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Background: Accurate assessment of body composition during infancy is an important marker of early growth. This study aimed to develop anthropometric models to predict body composition in 3-24-month-old infants from diverse socioeconomic settings and ethnic groups., Methods: An observational, longitudinal, prospective, multi-country study of infants from 3 to 24 months with body composition assessed at three monthly intervals using deuterium dilution (DD) and anthropometry. Linear mixed modelling was utilized to generate sex-specific fat mass (FM) and fat-free mass (FFM) prediction equations, using length(m), weight-for-length (kg/m), triceps and subscapular skinfolds and South Asian ethnicity as variables. The study sample consisted of 1896 (942 measurements from 310 girls) training data sets, 941 (441 measurements from 154 girls) validation data sets of 3-24 months from Brazil, Pakistan, South Africa and Sri Lanka. The external validation group (test) comprised 349 measurements from 250 (185 from 124 girls) infants 3-6 months of age from South Africa, Australia and India., Results: Sex-specific equations for three age categories (3-9 months; 10-18 months; 19-24 months) were developed, validated on same population and externally validated. Root mean squared error (RMSE) was similar between training, validation and test data for assessment of FM and FFM in boys and in girls. RMSPE and mean absolute percentage error (MAPE) were higher in validation compared to test data for predicting FM, however, in the assessment of FFM, both measures were lower in validation data. RMSE for test data from South Africa (M/F-0.46/0.45 kg) showed good agreement with validation data for assessment of FFM compared to Australia (M/F-0.51/0.33 kg) and India(M/F-0.77/0.80 kg)., Conclusions: Anthropometry-based FFM prediction equations provide acceptable results. Assessments based on equations developed on similar populations are more applicable than those developed from a different population., (© 2024. The Author(s).)

Background: Given the importance of infancy for establishing growth trajectories, with later-life health consequences, we investigated longitudinal body composition among infants from six economically and ethnically diverse countries., Methods: We recruited mother-infant dyads using the WHO Multicenter Growth Reference Study criteria. We measured fat-free mass (FFM) in 1393 (49% female) infants from birth to 6 months of age (Australia, India, and South Africa; n = 468), 3-24 months of age (Brazil, Pakistan, South Africa, and Sri Lanka; n = 925), and derived fat mass (FM), fat mass index (FMI), and fat-free mass index (FFMI). Height-for-age (HAZ), weight-for-age (WAZ), and weight-for-length (WHZ) Z-scores were computed. Sex differences were assessed using a t-test, and country differences using a one-way analysis of covariance. We further compared subsamples of children with average (-0.25 > HAZ < +0.25), below-average (≤-0.25) and above-average (≥+0.25) HAZ., Results: HAZ performed well between 0 and 6 months, but less so between 3 and 24 months. The stunting prevalence peaked at 10.3% for boys and 7.8% for girls, at 24 months. By 24 months, girls had greater FMI (10%) than boys. There were significant differences in FFM (both sexes in all countries) and FM (Brazilian boys, Pakistani and South African girls) by 24 months of age between infants with average, above-average, and below-average HAZ., Conclusion: In a multi-country sample representing more ideal maternal conditions, body composition was heterogeneous even among infants who exhibited ideal length. Having a mean HAZ close to the median of the WHO standard for length reduced FFM between-country heterogeneity but not FM, suggesting that other factors may influence adiposity., (© 2024. The Author(s).)

Background/objectives: Two compartment (2 C) models of body composition, including Air Displacement Plethysmography (ADP) and Deuterium Dilution (DD), assume constant composition of fat-free mass (FFM), while 3-compartment (3 C) model overcomes some of these assumptions; studies are limited in infants. The objective of the present study is to compare 3 C estimates of body composition in 6-mo. old infants from Australia, India, and South Africa, including FFM density and hydration, compare with published literature and to evaluate agreement of body composition estimates from ADP and DD., Methods: Body volume and water were measured in 176 healthy infants using ADP and DD. 3C-model estimates of fat mass (FM), FFM and its composition were calculated, compared between countries (age and sex adjusted) and with published literature. Agreement between estimates from ADP and DD were compared by Bland-Altman and correlation analyses., Results: South African infants had significantly higher % FM (11.5%) and density of FFM compared to Australian infants. Australian infants had significantly higher % FFM (74.7 ± 4.4%) compared to South African infants (71.4 ± 5.0) and higher FFMI (12.7 ± 0.8 kg/m 2 ) compared to South African (12.3 ± 1.2 kg/m 2 ) and Indian infants (11.9 ± 1.0 kg/m 2 ). FFM composition of present study differed significantly from literature. Pooled three country estimates of FM and FFM were comparable between ADP and DD; mean difference of -0.05 (95% CI: -0.64, +0.55) kg and +0.05 (95% CI: -0.55, +0.64) kg., Conclusions: 3C-model estimates of body composition in infants differed between countries; future studies are needed to confirm these findings and investigate causes for the differences., (© 2023. The Author(s).)

Objectives: There's paucity of longitudinal studies assessing the role of adolescent growth on adult body composition in developing countries. The aims of this study were to assess the association between adolescent change in height, weight and BMI and early adult height, weight, body fat and lean mass., Methods: Magnitude, timing and intensity of height, weight and BMI growth were modelled for participants from the Birth to Thirty (Bt30) cohort (7-23 years). Early adult height, weight, BMI and DXA-derived body composition were obtained 1881 black participants (21-24 years). Linear regression analyses were used to assess associations., Results: Adolescents with an earlier onset of puberty were heavier in childhood and had an earlier timing and faster weight gain velocity in late adolescence. The intensity of adolescent weight gain was positively associated with adult BMI and fat mass index (FMI) in females. Early timing of adolescent BMI gain was associated with increased weight and BMI in adult females and FMI in adult males. Achieving peak weight velocity around age at peak height velocity was associated with lower BMI and fat mass in both sexes., Conclusion: This study confirms the adverse consequences of excessive weight gain prior to puberty, which is associated with an earlier and faster resurgence in weight gain velocity in early adulthood. Factors that contribute to an asynchronous timing of ages of peak weight and peak height velocities may accentuate the risk of adult obesity., (© 2023. The Author(s).)

Background/objective: Available evidence on infant body composition is limited. This study aimed to investigate factors associated with body composition at 6 and 24 months., Subjects/methods: Multicenter study with data from a 0 to 6-mo cohort (Australia, India and South Africa) and a 3 to 24-mo cohort (Brazil, Pakistan, South Africa, and Sri Lanka). For the 0-6-mo cohort, body composition was assessed by air-displacement plethysmography (ADP) and for the 3-24-month cohort by the deuterium dilution (DD) technique. Fat mass (FM), fat-free mass (FFM), FM index (FMI), and FFM index (FFMI) were calculated. Independent variables comprised the Gini index of the country, maternal and infant characteristics, and breastfeeding pattern at 3 months. For the 3-24-mo cohort, breastfeeding, and minimum dietary diversity (MDD) at 12 months were also included. Crude and adjusted analyses stratified by sex were conducted by multilevel modelling using mixed models., Results: At 6 months, every 1 kg increase in birth weight was associated with an increase of 0.716 kg in FFM and 0.582 kg/m 2 in FFMI in girls, whereas in boys, the increase was of 0.277 kg in FFM. At 24 months, compared to those weaned before 12 months, girls still breastfed at 12 months presented a decrease of 0.225 kg in FM, 0.645 kg in FFM and 0.459 kg/m 2 in FFMI, and in boys the decreases were of 0.467 kg in FM, 0.603 kg in FFM and 0.628 kg/m 2 in FFMI., Conclusion: Birth weight and breastfeeding are independent predictors of body composition in early life, irrespective of sex., (© 2023. The Author(s).)

Providing all infants with the best start to life is a universal but challenging goal for the global community. Historically, the size and shape of infants, quantified by anthropometry and commencing with birthweight, has been the common yardstick for physical growth and development. Anthropometry has long been considered a proxy for nutritional status during infancy when, under ideal circumstances, changes in size and shape are most rapid. Developed from data collected in the Multicentre Growth Reference Study (MGRS), WHO Child Growth Standards for healthy infants and children have been widely accepted and progressively adopted. In contrast, and somewhat surprisingly, much less is understood about the 'quality' of growth as reflected by body composition during infancy. Recent advances in body composition assessment, including the more widespread use of air displacement plethysmography (ADP) across the first months of life, have contributed to a progressive increase in our knowledge and understanding of growth and development. Along with stable isotope approaches, most commonly the deuterium dilution (DD) technique, the criterion measure of total body water (TBW), our ability to quantify lean and fat tissue using a two-compartment model, has been greatly enhanced. However, until now, global reference charts for the body composition of healthy infants have been lacking. This paper details some of the historical challenges associated with the assessment of body composition across the first two years of life, and references the logical next steps in growth assessments, including reference charts., (© 2023. The Author(s).)

Introduction: The impact of infection on infant nutritional status, body size, and growth is well documented. However, research into the impact of infection on infant body composition is limited. Greater understanding is, therefore, needed on the effects of infection in early life., Methods: Associations between a composite morbidity index consisting of the sum of the cumulative tallies for a range of symptoms representing infection and morbidity in the infants and nutritional status (height-for-age (HAZ), and weight-for-height (WHZ)), and body composition (fat-free mass (FFM), fat mass (FM), fat-free mass index (FFMI), and fat mass index (FMI)) at 6 months of age were investigated using hierarchical regression analysis., Results: The sample comprised data between birth and 6 months postnatally, of 156 infants who were a priori born healthy in Soweto, South Africa. Morbidity, over the cumulative period of birth to 6 months, was associated with lower FMI (β = -1.77) and lower FM (β = -0.61), and conversely with higher FFM (β = 0.94), in infants at 6 months. No associations were found between the morbidity index and FFMI, HAZ, and WHZ. Increased birthweight was associated with a higher FFM (β = 0.66), HAZ (β = 1.14), and WHZ (β = 0.87). Finally, safely managed sanitation facilities, representative of reduced environmental exposure to fecal-oral transmission pathways were associated with a higher HAZ (β = 1.21)., Discussion: Reduction in FMI and FM and exposure to inflammatory cytokines associated with mounting an immune response could alter phenotypic trajectories during to this period of plasticity. From a public health perspective, these results imply that it is important to intensify efforts to prevent infection in infants in the first 6 months postnatally, and that these efforts should concentrate on access to safely managed sanitation facilities., (© 2023 The Authors. American Journal of Human Biology published by Wiley Periodicals LLC.)

Background: Growth patterns may be indicative of underlying changes in body composition. However, few studies have assessed the association of growth and body composition in poorly resourced regions experiencing the double-burden of malnutrition exists. Thus, the aims of this study were to investigate the association of intrauterine and postnatal growth patterns with infant body composition at 2 years in a middle-income country., Methods: Participants were from the International Atomic Energy Agency Multicentre Body Composition Reference study. Fat mass (FM), fat free mass (FFM), Fat mass index (FMI), fat free mass index (FFMI), and percentage fat mass (%FM) were measured in 113 infants (56 boys and 57 girls), from Soweto, South Africa, using deuterium dilution from 3 to 24 months. Birthweight categories were classified using the INTERGROWTH-21 standards as small (SGA), appropriate (AGA), and large-for gestational age (LGA). Stunting (> -2 SDS) was defined using the WHO child growth standards. Birthweight z-score, conditional relative weight and conditional length at 12 and 24 mo were regressed on body composition at 24 mo., Results: There were no sex differences in FM, FFM, FMI and FFMI between 3 and 24 mo. SGA and AGA both had significantly higher %FM than LGA at 12 mo. LGA had higher FM at 24 mo. Children with stunting had lower FM (Mean = 1.94, 95% CI; 1.63-2.31) and FFM (Mean = 5.91, 95% CI; 5.58-6.26) at 12 mo than non-stunting, while the reverse was true for FFMI (Mean = 13.3, 95% CI; 12.5-14.2) at 6 mo. Birthweight and conditionals explained over 70% of the variance in FM. CRW at both 12 and 24 mo was positively associated with FM and FMI. CRW at 12 mo was also positively associated with FMI, while CH at 24 mo was negatively associated with both FFMI and FMI in boys., Conclusion: Both LGA and SGA were associated with higher body fat suggesting that both are disadvantaged nutritional states, likely to increase the risk of obesity. Growth patterns through infancy and toddler period (1-2 years) are indicative of body fat, while growth patterns beyond infancy are less indicative of fat-free mass., (© 2023. The Author(s).)

Background: Body composition assessment in the first 2 y of life provides important insights into child nutrition and health. The application and interpretation of body composition data in infants and young children have been challenged by a lack of global reference data., Objectives: We aimed to develop body composition reference charts of infants aged 0-6 mo based on air displacement plethysmography (ADP) and those aged 3-24 mo based on total body water (TBW) by deuterium dilution (DD)., Methods: Body composition was assessed by ADP in infants aged 0-6 mo from Australia, India, and South Africa. TBW using DD was assessed for infants aged 3-24 mo from Brazil, Pakistan, South Africa, and Sri Lanka. Reference charts and centiles were constructed for body composition using the lambda-mu-sigma method., Results: Sex-specific reference charts were produced for FM index (FMI), FFM index (FFMI), and percent FM (%FM) for infants aged 0-6 mo (n = 470 infants; 1899 observations) and 3-24 mo (n = 1026 infants; 3690 observations). When compared with other available references, there were observable differences but similar patterns in the trajectories of FMI, FFMI, and %FM., Conclusions: These reference charts will strengthen the interpretation and understanding of body composition in infants across the first 24 mo of life., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

This study aimed to evaluate the association of longitudinal nutrient patterns with body composition in a cohort of 132 black South African middle-aged women over five years. Nutrient patterns were identified using principal component analysis at baseline and follow-up 5 years later. Associations between nutrient patterns and repeated body composition measures were evaluated using generalized estimating equations, before and after adjusting for baseline education and repeated measures of age, socio-economic status, physical activity and employment. The animal-driven nutrient pattern was associated with increases in repeated measures of visceral adipose tissue (VAT) (β coefficient, 5.79 [95% CI, 0.01-11.57] cm 2 ), fat mass index (FMI) (0.47 [0.01-0.93] kg·m -2 ) and lean mass index (LMI) (0.50 [0.18-1.17] kg·m -2 ) ( p < 0.05) after adjustment. Vitamin C, sugar, and potassium-driven nutrient pattern was associated with higher FMI (0.50 [0.12-0.88] kg·m -2 ) and LMI (0.58 [0.07-1.10] kg·m -2 ) before and after adjustment ( p < 0.05). These findings suggest that dietary interventions to curb obesity in black middle-aged South African women should focus on attenuation of nutrient patterns centred on added sugar, animal fat and animal protein.

Background: Adolescence is marked by a decline in physical activity, rapid physical growth and changes in body composition, which have been linked to body composition. Prospective data on these associations are rare, particularly in Africa., Aim: The aim of this study was to examine the association of longitudinal patterns across adolescent in physical activity, sedentary behavior and sleep, with anthropometry and body composition at age 18 years in urban South Africa., Methods: We analyzed data from the Birth-to-Twenty Plus Cohort (Bt20+), a longitudinal study of children born in 1990 in Soweto-Johannesburg, South Africa. We used general linear models to investigate the association of adolescent (ages 12 to 18 years) longitudinal trends in physical activity, sedentary behavior and schoolnight sleep and overall physical activity patterns, with body mass index (BMI), waist circumference, fat mass index (FMI), lean mass index (LMI) and percent body fat at age 18 years., Results: The final study sample included 1337 participants with anthropometric measurements (52% female) and 958 participants with body composition measurements (53% female). Males who were consistently more active and consistently walked to school over adolescence had lower waist circumference (B = - 2.0, 95% CI: - 3.9 to - 0.2), FMI (B = - 0.8, 95%: CI: - 1.2 to - 0.1) and percent body fat (B = -2.9, 95% CI: - 4.9 to - 0.9) at age 18 years than those who decreased activity and did not walk to school. Consistently-sedentary females had higher waist circumference than those whose sedentary behavior increased over adolescence (B = 5.4, 95% CI: 0.2 to 10.6). Males who reported sleeping 9 h or more per night on schoolnights had significantly lower BMI (B = -1.0, 95% CI: - 1.4 to- 0.5), and percent body fat (B = -1.5, 95%CI - 2.8 to - 0.1) than those who reported sleeping 8 h or less per night., Conclusion: Patterns of adolescent physical activity, sedentary behavior and sleep are related to young-adult body composition in urban South Africa. These modifiable behaviors may be paths for public health interventions to curb overweight and obesity in many low- or middle-income countries.

Background/objectives: Childhood rapid growth and earlier puberty onset have been associated with adult obesity. However, the association between childhood stunting, pubertal timing and adult obesity is unclear. We examined whether the relationship between stunting at age 2 years (y) and body composition at 23 years is mediated by adolescent body mass index, and pubertal development, using the Birth-to-Twenty Plus cohort (South Africa)., Subjects/methods: For 1036 participants, data on anthropometrics between birth and 23 years, maternal factors, and pubertal development (Tanner scale at 9-16 years) were collected. Stunting at 2 years (height-for-age z-score < -2), 5-18 years BMI-for-age trajectories, pubertal development trajectories, and DXA-derived fat mass (FM) and fat free mass (FFM) at 23 years were determined. Data were analysed using hierarchical regressions and structural equation models., Results: Stunting was directly associated with slower pubertal development and with shorter adult stature, but was not associated with adolescent BMI trajectories, adult FM or FFM. However, stunting was indirectly associated with adult FM and FFM through the direct associations between slower pubertal development and lower FM and between shorter height and lower FFM. BMI trajectories were independently associated with FM and FFM., Conclusions: Being stunted in this population predicted adult body composition through slower pubertal development and shorter adult stature.

Obesity is more prevalent in black South African women than men. However, little is known about the nutrient patterns associated with body composition indices in black African women. Principle Component Analysis (PCA) was applied to 25 nutrients derived from quantified food frequency questionnaires (QFFQs) in 498 middle aged black South African women. Three nutrient patterns, the plant driven, animal driven and Vitamin C, sugar and potassium driven nutrient patterns, accounted for 59% of the variance of nutrient intake. Linear models of the body composition parameters as outcome variables indicated that a standard deviation increase in the animal driven nutrient pattern was significantly associated with increases in body mass index (BMI) (1.29 kg·m -2 (95% CI, 0.54-2.04; p = 0.001), subcutaneous adipose tissue (SAT) (26.30 cm 2 (7.97-44.63); p = 0.005), visceral adipose tissue (VAT) (9.88 cm 2 (5.13-14.63); p < 0.001), VAT/SAT ratio (0.01 (0.00-0.02); p = 0.018), whole body fat mass index (0.74 kg·m -2 (0.25-1.22); p = 0.003), and whole body lean mass index (0.53 kg·m -2 (0.23-0.83); p = 0.001). An increase in plant driven nutrient pattern was significantly associated with an increase in SAT of 20.45 cm 2 (0.47-40.43); p = 0.045. This study demonstrates that animal driven nutrient pattern, characterised by the consumption of more animal protein and fat nutrients, similar to the western diet is associated with increased body fat and lean mass.

Objectives: Varying hypertension prevalence across different socioeconomic strata within a population has been well reported. However, the causal factors and pathways across different settings are less clear, especially in sub-Saharan Africa. Therefore, this study aimed to compare blood pressure (BP) levels and investigate the extent to which socioeconomic status (SES) is associated with BP, in rural and urban South Africa women., Setting: Rural and urban South Africa., Design: Cross-sectional., Participants: Cross-sectional data on SES, total moderate and vigorous physical activity (MVPA), anthropometric and BP were collected on rural (n=509) and urban (n=510) young black women (18-23 years age). Pregnant and mentally or physically disabled women were excluded from the study., Results: The prevalence of combined overweight and obesity (46.5% vs 38.8%) and elevated BP (27.0% vs 9.3%) was higher in urban than rural women, respectively. Results from the structural equation modelling showed significant direct positive effects of body mass index (BMI) on systolic BP (SBP) in rural, urban and pooled datasets. Negative direct effects of SES on SBP and positive total effects of SES on SBP were observed in the rural and pooled datasets, respectively. In rural young women, SES had direct positive effects on BMI and was negatively associated with MVPA in urban and pooled analyses. BMI mediated the positive total effects association between SES and SBP in pooled analyses (ß 0.46; 95% CI 0.15 to 0.76)., Conclusions: Though South Africa is undergoing nutritional and epidemiological transitions, the prevalence of elevated BP still varies between rural and urban young women. The association between SES and SBP varies considerably in economically diverse populations with BMI being the most significant mediator. There is a need to tailor prevention strategies to take into account optimising BMI when designing strategies to reduce future risk of hypertension in young women., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY. Published by BMJ.)

Objective: The latest genome-wide association studies of obesity-related traits have identified several genetic loci contributing to body composition (BC). These findings have not been robustly replicated in African populations, therefore, this study aimed to assess whether European BC-associated gene loci played a similar role in a South African black population., Methods: A replication and fine-mapping study was performed in participants from the Birth to Twenty cohort (N = 1,926) using the Metabochip. Measurements included body mass index (BMI), waist and hip circumference, waist-to-hip ratio (WHR), total fat mass, total lean mass and percentage fat mass (PFM)., Results: SNPs in several gene loci, including SEC16B (P adj  <  9.48 × 10 -7 ), NEGR1 (P adj  < 1.64 × 10 -6 ), FTO (P adj  < 2.91 × 10 -5 ), TMEM18 (P adj  < 2.27 × 10 -5 ), and WARS2 (P adj  < 3.25 × 10 -5 ) were similarly associated (albeit not at array-wide signficance (P ≤ 6.7 × 10 -7 ) with various phenotypes including fat mass, PFM, WHR linked to BC in this African cohort, however the associations were driven by different sentinel SNPs. More importantly, DXA-derived BC measures revealed stronger genetic associations than simple anthropometric measures. Association signals generated in this study were shared by European and African populations, as well as unique to this African cohort. Moreover, sophisticated estimates like DXA measures enabled an enhanced characterisation of genetic associations for BC traits., Conclusion: Results from this study suggest that in-depth genomic studies in larger African cohorts may reveal novel SNPs for body composition and adiposity, which will provide greater insight into the aetiology of obesity.

Background: The growing prevalence of overweight and obesity in low- or middle-income countries precipitates the need to examine early life predictors of adiposity., Objectives: To examine growth trajectories from birth, and associations with adult body composition in the Birth to Twenty Plus Cohort, Soweto, South Africa., Methods: Complete data at year 22 was available for 1088 participants (536 males and 537 females). Conditional weight and height indices were generated indicative of relative rate of growth between years 0-2, 2-5, 5-8, 8-18, and 18-22. Whole body composition was measured at year 22 (range 21-25 years) using dual energy x-ray absorptiometry (DXA). Total fat free soft tissue mass (FFSTM), fat mass, and abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were recorded., Results: Birth weight was positively associated with FFSTM and fat mass at year 22 (β = 0.11, p<0.01 and β = 0.10, p<0.01 respectively). Relative weight gain from birth to year 22 was positively associated with FFSTM, fat mass, VAT, and SAT at year 22. Relative linear growth from birth to year 22 was positively associated with FFSTM at year 22. Relative linear growth from birth to year 2 was positively associated with VAT at year 22. Being born small for gestational age and being stunted at age 2 years were inversely associated with FFSTM at year 22., Conclusions: The importance of optimal birth weight and growth tempos during early life for later life body composition, and the detrimental effects of pre- and postnatal growth restriction are clear; yet contemporary weight-gain most strongly predicted adult body composition. Thus interventions should target body composition trajectories during childhood and prevent excessive weight gain in early adulthood.

Purpose . The purpose of this research was to collect data to inform intervention strategies to optimise body composition in South African preschool children. Methods . Data were collected in urban and rural settings. Weight status, physical activity, and gross motor skill assessments were conducted with 341 3-6-year-old children, and 55 teachers and parents/caregivers participated in focus groups. Results . Overweight and obesity were a concern in low-income urban settings (14%), but levels of physical activity and gross motor skills were adequate across all settings. Focus group findings from urban and rural settings indicated that teachers would welcome input on leading activities to promote physical activity and gross motor skill development. Teachers and parents/caregivers were also positive about young children being physically active. Recommendations for potential intervention strategies include a teacher-training component, parent/child activity mornings, and a home-based component for parents/caregivers. Conclusion . The findings suggest that an intervention focussed on increasing physical activity and improving gross motor skills per se is largely not required but that contextually relevant physical activity and gross motor skills may still be useful for promoting healthy weight and a vehicle for engaging with teachers and parents/caregivers for promoting other child outcomes, such as cognitive development., Competing Interests: The authors have no competing interests to declare.

Background: The aetiology of the metabolic syndrome and the inter-relationship between risk factors for this syndrome are poorly understood. The purpose of this investigation was to determine the risk factors for metabolic syndrome and their interactions in a cohort of women with a high prevalence of metabolic syndrome., Materials and Methods: Abdominal and whole body composition (ultrasound and dual-energy X-ray absorptiometry), blood pressure, and cardiometabolic and demographic factors were measured in a cross-sectional study of 702 black African women from Soweto, Johannesburg. Data was analysed using multivariate logistic regression., Results: Metabolic syndrome was present in 49.6% of the study cohort. Logistic regression analysis demonstrated that adiponectin (odds ratio [95% CIs]: 0.84 [0.77, 0.92], p<0.0005) and abdominal subcutaneous fat (0.56 [0.39, 0.79], p = 0.001) reduced metabolic syndrome risk whilst insulin resistance (1.31 [1.16, 1.48], p<0.0005) and trunk fat-free soft-tissue mass (1.34 [1.10, 1.61], p = 0.002) increased risk. Within this group of risk factors, the relationship of adiponectin with metabolic syndrome risk, when analysed across adiponectin hexiles, was the least affected by adjustment for the other risk factors., Conclusions: Adiponectin has a significant protective role against metabolic syndrome and is independent of other risk factors. The protective and possible augmentive effects of abdominal subcutaneous fat and lean trunk mass, respectively on metabolic syndrome risk demonstrate the existence of novel interactions between body composition and cardiometabolic disease., Competing Interests: The authors declare no conflict of interest.

Objectives: Little data are available for sub-Saharan African women on changes in body composition in menopause transition (MT). The study aimed to determine whether there are differences in body adiposity, lean muscle mass, and bone mineral density (BMD) across MT groups in urban African women, who have a high prevalence of obesity and HIV infection, and if this is related to an altered hormonal milieu., Design: Participants were 702 black urban women. Menopause stage was defined using STRAW+10 criteria. Levels of follicle stimulating hormone (FSH), estradiol (E2), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), testosterone (T) and sex hormone blinding globulin (SHBG) were measured. Body composition was measured with dual-energy X-ray absorptiometry (DXA) and ultrasound scans., Results: Whole body lean mass (p=0.002) and BMD (p<0.0005) were significantly lower in postmenopausal compared to premenopausal groups. Estradiol (p<0.0005), SHBG (p<0.0005) and DHEAS (p=0007) were significantly lower in post- than premenopausal groups, while FSH was higher (p<0.0005). FSH correlated negatively (β=-2.06, p<0.0005) with total lean mass while E2 correlated positively (β=20.0, p=0.002) with BMD. Use of antiretroviral therapy (ART) correlated negatively with total fat mass (β=-2.92, p=0.008) and total bone mineral content (BMC; β=-78.8, p=0.003)., Conclusions: The MT in this population is characterized by lower whole body lean mass and BMD in post- compared to premenopausal subjects but there are minimal differences in fat mass. Lower lean mass and BMD were associated with higher FSH and lower E2 serum levels, respectively. Use of ART was associated with lower fat mass and BMC., (Copyright © 2015. Published by Elsevier Inc.)

Background: This study aimed to determine whether lifestyle and psycho-social factors determine changes in body composition over 10 years in a population of black African females with a high prevalence of obesity., Materials and Methods: Data were collected from 430 women at baseline and 10-year follow-up. Dual energy x-ray absorptiometry-derived body fat mass and fat free soft tissue mass, and simple anthropometric measures were taken at both time points. Data on physical activity (PA), diet, smoking, and alcohol intake were collected at baseline. Body size dissatisfaction and body size discrepancy were determined at baseline using the feel minus ideal (FID) index and the perceived minus actual weight status discrepancy score (PAD), respectively., Results: All body composition measurements increased over 10 years (p<0.0005). Two distinct groups of overweight/obese females were identified using PAD and FID: one that was content with their body size and one that wished to be leaner. Vigorous PA at baseline was inversely associated with absolute changes in all measures of adiposity. In subjects who underestimated their body size at baseline (74.0% of the study population) changes in total and peripheral levels of body fat were less than in subjects who correctly identified their body size. In the group that underestimated body size, more women wanted to be leaner than in the group who knew their body size (60.1% vs 47.5%, p<0.05)., Conclusions: Underestimation of body size is common and is associated with a lower gain in total body adiposity and a prevalent desire to lose weight.

Objective: The present paper examines dietary intake and body composition in antiretroviral (ARV)-naïve HIV-positive compared with HIV-negative South African women, as well as the impact of disease severity on these variables., Design: Baseline data from a longitudinal study assessing bone health in HIV-negative and HIV-positive premenopausal South African women over 18 years of age were used. Anthropometry and body composition, measured by dual energy X-ray absorptiometry, were analysed together with dietary intake data assessed using an interviewer-based quantitative FFQ., Setting: Soweto, Johannesburg, South Africa., Subjects: Black, urban South African women were divided into three groups: (i) HIV-negative (HIV-; n 98); (ii) HIV-positive with preserved CD4 counts (HIV+ non-ARV; n 74); and (iii) HIV-positive with low CD4 counts and due to start ARV treatment (HIV+ pre-ARV; n 75)., Results: The prevalence of overweight and obesity was high in this population (59 %). The HIV+ pre-ARV group was lighter and had a lower BMI than the other two groups (all P < 0·001). HIV+ pre-ARV women also had lower fat and lean masses and percentage body fat than their HIV- and HIV+ non-ARV counterparts. After adjustment, there were no differences in macronutrient intakes across study groups; however, fat and sugar intakes were high and consumption of predominantly refined food items was common overall., Conclusion: HIV-associated immunosuppression may be a key determinant of body composition in HIV-positive women. However, in populations with high obesity prevalence, these differences become evident only at advanced stages of infection.

Objectives: To evaluate the associations between birth weight (BW), infancy, and childhood weight gain and adult body composition., Methods: Subjects included participants of five birth cohort studies from low and middle income nations (Brazil, Guatemala, India, Philippines, and South Africa; n = 3432). We modeled adult body composition as a function of BW and conditional weight gain (CW), representing changes in weight trajectory relative to peers, in three age intervals (0-12 months, 12-24 months, 24 months-mid childhood)., Results: In 34 of 36 site- and sex-specific models, regression coefficients associated with BW and CWs were higher for adult fat-free than for fat mass. The strength of coefficients predicting fat-free mass relative to those predicting fat mass was greatest for BW, intermediate for CWs through 24 months, and weaker thereafter. However, because fat masses were smaller and showed larger variances than fat-free masses, weaker relationships with fat mass still yielded modest but significant increases in adult % body fat (PBF). CW at 12 months and mid-childhood tended to be the strongest predictors of PBF, whereas BW was generally the weakest predictor of PBF. For most early growth measures, a 1 SD change predicted less than a 1% change in adult body fat, suggesting that any health impacts of early growth on changes in adult body composition are likely to be small in these cohorts., Conclusions: BW and weight trajectories up to 24 months tend to be more strongly associated with adult fat-free mass than with fat mass, while weight trajectories in mid-childhood predict both fat mass and fat-free mass., (2011 Wiley Periodicals, Inc.)

Unlabelled: We compared whole body BMC of 811 black, white, and mixed ancestral origin children from Detroit, MI; Johannesburg, South Africa; and Cape Town, South Africa. Our findings support the role of genetic and environmental influences in the determination of bone mass in prepubertal children., Introduction: Higher bone mass and lower fracture rates have been shown in black compared with white children and adults in North America., Materials and Methods: We compared whole body BMC (WBBMC), whole body fat mass (WBFM), and whole body fat free soft tissue (WBFFST) data between three ethnic groups of children from Detroit, MI (n = 181 white, USW; n = 230 black, USB), Johannesburg, South Africa (n = 73 white, SAW; n = 263 black, SAB), and Cape Town, South Africa (n = 64 mixed ancestral origin, SAM)., Results: SAB and SAW groups were slightly older than USW and USB groups (9.5 +/- 0.3 versus 9.3 +/- 0.1 yr); however, USB and USW boys were significantly taller, were heavier, and had a higher BMI than SAM and SAB boys. USB girls were significantly taller than SAB girls and heavier than SAB and SAM girls. In South Africa and the United States, black children had a significantly higher WBBMC than white children, after adjusting for selected best predictors. After adjusting for age, weight, and height, WBBMC was significantly higher in the SAB and SAW boys than in USW and USB and in the SAM group compared with the USW and USB groups. WBFFST and WBFM made significant contributions to a best linear model for log(WBBMC), together with age, height, and ethnicity. The best model accounted for 79% of the WBBMC variance. When included separately in the model, the model containing WBFFST accounted for 76%, and the model containing WBFM accounted for 70%, of the variance in WBBMC., Conclusions: WBBMC is lower in children of European ancestry compared with African ancestry, irrespective of geographical location; however, South African children have significantly higher WBBMC compared with USB and USW groups, thereby acknowledging the possible contribution of environmental factors. Reasons for the significantly higher WBBMC in the children of mixed ancestral origin compared with the other groups need to be studied further.

Objective: To determine whether African urban children who were stunted at 2 years of age demonstrated an altered body composition by the end of childhood, before entering puberty, at 9 years of age., Research Methods and Procedures: This was a mixed-longitudinal study of 330 prepubertal African children (182 boys) from Soweto-Johannesburg, South Africa. Anthropometric data at 2 years of age were compared with anthropometric, DXA-determined body composition and fat patterning in late childhood (7 to 9 years)., Results: Children who had been stunted at 2 years were significantly shorter and lighter than non-stunted children at 7 to 9 years, but there were no differences in their BMI or centralization of body fat. Previously stunted status significantly predicted reduced weight and height at 7 to 9 years but did not predict BMI, body composition, or fat patterning after controlling for potential confounding factors. The odds ratio for stunting at 2 years as a predictor of overweight at 7 to 9 years was not significant at 1.09 (95% confidence limits: 0.30, 3.98)., Discussion: Greater BMI in stunted infants does not demonstrate a tendency toward overweight or obesity but is a reflection of the greater reduction in height rather than weight in stunted children. Stunted children may be programmed to accumulate greater body fat at central sites during adolescence, but we have been unable to show that these changes are evident before the initiation of pubertal development.

Background: The regression equations of Slaughter and Dezenberg, which are based on mixed ethnic samples, are currently recommended for predicting body fat from skinfold-thickness measures in prepubescent children of African ancestry. These equations contain methodologic problems that could make them inappropriate for African children., Objective: The objective was to apply the Slaughter and Dezenberg equations to predict body fat in African prepubertal children and to compare the results with body fat measured by dual-energy X-ray absorptiometry (DXA). If significantly different outcomes were observed, then the objective was to develop new prediction equations and validate them on African children., Design: The Slaughter and Dezenberg equations were applied to a cross-sectional sample of 214 prepubescent (Tanner stage 1) African children (118 boys). Body fat was determined by DXA, and subcutaneous fat at triceps, biceps, subscapular, suprailiac, thigh, and calf sites was measured with use of Holtain calipers. A randomly selected sample of 134 participants (78 boys) was used to generate new prediction equations that were validated on the remaining 80 participants (40 boys)., Results: The Slaughter and Dezenberg equations significantly underestimated (P < 0.001) body fat compared with DXA in both boys and girls. The best combination of skinfold thicknesses to predict body fat in African prepubertal boys, controlling for chronologic age, was triceps, biceps, subscapular, suprailiac, and thigh (SEE = 2.87), and for girls it was biceps, subscapular, suprailiac, thigh, and calf (SEE = 3.51)., Conclusion: The Slaughter and Dezenberg equations are unsuitable for predicting body fat in 9-y-old African prepubertal children. New equations that are based on skinfold-thickness combinations from African children provide more accurate estimates.

HIV and severe wasting are associated with post-discharge mortality and hospital readmission among children with complicated severe acute malnutrition (SAM); however, the reasons remain unclear. We assessed body composition at hospital discharge, stratified by HIV and oedema status, in a cohort of children with complicated SAM in three hospitals in Zambia and Zimbabwe. We measured skinfold thicknesses and bioelectrical impedance analysis (BIA) to investigate whether fat and lean mass were independent predictors of time to death or readmission. Cox proportional hazards models were used to estimate the association between death/readmission and discharge body composition. Mixed effects models were fitted to compare longitudinal changes in body composition over 1 year. At discharge, 284 and 546 children had complete BIA and skinfold measurements, respectively. Low discharge lean and peripheral fat mass were independently associated with death/hospital readmission. Each unit Z -score increase in impedance index and triceps skinfolds was associated with 48 % (adjusted hazard ratio 0·52, 95 % CI (0·30, 0·90)) and 17 % (adjusted hazard ratio 0·83, 95 % CI (0·71, 0·96)) lower hazard of death/readmission, respectively. HIV-positive v. HIV-negative children had lower gains in sum of skinfolds (mean difference −1·49, 95 % CI (−2·01, −0·97)) and impedance index Z -scores (–0·13, 95 % CI (−0·24, −0·01)) over 52 weeks. Children with non-oedematous v. oedematous SAM had lower mean changes in the sum of skinfolds (–1·47, 95 % CI (−1·97, −0·97)) and impedance index Z -scores (–0·23, 95 % CI (−0·36, −0·09)). Risk stratification to identify children at risk for mortality or readmission, and interventions to increase lean and peripheral fat mass, should be considered in the post-discharge care of these children. [ABSTRACT FROM AUTHOR]

Objective: Adipose tissue is a central regulator of metabolic health and a contributor to systemic inflammation. Patterns of adiposity deposition are important to understand for optimizing health. This study aimed to asses relationships between adiposity deposition and metabolic and inflammatory biomarkers in South African women prior to conception. Methods: Non‐pregnant, healthy women (n = 298) were recruited for this cross‐sectional study via home visits. Body composition was measured by Dual X‐ray Absorptiometry. Inflammation markers C‐reactive protein (CRP), alpha1‐acid glycoprotein (AGP), hemoglobin A1c (HbA1c), and blood pressure were scored according to risk. A summative metabolic health risk score was created for women with obesity. Generalized regression models assessed relationships between adiposity deposition and outcomes with adjustment for potential confounders. Results: Obesity was present in 22% of women (mean age = 20.93 years). Fat mass index was associated with inflammation and metabolic health risk (β = 0.58; p < 0.01). Visceral fat, trunk:limb ratio, android:gynoid ratio, body mass index, weight, and waist circumference were positively associated with CRP, AGP, and metabolic health risk (p < 0.01). Weight was associated with Hba1c (β < 0.01; p < 0.05). Participants with obesity and low metabolic health risk had lower fat mass index and visceral fat than participants with obesity and higher metabolic health risk. Conclusions: Black South African women accumulated excess adipose tissue in abdominal regions. While fat mass and body mass were associated with inflammation and metabolic health risk, women with obesity and with lower fat mass index and lower visceral adipose tissue were metabolically protected. Identification of women at risk for metabolic disease preconception could help ensure future healthy pregnancies and prevent transference of risk to offspring. [ABSTRACT FROM AUTHOR]

Background: Hyperglycaemia first detected during pregnancy(HFDP) has far-reaching maternal consequences beyond the pregnancy. Our study evaluated the cardiometabolic outcomes in women with prior HFDP versus women without HFDP 3–6 years post-partum in urban South Africa. Design and methods: A prospective cohort study was performed of 103 black African women with prior HFDP and 101 without HFDP, 3–6 years post-partum at Chris Hani Baragwanath Academic Hospital, Soweto. Index pregnancy data was obtained from medical records. Post-partum, participants were re-evaluated for anthropometric measurements, body composition utilizing dual energy X-ray absorptiometry(DXA) and biochemical analysis (two-hour 75gm OGTT fasting insulin, lipids, creatinine levels and glucose levels). Cardiovascular risk was assessed by Framingham risk score(FRS). Carotid intima media thickness(cIMT) was used as a surrogate marker for subclinical atherosclerosis. Factors associated with progression to cardiometabolic outcomes were assessed using multivariable logistic and linear regression models. Results: Forty-six(45.1%) HFDP women progressed to diabetes compared to 5(4.9%) in non HFDP group(p<0.001); only 20(43.4%) were aware of their diabetic status in the whole group. The odds(OR, 95% confidence interval(CI)) of progressing to type 2 diabetes(T2DM) and metabolic syndrome(MetS) after correcting for confounders in the HFDP group was 10.5(95% CI 3.7–29.5) and 6.3(95%CI 2.2–18.1), respectively. All visceral fat indices were found to be significantly higher in the HFDP group after adjusting for baseline body mass index. Ten-year estimated cardiovascular risk(FRS) and mean cIMT was statistically higher in the HFDP group(8.46 IQR 4.9–14.4; 0.48 mm IQR 0.44–0.53 respectively) compared to the non-HFDP group(3.48 IQR 2.1–5.7; 0.46mm IQR 0.42–0.50) respectively and this remained significant for FRS but was attenuated for cIMT after correcting for confounders. HIV did not play a role in progression to any of these outcomes. Conclusion: Women with a history of HFDP have a higher risk of cardiometabolic conditions within 6 years post-partum in an urban sub-Saharan African setting. [ABSTRACT FROM AUTHOR]

Objective: To determine whether food security, diet diversity and diet quality are associated with anthropometric measurements and body composition among women of reproductive age. The association between food security and anaemia prevalence was also tested.Design: Secondary analysis of cross-sectional data from the Healthy Life Trajectories Initiative (HeLTI) study. Food security and dietary data were collected by an interviewer-administered questionnaire. Hb levels were measured using a HemoCue, and anaemia was classified as an altitude-adjusted haemoglobin level < 12·5 g/dl. Body size and composition were assessed using anthropometry and dual-energy x-ray absorptiometry.Setting: The urban township of Soweto, Johannesburg, South Africa.Participants: Non-pregnant women aged 18-25 years (n 1534).Results: Almost half of the women were overweight or obese (44 %), and 9 % were underweight. Almost a third of women were anaemic (30 %). The prevalence rates of anaemia and food insecurity were similar across BMI categories. Food insecure women had the least diverse diets, and food security was negatively associated with diet quality (food security category v. diet quality score: B = -0·35, 95 % CI -0·70, -0·01, P = 0·049). Significant univariate associations were observed between food security and total lean mass. However, there were no associations between food security and body size or composition variables in multivariate models.Conclusions: Our data indicate that food security is an important determinant of diet quality in this urban-poor, highly transitioned setting. Interventions to improve maternal and child nutrition should recognise both food security and the food environment as critical elements within their developmental phases. [ABSTRACT FROM AUTHOR]

Growth in early life is associated with various individual health outcomes in adulthood, but limited research has been done on associations with a more comprehensive measure of health. Combining information from multiple biological systems, allostatic load (AL) provides such a quantitative measure of overall physiological health. We used longitudinal data from the Birth to Twenty Plus cohort in South Africa to calculate an AL score at age 22 years and examined associations with birth weight and linear growth and weight gain from age 0 to 2 years and 2 to 5 years, as attenuated by trajectories of body mass index and pubertal development in later childhood and adolescence. Differences in total AL score between males and females were small, though levels of individual biological factors contributing to AL differed by sex. Increased weight gain from age 2 to 5 years among males was associated with an increased risk of high AL, but no other early-life measures were associated with AL. Increased adiposity through childhood and adolescence in females was associated with higher AL in early adulthood. These results illustrate that patterns of early-life growth are not consistently associated with higher AL. While more research is needed to link AL in young adulthood to later health outcomes, these results also suggest increased adiposity during childhood and adolescence represents a potential early sign of later physiological risk. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus‐ (HIV‐) infection and antiretroviral therapy (ART) exposure are associated with bone loss. African data are limited despite the region's HIV burden. Of 247 ART‐naïve, premenopausal, urban, black African women aged 33.9 ± 6.6 years from Soweto, South Africa, measured at baseline, 110 underwent anthropometry, DXA, and blood and urine collections at 12 and 24 months; 39 were HIV‐negative (Nref), 28 were people with HIV (PWH) not ART‐exposed for the duration of the study (ART‐N), and 43 were PWH who were ART‐exposed within the first 12 months (ART‐Y). At baseline, the ART‐Y group had lower BMI and fat mass than the Nref group. Within 12 months of ART initiation, areal bone mineral density (aBMD) had decreased at the lumbar spine and at the whole body less head, despite increased weight, and hip aBMD had not increased in line with the Nref group. There was no evidence of further bone changes between 12 and 24 months. By 24 months, the ART‐Y women had gained weight and fat mass, but remained lighter with less fat than the Nref women. ART initiation normalized the low serum albumin of the ART‐Y group at baseline, but was associated with elevated bone turnover markers at 12 and 24 months. Vitamin D status and renal phosphate handling were normal. ART‐N had similar aBMD and other characteristics to the Nref group throughout, except unlike the Nref group, weight and fat mass did not increase and serum albumin decreased. This study in African women of childbearing age demonstrated that the bone loss that had occurred in these PWH after ART initiation did not continue after 12 months and that bone loss did not occur in ART‐unexposed PWH over 2 years. At 24 months, despite gains in weight and fat mass, ART‐exposed women remained lighter, with lower aBMD, fat mass, and higher bone turnover than women without HIV. More studies are required to establish if the bone loss and fat gain reverse, stabilize, or continue with further ART exposure, particularly during and after menopause. © 2020 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

The article discusses the associations between maternal Traditional dietary pattern adherence, antiretroviral HIV infection treatment exposure, neonatal size, and adiposity in urban, black South Africans, and it mentions maternal factors such as body mass index and gestational weight gain.

Developing countries are disproportionately affected by hypertension, with Black women being at greater risk, possibly due to differences in body fat distribution. The objectives of this study were: (1) To examine how different measures of body composition are associated with blood pressure (BP) and incident hypertension; (2) to determine the association between baseline or change in body composition, and hypertension; and (3) to determine which body composition measure best predicts hypertension in Black South African women. The sample comprised 478 non-hypertensive women, aged 29–53 years. Body fat and BP were assessed at baseline and 8.3 years later. Body composition was assessed using dual-energy X-ray absorptiometry (DXA) (n = 273) and anthropometry. Hypertension was diagnosed based on a systolic/diastolic BP ≥140/90 mmHg, or medication use at follow-up. All body composition measures increased (p<0.0001) between baseline and follow-up. SBP and DBP increased by ≥20%, resulting in a 57.1% cumulative incidence of hypertension. Both DXA- and anthropometric-derived measures of body composition were significantly associated with BP, explaining 3–5% of the variance. Baseline BP was the most important predictor of hypertension (adjusted OR: 98–123%). Measures of central adiposity were associated with greater odds (50–65%) of hypertension than total adiposity (44–45%). Only change in anthropometric-derived central fat mass predicted hypertension (adjusted OR: 32–40%). This study highlights that body composition is not a major determinant of hypertension in the sample of black African women. DXA measures of body composition do not add to hypertension prediction beyond anthropometry, which is especially relevant for African populations globally, taking into account the severely resource limited setting found in these communities. [ABSTRACT FROM AUTHOR]

Objective: To investigate the associations of household and neighbourhood socio-economic position (SEP) with indicators of both under- and overnutrition in adolescents and to explore sex differences.Design: Analysis of anthropometric, household and neighbourhood SEP data from the Birth to Twenty Plus cohort born in 1990. Anthropometric outcomes were BMI (thinness, overweight and obesity) and percentage body fat (%BF; low, high). Associations between these and the household wealth index, caregiver education and neighbourhood SEP tertile measures were examined using binary logistic regression.Setting: Johannesburg-Soweto, South Africa.Subjects: Adolescents aged 17-19 years (n 2019; 48·2% men).Results: Women had a significantly higher combined prevalence of overweight/obesity (26·2%) than men (8·2%) whereas men had a significantly higher prevalence of thinness than women (22·2% v. 10·6%, respectively). Having a low neighbourhood social support index was associated with higher odds of high %BF in women (OR=1·59; 95% CI 1·03, 2·44). A low household wealth index was associated with lower odds of both overweight (OR=0·31; 95% CI 0·12, 0·76) and high %BF in men (OR=0·28; 95% CI 0·10, 0·78). A low or middle household wealth index was associated with higher odds of being thin in men (OR=1·90; 95% CI 1·09, 3·31 and OR=1·80; 95% CI 1·03, 3·15, respectively). For women, a low household wealth index was associated with lower odds of being thin (OR=0·49; 95% CI 0·25, 0·96).Conclusions: The study highlights that even within a relatively small urban area the nutrition transition manifests itself differently in men and women and across SEP indicators. Understanding the challenges for different sexes at different ages is vital in helping to plan public health services. [ABSTRACT FROM AUTHOR]

Highlights: [ • ] Health inequalities reduce in adolescence compared to childhood in South Africa. [ • ] Biological & socio-economic status factors should be considered to understand change in inequality. [ • ] Obesity prevention in South Africa should target girls whose mothers have a high BMI. [Copyright &y& Elsevier]

Abstract: As the global prevalence of childhood overweight and obesity spreads to low and middle income countries, there is an increasing need for researchers to assess overweight and obesity in populations where child undernutrition still prevails. Although BMI (body mass index) cutoffs are widely used in research and project evaluations, they have only recently been included in WHO definitions for overweight and obesity in children. This review describes the history of how and why BMI was introduced as a proxy for adiposity in children, the scientific evidence and examples from epidemiological studies. Overall, BMI continues to be a valuable measure in children if the underlying assumptions of the criteria and cut-off values are considered. However, where BMI is associated with height, in children, we recommend using weight for height z-scores. [Copyright &y& Elsevier]

ObjectiveAssessment of vitamin D status in a cohort of healthy 10-year-old urban children and the factors that influence vitamin D status in these children.DesignA cross-sectional study. Blood samples were collected across four seasons of the year for the biochemical determination of serum 25-hydroxyvitamin D [25(OH)D]. Anthropometric measurements (height and weight), BMI and total fat and lean mass (determined by the dual energy X-ray absorptiometry) were measured. 25(OH)D concentrations were assessed by chemiluminescent assay.SettingStudy of children in the Greater Johannesburg area of South Africa who form the Bone Health sub-cohort of the longitudinal Birth to Twenty cohort.SubjectsThree hundred and eighty-five children who form the Bone Health sub-cohort of the longitudinal Birth to Twenty cohort.ResultsWhite children had significantly higher 25(OH)D than their black peers (120·0 (sd 36·6) nmol/l v. 93·3 (sd 34·0) nmol/l, respectively). Seasonal variations in 25(OH)D levels were found only in white children, with 25(OH)D levels being significantly higher in white than in black children during the autumn and summer months. In multiple regression analysis, season, ethnicity, sex and total fat mass were the factors found to have an influence on 25(OH)D. Vitamin D deficiency (7 %) and insufficiency (19 %) were uncommon among the 10-year-old children.ConclusionsVitamin D supplementation or fortification is not warranted in healthy children living in Johannesburg. However, further studies need to confirm this in other regions of the country, especially in those living further south and with less sunshine during the winter months. [ABSTRACT FROM AUTHOR]