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BackgroundSouth Africa's rates of psychiatric morbidity are among the highest in sub-Saharan Africa and are foregrounded by the country's long history of political violence during apartheid. Growing evidence suggests that in utero stress exposure is a potent developmental risk factor for future mental illness risk, yet the extent to which the psychiatric effects of prenatal stress impact the next generation are unknown. We evaluate the intergenerational effects of prenatal stress experienced during apartheid on psychiatric morbidity among children at ages 17-18 and also assess the moderating effects of maternal age, social support, and past household adversity.MethodsParticipants come from Birth-to-Twenty, a longitudinal birth cohort study in Soweto-Johannesburg, South Africa's largest peri-urban township which was the epicentre of violent repression and resistance during the final years of the apartheid regime. Pregnant women were prospectively enrolled in 1990 and completed questionnaires assessing social experiences, and their children's psychiatric morbidity were assessed at ages 17-18.ResultsFull data were available from 304 mother-child pairs in 2007-8. Maternal prenatal stress in 1990 was not directly associated greater psychiatric morbidity during at ages 17-18. Maternal age and past household adversity moderated the intergenerational mental health effects of prenatal stress such that children born to younger mothers and late adolescent/young adult children experiencing greater household adversity exhibited worse psychiatric morbidity at ages 17-18. Social support did not buffer against the long-term psychiatric impacts of prenatal stress.ConclusionsGreater prenatal stress from apartheid predicted adverse psychiatric outcomes among children born to younger mothers and adolescents/young adults who experienced greater concurrent stress. Our findings suggest that prenatal stress may affect adolescent mental health, have stress-sensitising effects, and represent possible intergenerational effects of trauma experienced under apartheid in this sample.

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.

Central Africa is experiencing rapid urbanisation, and this situation comes along with changes in food habits and an increased prevalence of obesity and associated health risks. Factors influencing dietary intake among the diverse African populations are not well understood. Our objective was to characterise the dietary intake and their determinants in the two main ethnic groups experiencing nutrition transition in Cameroon, the Bamiléké and the Béti. We sampled Bamiléké (381) and Béti (347) adults living in both rural and urban, collected socio-demographic variables, assessed dietary patterns by using a food portion photographs book to administrate a FFQ and a 24-h dietary recall technique and derived their BMI from measured weight and height. The dietary patterns of Bamiléké people were composed of more energy-dense foods than the Béti people, regardless of the living area. The energy intake (13·8 (sd 4·6)–15·4 (sd 4·8) MJ v. 9·7 (sd 3·5)–11·2 (sd 3·9 MJ) and the obesity (15–29 % v. 5–8 %) were therefore higher in Bamiléké than in Béti, respectively. Multivariable linear regression analyses showed strong associations of both ethnicities (4·02 MJ; P < 0·001), living area (0·21 MJ; P < 0·001) and education (0·59 MJ; P < 0·048) with energy intake, independently of each other and other socio-demographic factors. The ethnicity factor has been characterised as the more important determinant of diet. Our findings provide new insights and perspectives highlighting the importance of anthropological factors when building prevention campaigns against obesity in Central Africa.

To assess and compare the associations between household socioeconomic (SES) factors with birth outcomes (low birth weight (LBW), small-for-gestational age (SGA) and preterm birth (PTB)) in the Democratic Republic of Congo (DRC) and South Africa (SA). Cross-sectional data of mother-newborn pairs collected in 2017 in the DRC were compared with mother-newborn pairs data from the SA Soweto first 1000-days pregnancy cohort study (2013–2016). Country-specific and pooled multivariable logistic regressions analyses assessed the associations between maternal education, marital status, and housing with LBW, SGA, and PTB adjusted for maternal anthropometry and obstetric factors. 1084 mother-newborn pairs were recruited (DRC: 256; SA: 828). The rates of LBW, PTB and SGA were, 11.5%, 17.1% and 32.8% in the DRC and 15.9%, 10.5% and 20.1% in SA. SES factors differed between countries and sex. In the DRC, being married decreased the odds of having LBW and PTB children by 86% and 80%, respectively. In SA, being a mother with secondary level of education and above was associated with 86% reduced odds of SGA. In the pooled analyses, women with secondary level of education and above had a 2.2-fold increase in odds of giving birth to a PTB newborn. Country of residence and maternal nutritional status were stronger predictors of birth outcomes than SES factors. In sub-Saharan Africa, policies aiming to alleviate women’s education combined with improved social support and household SES prior to and during pregnancy are critical to optimal neonatal outcomes and strategic to achieve the Sustainable Development Goals.

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 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.

Urban populations from highly industrialized countries are characterized by a lower gut bacterial diversity as well as by changes in composition compared to rural populations from less industrialized countries. To unveil the mechanisms and factors leading to this diversity loss, it is necessary to identify the factors associated with urbanization-induced shifts at a smaller geographical scale, especially in less industrialized countries. To do so, we investigated potential associations between a variety of dietary, medical, parasitological and socio-cultural factors and the gut and saliva microbiomes of 147 individuals from three populations along an urbanization gradient in Cameroon. We found that the presence of Entamoeba sp., a commensal gut protozoan, followed by stool consistency, were major determinants of the gut microbiome diversity and composition. Interestingly, urban individuals have retained most of their gut eukaryotic and bacterial diversity despite significant changes in diet compared to the rural areas, suggesting that the loss of bacterial microbiome diversity observed in industrialized areas is likely associated with medication. Finally, we observed a weak positive correlation between the gut and the saliva microbiome diversity and composition, even though the saliva microbiome is mainly shaped by habitat-related factors.

Due to the increasing non-communicable disease burden in Africa, several strategies that target the major lifestyle and physiological risk factors have been implemented to combat such diseases. The Healthy Aging Adult South Africa report card systematically reviews national and regional prevalence data of middle-aged South African adults (45-65 years) published between 2013 and 2020 on diet, physical activity, tobacco use and alcohol consumption, obesity, hypertension, dyslipidaemia and diabetes mellitus. Each indicator was assigned two grades, (1) based on the availability of prevalence data, and (2) based on whether policies have been proposed and implemented for the respective indicators. Alcohol consumption, obesity, hypertension and diabetes received an A grade for the availability of prevalence data. Tobacco use and diet received an A grade for policy and implementation. Gaps have been identified that need to be filled by future research focusing on continued surveillance of all indicators in order to inform and implement effective policies.

Since Myers (1915) coined the term ‘shell shock’ to define the prolonged suffering of soldiers returning from the Great War, the psychological and physical result of distressing experiences, known as trauma, has been of academic interest. Transgenerational transmission of trauma effects has been recorded, demonstrating that on some level, the exposure to trauma of one generation can impact individuals of a subsequent generation (Yehuda & Lehrner, 2018). Observational studies on children of holocaust survivors formed the basis of this trajectory of research (Rakoff, 1966), and eventually this phenomenon became referred to as the transgenerational transmission of trauma (TTT). Since then, TTT has been observed in several contexts, including within families who have experienced high rates historical trauma (O’Neill et al., 2016 ), within regions high-frequencies of historical war and terrorism (Yehuda & Lehrner, 2018) and those who have undergone famine (Ahmed, 2010). This report aims to outline several pathways (biological, psychological, and sociological) by which trauma may be transmitted across generations. Moreover, it discusses several methods of trauma assessment and the related challenges and benefits. Lastly, this report advocates a biopsychosocial approach – an interdisciplinary model using the interplay of biological, psychological, and social-environmental factors – to research TTT. By promoting the benefits of such an interdisciplinary approach we attempt to break up silos between disciplines and encourage collaboration between academics from various backgrounds researching this topic to better serve individuals impacted by TTT.

To assess and compare the associations between household socioeconomic (SES) factors with birth outcomes (low birth weight (LBW), small-for-gestational age (SGA) and preterm birth (PTB)) in the Democratic Republic of Congo (DRC) and South Africa (SA).Cross-sectional data of mother-newborn pairs collected in 2017 in the DRC were compared with mother-newborn pairs data from the SA Soweto first 1000-days pregnancy cohort study (2013-2016). Country-specific and pooled multivariable logistic regressions analyses assessed the associations between maternal education, marital status, and housing with LBW, SGA, and PTB adjusted for maternal anthropometry and obstetric factors.1084 mother-newborn pairs were recruited (DRC: 256; SA: 828). The rates of LBW, PTB and SGA were, 11.5%, 17.1% and 32.8% in the DRC and 15.9%, 10.5% and 20.1% in SA. SES factors differed between countries and sex. In the DRC, being married decreased the odds of having LBW and PTB children by 86% and 80%, respectively. In SA, being a mother with secondary level of education and above was associated with 86% reduced odds of SGA. In the pooled analyses, women with secondary level of education and above had a 2.2-fold increase in odds of giving birth to a PTB newborn. Country of residence and maternal nutritional status were stronger predictors of birth outcomes than SES factors.In sub-Saharan Africa, policies aiming to alleviate women's education combined with improved social support and household SES prior to and during pregnancy are critical to optimal neonatal outcomes and strategic to achieve the Sustainable Development Goals.

BackgroundSouth Africa’s rates of psychiatric morbidity are among the highest in sub-Saharan Africa and are foregrounded by the country’s long history of political violence during apartheid. Recent evidence suggests that maternal trauma during gestation may intergenerationally impact the developing fetus and elevate the future child’s risk for psychiatric disease. We aim to evaluate the intergenerational effects of prenatal stress experienced during apartheid on late adolescent psychiatric morbidity and also assess the potential ameliorative effects of prenatal social support.MethodParticipants (n = 1051) come from Birth-to-Twenty, a longitudinal birth cohort study in Soweto-Johannesburg, South Africa’s largest peri-urban township which was the epicenter of violent repression and resistance during the final years of the apartheid regime. Pregnant women were prospectively enrolled in 1990 and completed questionnaires assessing social experiences, and their children’s psychiatric morbidity were assessed at age 17-18.ResultsFull data were available from 304 mother-child pairs in 2007-8. Pregnant women who experienced worse traumatic stress in 1990 had children who exhibited greater psychiatric morbidity during late adolescence. This relationship was only significant, however, among children born to younger mothers and adolescents who experienced greater concurrent stress. Social support did not buffer the long-term impacts of prenatal stress on future psychiatric morbidity.ConclusionGreater prenatal stress predicted adverse psychiatric outcomes among children born to younger mothers and adolescents who experienced greater concurrent stress. Our findings suggest that prenatal stress may affect adolescent mental health, have stress-sensitizing effects, and represent possible intergenerational effects of trauma experienced under apartheid in this sample.

BackgroundApproximately 14.2% of newborns are estimated to be born low birth weight (LBW) in South Africa. Past work has implicated maternal prenatal stress as a potent predictor of poor birth outcomes, including preterm birth, intrauterine growth restriction, and LBW. However, less is presently known about the impacts of prenatal stress during early gestation in low- and middle-income contexts, where public health burdens due to LBW are much higher.ObjectiveWe assess the effects of psychosocial stress during the first trimester on birthweight in a large sample of women (n = 657) in Soweto, South Africa, a peri-urban township located in the Greater Johannesburg area.MethodsData come from the Soweto First 1000 Days Cohort, a study of maternal and fetal predictors of infant birth outcomes. Multiple regression models were used to examine the impact of prenatal stress on infant birthweight.ResultsThe prevalence of LBW was 16.6%. Adjusting for maternal age, gestational age, fetal gender, body mass index, and parity, maternal prenatal stress during the first trimester was a borderline predictor of lower birthweight in this sample (β = 12.7, p = 0.071, 95% CI [-26.4, 1.10]). Women who reported greater levels of stress appeared to have non-significantly longer gestations, and the negative impact of maternal stress on birthweight only appeared after adjusting for this pattern.ConclusionsThese results suggest that fetal growth restriction associated with first trimester maternal stress may contribute to lower birthweights in this sample. Our findings report modest relationships between maternal stress specific to early gestation as likely important to birth outcomes in this urban South African sample.

Interventions to reduce undernutrition and improve child growth have incorporated improved water, sanitation, and hygiene (WASH) as part of disease transmission prevention strategies. Knowledge gaps still exist, namely, when and which WASH factors are determinants for growth faltering, and when WASH interventions are most effective at improving growth. This study drew cross-sectional data from a longitudinal cohort study and used hierarchical regression analyses to assess associations between WASH factors: water index, sanitation, hygiene index, and growth: height-for-age (HAZ), weight-for-age (WAZ), weight-for-height (WHZ) at 1, 6, and 12 months postpartum among infants a priori born healthy in Soweto, Johannesburg. Household access to sanitation facilities that were not safely managed was associated with a decrease in HAZ scores at 1 month (β = −2.24) and 6 months (β = −0.96); a decrease in WAZ at 1 month (β = −1.21), 6 months (β = −1.57), and 12 months (β = −1.92); and finally, with WHZ scores at 12 months (β = −1.94). Counterintuitively, poorer scores on the hygiene index were associated with an increase at 1 month for both HAZ (β = 0.53) and WAZ (β = 0.44). Provision of safely managed sanitation at household and community levels may be required before improvements in growth-related outcomes are obtained.

Industrialization has impacted the human gut ecosystem, resulting in altered microbiome composition and diversity. Whether bacterial genomes may also adapt to the industrialization of their host populations remains largely unexplored. Here, we investigate the extent to which the rates and targets of horizontal gene transfer (HGT) vary across thousands of bacterial strains from 15 human populations spanning a range of industrialization. We show that HGTs have accumulated in the microbiome over recent host generations and that HGT occurs at high frequency within individuals. Comparison across human populations reveals that industrialized lifestyles are associated with higher HGT rates and that the functions of HGTs are related to the level of host industrialization. Our results suggest that gut bacteria continuously acquire new functionality based on host lifestyle and that high rates of HGT may be a recent development in human history linked to industrialization.

Early-life environmental and nutritional exposures are considered to contribute to the differences in cardiovascular disease (CVD) burden. Among sub-Saharan African populations, the association between markers of early-life exposures such as leg length and sitting height and CVD risk is yet to be investigated. This study assessed the association between leg length, sitting height, and estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk among Ghanaian-born populations in Europe and Ghana. We constructed sex-specific quintiles for sitting height and leg length for 3250 participants aged 40–70 years (mean age 52 years; men 39.6%; women 60.4%) in the cross-sectional multicenter Research on Diabetes and Obesity among African Migrants study. Ten-year risk of ASCVD was estimated using the Pooled Cohort Equations; risk ≥7.5% was defined as “elevated” CVD risk. Prevalence ratios (PR) were estimated to determine the associations between sitting height, leg length, and estimated 10-year ASCVD risk. For both men and women, mean sitting height and leg length were highest in Europe and lowest in rural Ghana. Sitting height was inversely associated with 10-year ASCVD risk among all women (PR for 1 standard deviation increase of sitting height: 0.75; 95% confidence interval: 0.67, 0.85). Among men, an inverse association between sitting height and 10-year ASCVD risk was significant on adjustment for study site, adult, and parental education but attenuated when further adjusted for height. No association was found between leg length and estimated 10-year ASCVD risk. Early-life and childhood exposures that influence sitting height could be the important determinants of ASCVD risk in this adult population.

Associations between different forms of malnutrition and environmental conditions, including water, sanitation and hygiene (WASH), contribute to poor child health, nutritional status and physical growth. The primary responsibility for the provision of water and sanitation, as a basic service and human right, lies with the State, as such, a number of stakeholders are involved. Despite relatively high levels of WASH infrastructure coverage in South Africa, enteric infections and stunting remain high for a middle-income country. The aim of this study is to elucidate the landscape of WASH in South Africa in relation to nutritional status of children under the age of 5 years in the South African, Gauteng and City of Johannesburg contexts. The authors detailed the national and provincial public sector departments and through purposive sampling proceeded to map the various departments and associated policies that are responsible for the provision of WASH facilities, as well the nutritional status of children. Of the six policies identified for review, three mentioned WASH, nutrition and children; however, none explicitly linked WASH to nutritional status in children. An in-depth review and analysis of these three crucial policy documents was conducted. Finally, a set of expert interviews were conducted and a consensus development conference convened, with experts at the intersection between WASH and nutritional status. The authors found that the public sector would benefit from better integration of the concept of WASH into their policy, planning and implementation frameworks. The WASH sector should emphasize the role in which WASH plans consider the impact of WASH on the nutritional status of children. The various public sector departments involved in WASH service provision, and other WASH stakeholders, including community-based organizations, non-governmental organizations and intergovernmental organizations, should be involved in the decision-making of the nutrition sector.

The aim of this study was to identify social and biological drivers of fetal growth by examining associations with household, preconception, and pregnancy factors in a cohort from Soweto, South Africa. Complete data and ultrasound scans were collected on 519 women between 2013 and 2016 at 6 time points during pregnancy (A priori identified exposure variables were then included in a series of sex-stratified hierarchical regression models for each fetal growth outcome. No household-level factors were associated with fetal growth. Maternal BMI at baseline was positively associated with all outcome parameters in males and females. Both GWG (in males and females) and GDM (in males) were significant positive predictors of abdominal growth. Males showed more responsiveness to abdominal growth, while females were more responsive to linear growth. Thus, fetal growth was largely predicted by maternal biological factors, and sexual dimorphism in the responsiveness of fetal biometry to biological exposures was evident.

Horizontal Gene Transfer, the process by which bacteria acquire new genes and functions from non-parental sources, is common in the human microbiome 1,2. If the timescale of HGT is rapid compared to the timescale of human colonization, then it could have the effect of ‘personalizing’ bacterial genomes by providing incoming strains with the genes necessary to adapt to the diet or lifestyle of a new host. The extent to which HGT occurs on the timescale of human colonization, however, remains unclear. Here, we analyzed 6,188 newly isolated and sequenced gut bacteria from 34 individuals in 9 human populations, and show that HGT is more common among bacteria isolated from the same human host, indicating that the timescale of transfer is short compared to the timescale of human colonization. Comparing across 9 human populations reveals that high rates of transfer may be a recent development in human history linked to industrialization and urbanization. In addition, we find that the genes involved in transfer reflect the lifestyle of the human hosts, with elevated transfer of carbohydrate metabolism genes in hunter gatherer populations, and transfer of antibiotic resistance genes among pastoralists who live in close contact with livestock. These results suggest that host-associated bacterial genomes are not static within individuals, but continuously acquire new functionality based on host diet and lifestyle.

Associations between different forms of malnutrition and environmental conditions, including water, sanitation and hygiene (WASH), may contribute towards persistently poor child health, growth and cognitive development. Experiencing poor nutrition in utero or during early childhood is furthermore associated with chronic diseases later in life. The primary responsibility for provision of water and sanitation, as a basic service and human right, lies with the State; however, a number of stakeholders are involved. The situation is most critical in sub-Saharan Africa (SSA), where, in 2015, 311 million people lacked a safe water source, and >70% of SSA populations were living without adequate sanitation. The aim of this paper was to conduct a systematic review to investigate the state of literature concerned with WASH and its association with nutritional status, and governance in children from birth to 5 years of age in SSA. Articles were sourced from PubMed Central, Science Direct and ProQuest Social Science databases published between 1990 and 2017. The PRISMA Statement was utilised and this systematic review is registered with PROSPERO (CRD42017071700). The search terms returned 15,351 articles for screening, with 46 articles included. This is indicative of a limited body of knowledge; however, the number of publications on this topic has been increasing, suggesting burgeoning field of interest. Targeted research on the governance of WASH through the identification of the various role players and stakeholders at various levels, while understanding the policy environment in relation to particular health-related outcomes is imperative to address the burden of child undernutrition.

Approximately 25% of the world's population consists of young people. The experience of violence peaks during adolescence and the early adult years. A link between personal experience of violence and mental health among young people has been demonstrated but rural-urban differences in these associations are less well known in low to middle income countries. The aim of this study was to investigate the associations between interpersonal violence and psychological distress among rural and urban young women.Data on experiences of violence and psychological distress were collected from a total of 926 non-pregnant young women aged between 18 and 22 years of age in rural and urban sites in South Africa. The General Health Questionnaire-28 was used to assess psychological distress as an indicator of mental health. Generalised structural equation models were employed to assess potential pathways of association between interpersonal violence and psychological distress.Thirty-four percent of the urban young women (n = 161) reported psychological distress compared to 18% of rural young women (n = 81). In unadjusted analysis, exposure to interpersonal violence doubled the odds of psychological distress in the urban adolescents and increased the odds 1.6 times in the rural adolescents. In adjusted models, the relationship remained significant in the urban area only (OR 1.84, 95% CI 1.13-3.00). Rural residence seemed protective against psychological distress (OR 0.41, 95% CI 0.24-0.69). Structural equation modelling did not reveal any direct association between exposure to interpersonal violence and psychological distress among rural young women. Stressful household events were indirectly associated with psychological distress, mediated by violence among young women in the urban area.The relationship between violence and psychological distress differs between urban and rural-residing young women in South Africa, and is influenced by individual, household and community (contextual) factors.

Background: The pre-pubertal socioeconomic environment may be an important determinant of age at menarche, adult height, body proportions and adiposity: traits closely linked to adolescent and adult health. Aims: This study explored differences in age at menarche, adult height, relative leg-length and waist circumference between rural and urban black South African young adult women, who are at different stages of the nutrition and epidemiologic transitions. Subjects and methods: We compared 18–23 year-old black South African women, 482 urban-dwelling from Soweto and 509 from the rural Mpumalanga province. Age at menarche, obstetric history and household socio-demographic and economic information were recorded using interview-administered questionnaires. Height, sitting-height, hip and waist circumference were measured using standardised techniques. Results: Urban and rural black South African women differed in their age at menarche (at ages 12.7 and 14.5 years, respectively). In urban women, a one-year increase in age at menarche was associated with a 0.65 cm and 0.16% increase in height and relative leg-length ratio, respectively. In both settings, earlier age at menarche and shorter relative leg-length were independently associated with an increase in waist circumference. Conclusions: In black South African women, the earlier onset of puberty, and consequently an earlier growth cessation process, may lead to central fat mass accumulation in adulthood.

Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms' strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade-off between linear growth and brain growth. Undernutrition in infancy and childhood may trigger adaptive physiological mechanisms prioritizing the brain at the expense of body growth. Another hypothesis is that the period from conception to infancy is a critical window of developmental plasticity of linear growth, the duration of which may vary between and within populations. The transition from infancy to childhood may mark the end of a critical window of opportunity for improving child growth. Both hypotheses emphasize the developmental plasticity of linear growth and the potential determinants of growth variability (including the role of parent-offspring conflict in maternal resources allocation). Implications of these hypotheses in populations with high burdens of undernutrition and infections are discussed. In South Africa, HIV/AIDS during pregnancy (associated with adverse birth outcomes, short duration of breastfeeding, and social consequences) may lead to a shortened window of developmental plasticity of growth. Furthermore, undernutrition and infectious diseases in children living in South Africa, a country undergoing a rapid nutrition transition, may have adverse consequences on individuals' cognitive abilities and risks of cardio-metabolic diseases. Studies are needed to identify physiological mechanisms underlying energy allocation between biological functions and their potential impacts on health.

Adverse birth outcomes and infant undernutrition remain the leading causes of morbidity and mortality in sub-Saharan Africa (SSA). Impaired infant growth and development, which often begins during foetal development, may persist during the first 2 years of life and has been associated with higher risks of cardiometabolic diseases. This systematic review assessed the associations between maternal demographic characteristics and household socio-economic status (SES), and preterm birth (PTB), small for gestational age, low birth weight (LBW), stunting, wasting and underweight in children under 2 years of age in SSA countries. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, we searched for publications in three electronic databases (PubMed, Scopus and ScienceDirect). Eleven studies on children under 2 years of age, in four SSA regions, published in English between 1990 and 2018, were included. All the studies were observational in design (cross-sectional or cohort studies). Maternal education was the most commonly explored exposure. Most studies (63.3%) focused on undernutrition during the first 2 years of life: LBW, PTB and stunting. Lower maternal education, maternal unemployment and lower household wealth index were the SES factors most commonly associated with adverse birth outcomes and infant undernutrition. Maternal marital status was not associated with any infant outcomes. The definitions of the SES varied, which may explain discrepancies between studies. Nutrition intervention programs in SSA need to promote education and poverty alleviation in women at reproductive age, starting from pre-pregnancy, to optimise infant growth and development and prevent the increase in the prevalence of cardiometabolic diseases.

Background: Cardiometabolic disease is associated with chronic low-grade inflammation. While low birthweight, childhood stunting and rapid weight gain predict higher adult high-sensitivity C-reactive protein (hs-CRP) concentrations, associations between childhood infections and adulthood CRP are inconsistent.Aim: To assess the associations between sanitation, diarrhoea and a combined score of both from birth to age 2 years and hs-CRP at age 18 years, independently of early life nutrition and adult adiposity.Subjects and methods: This study collected data on sanitation and diarrhoea episodes from birth to 2 years on 756 participants of the Birth-to-Twenty Plus cohort, a birth cohort initiated in South Africa in 1990, and calculated a combined score of both variables. Anthropometry was measured at 2 years and 18 years and hs-CRP at 18 years.Results: Of the participants, 29.5% had no access to indoor flush sanitation and 38.2% experienced ≥1 diarrhoea episode between birth and 2 years. Not having access to indoor flush sanitation and experiencing ≥1 diarrhoea episodes were associated with 1.50 mg/L and 1.52 mg/L higher hs-CRP, respectively. Prevalence of both burdens in infancy was associated with a 2.18 mg/L higher hs-CRP.Conclusion: In this population, poor sanitation and diarrhoea in early life predict elevated CRP in young adulthood, independently of early life nutrition and adiposity.

ObjectivesVarying 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.SettingRural and urban South Africa.DesignCross-sectional.ParticipantsCross-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.ResultsThe 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).ConclusionsThough 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.

Background:An area of growth in physical activity research has involved investigating effects of physical activity on children’s executive functions. Many of these efforts seek to increase the energy expenditure of young children as a healthy and low-cost way to affect physical, health, and cognitive outcomes.Methods:We review theory and research from neuroscience and evolutionary biology, which suggest that interventions seeking to increase the energy expenditure of young children must also consider the energetic trade-offs that occur to accommodate changing metabolic costs of brain development.Results:According to Life History Theory, and supported by recent evidence, the high relative energy-cost of early brain development requires that other energy-demanding functions of development (ie, physical growth, activity) be curtailed. This is important for interventions seeking to dramatically increase the energy expenditure of young children who have little excess energy available, with potentially negative cognitive consequences. Less energy-demanding physical activities, in contrast, may yield psychosocial and cognitive benefits while not overburdening an underweight child’s already scarce energy supply.Conclusions:While further research is required to establish the extent to which increases in energy-demanding physical activities may compromise or displace energy available for brain development, we argue that action cannot await these findings.

Poor environmental technologies and gastrointestinal illnesses have been hypothesized to be a primary cause to the lack of impact of child health programs on child stunting rates (low height-for-age) in South Africa. This study assessed correlations between environmental exposures (water source, water treatment, sanitation, refuse), diarrheal occurrences, and systemic inflammation proxies among female and male children under five years of age in the Eastern Cape. A conceptual model was hypothesized using structural equation (SE) modeling and two sex-specific (female and male) datasets were subsequently generated from the data and applied to the hypothesized SE model. Results suggested that environmental exposure variables associated with diarrhea and systemic inflammation proxies were different between females and males. For diarrheal occurrences among females, an increase in local authority management of refuse (compared to household management) (0.161, p-value (p) = 0.007), sharing sanitation facilities (0.060, p = 0.023), and a decrease in the frequency of the treatment of drinking water (−0.043, p = 0.025) were correlated with an increase in diarrhea. For males, an increase in household use of flush toilets (as compared to ventilated pit latrines) was correlated with an increase in diarrhea (0.113, p = 0.027). For systemic inflammation among both sexes, an increase in household use of water pumped into the premises (as compared to a public water tap) and an increase in diarrheal occurrences were correlated with an increase in systemic inflammation. The data support an increased focus on sex and gender specific factors among field practitioners and policy makers working in the environmental health field in South Africa.

Socio-economic status (SES) is an important predictor of obesity, but how it is associated with differences in physical activity and sedentary behaviour is less clear. This cross-sectional study examined the association between SES (sum of household assets), physical activity and sedentary time, and how they predict adiposity. Socio-demographic, anthropometric, and physical activity data on rural (n = 509) and urban (n = 510) South African women (18-23 years) were collected. Overweight and obesity prevalence, and sedentary time, were higher; and moderate-vigorous intensity physical activity (MVPA) was lower, in the urban sample. Structural equation models (SEMs) were constructed for BMI and waist circumference. In the urban sample SES had a direct inverse effect on MVPA (beta; 95% CI, -41.69; -73.40 to -9.98), while in the rural sample SES had a direct effect on BMI (beta; 95% CI, 0.306; 0.03 to 0.59). In the pooled sample, SES had a direct inverse effect on MVPA (beta; 95% CI, 144; -170.34 to -119.04), and MVPA was directly associated with BMI (beta; 95% CI, 0.04; 0.01 to 0.08). The influence of SES, and the role of physical activity and sedentary time on adiposity differs between the urban and rural samples, and the importance of other environmental and behavioural factors must be considered in the development of obesity and the design of effective interventions.

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

The persistence of food insecurity, malnutrition, increasing adiposity, and decreasing physical activity, heightens the need to understand relationships between body image satisfaction, eating attitudes, BMI and physical activity levels in South Africa. Females aged 18-23 years were recruited from rural (n = 509) and urban (n = 510) settings. Body image satisfaction was measured using Stunkard's silhouettes, and the 26-item Eating Attitudes questionnaire (EAT-26) was used to evaluate participants' risk of disordered eating. Minutes per week of moderate to vigorous physical activity (MVPA) was assessed using the Global Physical Activity Questionnaire (GPAQ). Significant linear correlates were included in a series of regressions run separately for urban and rural participants. Structural equation modeling (SEM) was used to test the relationships between variables. Urban females were more likely to be overweight and obese than rural females (p = 0.02), and had a greater desire to be thinner (p = 0.02). In both groups, being overweight or obese was positively associated with a desire to be thinner (p

The aims of this paper were to: (1) review the literature and examine contemporary child growth in terms of stunting prevalence across Africa; (2) discuss child stunting within the context of economic growth and adult obesity, and (3) elucidate the implications for child nutrition. It is evident that stunting in under-5-year-old children still plagues Africa and has not decreased as expected in line with the concomitant improvement in economic development over the past decade. Persisting and possibly widening inequality ensures that not all segments of the population, in particular the most vulnerable, benefit equally from economic growth. Of concern is the association between the increasing economic progress across Africa and the rising adult obesity, especially amongst females. More and more African countries are now afflicted with a double burden of malnutrition. The implication for child nutrition is that African countries need not only apply a multisectoral approach to accelerate the reduction in stunting levels, but also to arrest and prevent obesity.

Owing to nutritional transition in Cameroon, one in two adults is overweight and one in five is obese, and 8·1 % of children are overweight and 2·1 % are obese. Given this phenomenon, dietary intake assessment is needed to establish appropriate preventive nutrition-sensitive strategies. Our aim was to develop and test the validity of two food portion photograph books (FPPB) to be used as visual aids for adults and children taking part in a 24-h dietary recall. To design FPPB, interviews and focus group discussions were undertaken with women to obtain consensus on the local categorisation of foods. For each cooked and weighed food, three photographs of the average small, medium and large serving portion sizes were taken, and four intermediary portion sizes were calculated. To validate the FPPB, a sample of adults (361) and children (224) were asked, at meal times, to self-serve a food portion prepared in the household and the portion sizes were weighed; 24 h after the measurement, the same subjects were shown the appropriate FPPB and were asked to indicate the food and the portion they consumed. In adults, of the 821 portions tested, 77 % were accurately estimated, whereas in children 74 % of the 556 portions tested were accurately estimated. For both groups, the small- and medium-sized portions were frequently selected and accurately estimated (>70 %). Our findings suggest that the adult and children’s FPPB can be used in Cameroon to estimate food portion sizes, and thus nutritional intake in the frame of the 24-h dietary recall.

Nutrition transition in developing countries has been associated with higher prevalence of overweight.The study aimed to identify the factors associated with concurrent stunting and overweight in urban preschool children of Yaounde, Cameroon.169 preschool children of both sexes were recruited according to their nutritional status: Stunted, overweight, stunted-overweight, and non-stunted-non-overweight. Factors associated with concurrent stunting and overweight were investigated through interviewer-administered questionnaires. A binary logistic regression model was used to determine the relation between nutritional statuses and associated factors.A low-income family and a low maternal educational level are independent risk factors for a child to be stunted-overweight [odds ratios (95% CI): 3.81 (13.32-1.08), 2.90 (7.82-1.07), respectively]. Mother under-evaluation of child's weight is a factor associated with stunting-overweight and overweight in children [odds ratios (95% CI): 3.42 (8.72-1.33), 6.52 (18.09-2.34), respectively]. Being overweight is also related to higher birth weight. Unlike stunted children, stunted-overweight children live with both their parents and have an older mother. Short maternal stature and mother's over-evaluation of her child's height are independent factors associated with stunting.Poor preschool children of Yaounde are facing concomitant stunting and overweight. More studies are needed to better assess the impact of maternal factors.

Background In the last 20 years, South Africa has experienced political, economic, and demographic transitions accompanied by an epidemiological transition. Like several sub-Saharan countries, the South African population is facing both under–and over–nutrition, and nutrition and lifestyle related chronic disease while the burden of infectious disease remains high. It is critical to understand these trends overtime in order to highlights the pitfalls and successful measures initiatives taken in the efforts to tackle malnutrition. The objective of this systematic review is to investigate the changes in the prevalence of stunting, a chronic form of undernutrition, in South Africa over 40 years, and to derive lessons from the South African experience, a country in an advanced process of transition in sub-Saharan Africa. Methods We undertook a systematic review of publications selected from PubMed, Science Direct and Scopus. We included studies and surveys published between 1970 and 2013 if they reported the prevalence of stunting (low height-for-age) in children under-6 years of age living in South Africa. We excluded studies conducted in health facility outpatients or hospital wards, or children with known chronic and acute infectious diseases. We extracted Date of data collection, study setting, ethnicity, age, sex, sample size, growth references/standards, diagnostic criteria for stunting and prevalence of stunting from each study. Results Over the last decade, the national prevalence of stunting has decreased. However, between and within provincial, age and ethnic group disparities remain. Unlike other countries in sub-Saharan Africa, no sex or rural/urban differences were found in preschool children. However, the analysis of long-term trends and identification of vulnerable groups is complicated by the use of different growth references/standards and sampling methods. Conclusion Despite economic growth, political and social transitions, and national nutritional programs, stunting remains stubbornly persistent and prevalent in South Africa. A multi-sectoral and public health approach is needed to: (i) better monitor stunting over time, (ii) combat malnutrition during the first thousand days of life through continued efforts to improve maternal nutrition during pregnancy and infant feeding practices. Electronic supplementary material The online version of this article (doi:10.1186/s12889-015-1844-9) contains supplementary material, which is available to authorized users.

Early life is important for later health outcomes, yet there are few studies which adequately address all of the potential early life insults that may affect later life health and growth trajectories. This is particularly evident in low- to middle-income countries such as South Africa, where women of childbearing age are particularly vulnerable to high levels of physical inactivity, malnutrition, and obesity. Pregnancy may therefore be an opportune time to change behaviours and improve maternal and offspring health outcomes, and decrease the inter-generational transfer of risk. We show clear evidence that physical activity and nutrition are important target areas for intervention during pregnancy and in the early years of life, yet that current literature in Africa, and specifically South Africa, is limited. We have outlined the available literature concerning the impact of maternal and early life nutrition and physical activity on the health status of South African children, and have provided some recommendations for future research and policy.

Background Recent studies suggest that early modifications in metabolic pathways and behaviour, leading to energy conservation and reduced linear growth, could represent adaptations to nutritional constraints during foetal life and infancy. Impaired fat oxidation, low resting energy expenditure and reduced physical activity, resulting from these adaptations, could facilitate fat storage and development of overweight in growth-retarded children that consume more energy-dense food. This study aims at assessing whether: (1) dual-burden preschool children (simultaneously stunted and overweight) of Yaounde (Cameroon) have low birth-weight (indicator of foetal undernutrition) and reductions in fat oxidation, resting energy expenditure (REE) and physical activity, (2) fat oxidation, REE and physical activity are associated with foetal growth. Methodology/Principal Findings 162 children (24–72 months) were considered: 22 stunted-overweight (SO), 40 stunted (S), 41 overweight (O), and 59 non stunted-non overweight (NSNO). Nutritional status and body composition were assessed using anthropometry and multifrequency bioimpedance analysis. Fasting respiratory quotient (RQ) and REE were measured by indirect calorimetry. Physical activity was determined using accelerometers, food questionnaires were used for diet assessment and birth-weight was noted. Mean RQs and REE (weight adjusted) did not differ between stunted children (SO and S) and non-stunted children (O and NSNO). SO and S children spent more time in sedentary activities than O children (p = 0.01 and p = 0.02, respectively) and less time in moderate-to-vigorous activities than NSNO children (p = 0.05 and p = 0.04, respectively). SO children’s diet was less diverse (p = 0.01) with less animal products (p = 0.006). Multiple linear regressions model revealed that birth-weight is predictive of RQ (β = 0.237, p

Background The social valorisation of overweight in African populations could promote high-risk eating behaviours and therefore become a risk factor of obesity. However, existing scales to assess body image are usually not accurate enough to allow comparative studies of body weight perception in different African populations. This study aimed to develop and validate the Body Size Scale (BSS) to estimate African body weight perception. Methods Anthropometric measures of 80 Cameroonians and 81 Senegalese were used to evaluate three criteria of adiposity: body mass index (BMI), overall percentage of fat, and endomorphy (fat component of the somatotype). To develop the BSS, the participants were photographed in full face and profile positions. Models were selected for their representativeness of the wide variability in adiposity with a progressive increase along the scale. Then, for the validation protocol, participants self-administered the BSS to assess self-perceived current body size (CBS), desired body size (DBS) and provide a “body self-satisfaction index.” This protocol included construct validity, test-retest reliability and convergent validity and was carried out with three independent samples of respectively 201, 103 and 1115 Cameroonians. Results The BSS comprises two sex-specific scales of photos of 9 models each, and ordered by increasing adiposity. Most participants were able to correctly order the BSS by increasing adiposity, using three different words to define body size. Test-retest reliability was consistent in estimating CBS, DBS and the “body self-satisfaction index.” The CBS was highly correlated to the objective BMI, and two different indexes assessed with the BSS were consistent with declarations obtained in interviews. Conclusion The BSS is the first scale with photos of real African models taken in both full face and profile and representing a wide and representative variability in adiposity. The validation protocol proved its reliability for estimating body weight perception in Africans.