significantly higher WC than their Lebanese and Malay counterparts. Chinese and Thais tended to have higher trunk fat deposits than Lebanese and Malays reflected in trunk SFT, trunk/upper extremity ratio or supraspinale/upper extremity ratio after adjustment for age and total body fat. The subscapular/supraspinale skinfold ratio was lower in Chinese and Thais compared with Lebanese and Malays after correcting for trunk SFT.

Conclusions

Asian pre-pubertal children from different origins vary in body fat distribution. These results indicate the importance of population-specific WC cut-off points or other fat distribution indices to identify the population at risk of obesity-related health problems.

Effects of increasing dietary protein and fibre intake with lupin on body weight and composition and blood lipids in overweight men and women

BACKGROUND

Lupin kernel flour (LKF) is a novel food ingredient that is high in protein and fibre. We have previously shown that partial substitution of refined wheat-derived carbohydrate in bread with protein and fibre from LKF can reduce appetite and energy intake acutely. In addition, several studies have suggested that lupin may reduce cholesterol concentrations and benefit glucose and insulin metabolism.

AIM

The aim of this study was to investigate the effects on body weight and composition and blood lipids, glucose and insulin of an ad libitum LKF-enriched diet higher in dietary protein and fibre.

SUBJECTS AND METHODS

A total of 88 overweight and obese men and women were recruited for a 16-week parallel-design randomized controlled trial. Participants replaced 15-20% of their usual daily energy intake with white bread (control) or LKF-enriched bread (lupin) in an ad libitum diet. Measurements of body weight and composition, and fasting blood biochemical measurements were performed at baseline and 16 weeks. The primary analysis included 74 participants (37 per group) who completed the intervention.

RESULTS

At baseline, mean (+/-s.d.) body mass index and total cholesterol were 30.6+/-3.5 kg m(-2) and 5.37+/-0.94 mmol l(-1), respectively. Estimated (mean between-group difference (95% confidence interval)) protein (13.7 (2.28, 25.0) g per day) and fibre (12.5 (8.79, 16.2) g per day) intakes were higher during the intervention with lupin than with control. For lupin relative to control, the net effects on body weight (-0.4 (-1.3, 0.6) kg), fat mass (-0.5 (-1.1, 0.2) kg) and percentage (-0.5 (-1.1, 0.1)%), plasma leptin (-1.66 (-4.91, 1.59) ng ml(-1)) and adiponectin (0.20 (-0.73, 1.13) mg l(-1), as well as serum total cholesterol (-0.08 (-0.38, 0.22) mmol l(-1)), triglycerides (0.09 (-0.10, 0.21) mmol l(-1)), glucose (0.10 (-0.11, 0.30) mmol l(-1)) and insulin (0.40 (-1.20, 2.00) mU l(-1)) were not significant.

CONCLUSIONS

This study does not support the proposal that an ad libitum diet enriched in LKF resulting in moderate changes in both protein and fibre intakes can benefit body weight and composition or fasting blood lipids, glucose and insulin concentrations in overweight men and women with mildly elevated total cholesterol concentrations.

Racial and ethnic differences in reproductive potential across the life cycle

OBJECTIVE

To review variations in specific reproductive health outcomes by race and ethnicity. A growing number of reports have explored potential gaps in the quality of reproductive health and healthcare across racial and ethnic groups. Diverse results from numerous investigations have made it challenging for practitioners to confirm the significance of these disparities.

METHOD(S)

Three specific areas of the reproductive life cycle were examined: pubertal onset, outcomes from treatment with assisted reproductive technologies (ART), and the menopausal transition. These areas were selected as they encompass a continuum of events across the reproductive life span of women. Outcomes were compared in black, white, Asian, and Hispanic women. Medline searches querying on keywords puberty, IVF, ART, menopause, menopausal symptoms, racial disparity, race, Asian, Japanese, Chinese, African American, black, Hispanic, and Latino were performed to isolate relevant publications for review.

RESULT(S)

Differences across race and ethnicity were noted in each clinical endpoint. The most notable findings included earlier puberty in blacks and Hispanics compared with whites, significantly lower live birth rates after ART in all racial and ethnic groups compared with whites, and differences in perimenopausal symptomatology and possibly timing in various racial/ethnic groups compared with whites. Additional research is needed to completely unravel the full significance and basic underpinnings of these disparities. Some of the limitations of the current state of the literature in drawing conclusions about the independent effect of race/ethnicity on reproductive disparities include small samples sizes in some studies, inconsistencies in the characterization of racial/ethnic groups, and incomplete control of potential confounding.

CONCLUSION(S)

Race and ethnicity appear to be important correlates of outcomes from the initiation of reproduction functioning through to its conclusion. The ultimate goal of identifying racial disparities in reproduction is to isolate the basic determinants of disparities and formulate strategies to improve outcomes for women at risk. The differences demonstrated in this review of the literature could represent environmental, sociocultural, and/or genetic correlates of race that influence these important milestones.

Gender differences in total and regional body composition changes as measured by dual-energy x-ray absorptiometry in Korean children and adolescents

The objective of this study was to gain normal reference values and to evaluate gender differences in total and regional body composition changes according to age and Tanner stage by dual-energy X-ray absorptiometry in Korean. Four hundred and forty-nine healthy subjects, aged 5-20 yr were enrolled. Until 9 yr of age, males had a higher lean tissue mass and a lower percent body fat (%BF) than the females (12.6% vs 10.0%, p<0.01). These differences were not evident from 10 to 12.9 yr because of early pubertal progression in girls. After 13 yr, a significant sex difference in the body compositions were observed again. In late teens, females have higher %BF than males (25.6% vs 12.3%, p<0.01). However, females have lower android-gynoid percent fat ratio than males at Tanner stages (TSs) 4 and 5 (p<0.01). These differences are because of significant increase of gynoid lean tissue mass after 13 yr in males. The reference data would be useful for future research related to growth and obesity in Korean children and adolescents.

Breast density assessment in adolescent girls using dual-energy X-ray absorptiometry: a feasibility study

Breast density, the radiographically opaque fraction of the breast in a mammogram, is one of the strongest biomarkers of breast cancer risk. However, younger populations do not typically have mammograms due to radiation concerns. This study explored a commercially available dual-energy X-ray absorptiometer (DXA) system as a low-dose method to measure breast fibroglandular density in adolescent girls. Eighteen girls (13-14 years old) indicated their breast development according to Tanner and underwent three dedicated DXA scans, two of their left and one of their right breasts. Total projected breast area was manually delineated on each image and percent fibroglandular volume density (%FGV), absolute fibroglandular volume (FGV), total breast area, and volume were computed. It was possible to image breasts representing all five Tanner stages; %FGV ranged from 31.9% to 92.2% with a mean of 71.1 +/- 14.8%, whereas FGV ranged from 80 to 270 cm(3) with a mean of 168 +/- 54 cm(3). Left and right breast %FGV were highly correlated (r(p) = 0.97, P < 0.0001) and of the same magnitude (P = 0.18). However, left total volume and FGV were larger than the right by 38 cm(3) (P = 0.04) and 19 cm(3) (P = 0.02), respectively. Total volume and FGV increased by Tanner stage, whereas %FGV did not. Our method had excellent precision for %FGV and moderate precision for FGV (root mean square SDs of 2.4% and 16.6 cm(3)). These pilot data indicate that dedicated DXA breast scans may be useful in studies exploring breast density in girls.