Independent changes in female body shape with parity and age: A life-history approach to female adiposity

Testosterone mediates life-history trade-offs in female mammals

Hormones mediate life-history trade-offs. In female mammals, such trade-offs have been studied predominantly in the contexts of oestrogen, progesterone and prolactin. We evaluate the hypothesis that prenatal and postnatal testosterone levels structure and regulate trade-offs in females involving components of reproduction and survival. This hypothesis is predicated on the observation that testosterone confers competition-related and survival-related benefits, but also reproduction-related costs, to female mammals. The hypothesis is supported by field and laboratory data from diverse non-human animals, and data from healthy women. Most broadly, relatively low testosterone level in females has been associated with earlier, faster and higher offspring production, greater attractiveness to males, and reduced dominance or competitiveness, whereas higher testosterone level is associated with delayed and reduced reproduction but increased dominance, status, aggression, and resource accrual. The magnitude of testosterone-mediated trade-offs is expected to depend upon the strength of female-female competition, which represents some function of species-specific ecology, behaviour and mating system. Testosterone-associated trade-offs have, until now, been virtually ignored in studies of female life history, reproductive physiology, evolutionary endocrinology, and female-limited disease, probably due to researcher biases towards conceptualizing androgens as hormones with effects mainly restricted to males.

Bright-siding stigma: Older adults' experiences at a higher weight in Atlantic Canada

The lived experiences of higher-weight people vary; homogenous samples may fail to capture this diversity. This study develops an in-depth understanding of the lived experiences of higher-weight (Body Mass Index ⩾ 30) older adults (⩾60 years of age) in a Canadian Atlantic province. Participants (n = 11) were interviewed face-to-face using a semi-structured interview guide twice at 2-to-3-month intervals regarding their perceived treatment in social and health situations; how positive and negative healthcare experiences affected their health, lifestyles and healthcare seeking-behaviour; and recommendations in terms of patient experiences, access and inclusion. Participants infrequently reported negative experiences; however, participants' experiences were informed by uptake of moralistic, neoliberal discourses. Thematic content analysis identified two major themes: active citizenship (participants demonstrated internalisation of the imperative for weight loss, healthy lifestyles and active ageing) and bright-siding (participants expressed that a positive attitude could prevent/help cope with stigma). Results suggest that individualistic, rather than collective, political solutions to health and stigma have been taken up by higher-weight older adults in a Canadian Atlantic province, which may hinder attempts at structural reforms addressing stigma.

The relationship of reproductive factors with adiposity and body shape indices changes overtime: findings from a community-based study

BACKGROUND

Studies focusing on the relationships of adiposity and body shape indices with reproductive factors have reported conflicting results. This study aimed to investigate the influence of reproductive factors on adiposity and body shape indices changes overtime.

MATERIALS AND METHODS

In this community-based prospective study, 1636 postmenopausal women were selected from Tehran Lipid and Glucose Study (TLGS). The unadjusted and adjusted Generalized Estimating Equation models (GEE) were applied to investigate secular longitudinal trends of adiposity and body shape indices.

RESULTS

According to the adjusted GEE models, mean changes in body mass index (BMI) in women with early menarche was 1.18 kg/m² higher than those with normal menarche age (P = 0.030). Moreover, the mean changes in BMI overtime were 0.11 kg/m² higher in women with premature/early menopausal age than those with normal menopausal age (P = 0.012). Mean changes of waist circumference (WC) in women with late menopause were 2.27 cm higher than those with normal menopausal age (P = 0.036). We also observed higher mean changes in a body shape index (ABSI) in women with late menopause (P = 0.037), compared to those with normal menopausal age. We found a marginal effect of parity on BMI and WC as well.

CONCLUSIONS

This study demonstrated higher BMI in females with earlier menarche age. We also showed higher values of BMI overtime in women with premature/ early menopause, whereas women with late menopausal age had higher WC and ABSI values. However, more longitudinal studies investigating body composition indices by adjusting all potential confounders are still required to confirm our study findings.

The Effects of Self-Compassion and Self-Esteem Writing Interventions on Women’s Valuation of Weight Management Goals, Body Appreciation, and Eating Behaviors

In this study, we examined the effects of body-focused daily self-compassion and self-esteem expressive writing activities on women’s valuation of weight management goals, body appreciation, bulimic symptoms, and healthy and unhealthy eating behaviors. One-hundred twenty-six women, recruited from the community and a university participant pool ( Mage = 29.3, SD = 13.6), were randomly allocated to one of the three writing conditions: body-focused self-compassion, body-focused self-esteem, or control. Women reflected on a moment within the past 24 hours that made them feel self-conscious about their bodies, eating, or exercise habits (self-compassion and self-esteem conditions) or on a particular situation or feeling that occurred in the past 24 hours (control condition) for 4–7 days. At post-treatment (24 hours after the intervention), women in the self-compassion group demonstrated decreased bulimic symptoms, while women in the self-esteem and control conditions did not. Furthermore, clinically significant changes in bulimic symptoms were associated with being in the self-compassion condition but not in the self-esteem or control conditions. Results suggest that body-focused writing interventions may be more effective in temporarily reducing eating disorder symptoms in women if they focus on harnessing self-compassion. Additional online materials for this article are available on PWQ ’s website at http://journals.sagepub.com/doi/suppl/10.1177/03616843211013465

Bone density and frame size in adult women: Effects of body size, habitual use, and life history

OBJECTIVE

Bone mineral density (BMD) and frame size are important predictors of future bone health, with smaller frame size and lower BMD associated with higher risk of later fragility fractures. We test the effects of body size, habitual use, and life history on frame size and cortical BMD of the radius and tibia in sample of healthy adult premenopausal women.

METHODS

We used anthropometry and life history data from 123 women (age 18-46) from rural Poland. Standard techniques were used to measure height, weight, and body fat. Life history factors were recorded using surveys. Grip strength was measured as a proxy for habitual activity, wrist breadth for skeletal frame size. Cortical BMD was measured at the one-third distal point of the radius and mid-point of the tibia using quantitative ultrasound (reported as speed of sound, SoS).

RESULTS

Radial SoS was high (mean t-score 3.2 ± 1.6), but tibia SoS was average (mean t-score 0.35 ± 1.17). SoS was not associated with age, although wrist breadth was positively associated with age after adjusting for height. Radius SoS was not associated with measures of body size, habitual use, or life history factors. Wrist breadth was associated with body size (p < .05 for all), lean mass, and grip strength. Tibia SoS was associated with height. Life history factors were not associated with frame size or cortical SoS.

CONCLUSIONS

Habitual use and overall body size are more strongly associated with frame size and cortical SoS than life history factors in this sample of healthy adult women.

Evolutionary Theories and Men's Preferences for Women's Waist-to-Hip Ratio: Which Hypotheses Remain? A Systematic Review

Over the last 25 years, a large amount of research has been dedicated to identifying men's preferences for women's physical features, and the evolutionary benefits associated with such preferences. Today, this area of research generates substantial controversy and criticism. I argue that part of the crisis is due to inaccuracies in the evolutionary hypotheses used in the field. For this review, I focus on the extensive literature regarding men's adaptive preferences for women's waist-to-hip ratio (WHR), which has become a classic example of the just-so storytelling contributing to the general mistrust toward evolutionary explanations of human behavior. The issues in this literature originate in the vagueness and incompleteness of the theorizing of the evolutionary mechanisms leading to mate preferences. Authors seem to have rushed into testing and debating the effects of WHR on women's attractiveness under various conditions and using different stimuli, without first establishing (a) clear definitions of the central evolution concepts (e.g., female mate value is often reduced to an imprecise concept of "health-and-fertility"), and (b) a complete overview of the distinct evolutionary paths potentially at work (e.g., focusing on fecundability while omitting descendants' quality). Unsound theoretical foundations will lead to imprecise predictions which cannot properly be tested, thus ultimately resulting in the premature rejection of an evolutionary explanation to human mate preferences. This paper provides the first comprehensive review of the existing hypotheses on why men's preferences for a certain WHR in women might be adaptive, as well as an analysis of the theoretical credibility of these hypotheses. By dissecting the evolutionary reasoning behind each hypothesis, I show which hypotheses are plausible and which are unfit to account for men's preferences for female WHR. Moreover, the most cited hypotheses (e.g., WHR as a cue of health or fecundity) are found to not necessarily be the ones with the strongest theoretical support, and some promising hypotheses (e.g., WHR as a cue of parity or current pregnancy) have seemingly been mostly overlooked. Finally, I suggest some directions for future studies on human mate choice, to move this evolutionary psychology literature toward a stronger theoretical foundation.

Obesity is not just elevated adiposity, it is also a state of metabolic perturbation

Nettle et al. miss the crucial difference between adaptive models of storing energy and explanations for the pathological metabolic state of obesity. I suggest that the association of food insecurity with obesity in women from industrialized settings is most likely due to reverse causation: Poverty reduces agency to resist obesogenic foods, and this scenario is compounded by perturbations of insulin metabolism stemming from high adiposity and lipogenic diets.

Waist-to-hip ratio, body-mass index, age and number of children in seven traditional societies

It has been suggested that the preference for low WHRs evolved because low WHR provided a cue to female reproductive status and health, and therefore to her reproductive value. The present study aimed to test whether WHR might indeed be a reliable cue to female reproductive history (with lower WHRs indicating lower number of children). Previous studies showed such a relationship for modern and industrialized populations, but it has not been investigated in natural fertility, indigenous, more energy constrained populations facing greater trade-offs in energy allocation than do modern societies. Our sample comprised 925 women aged 13 to 95 years from seven non-industrial societies including tribes from Sub-Saharan Africa (Hadza, Datoga, and Isanzu), Western Siberia (Ob Ugric people: Khanty and Mansi), South America (Tsimane) and South Asia (Minahasans and Sangirese). We demonstrated a culturally stable, significant relationship between number of children and WHR among women, controlling for BMI and age. Based on these data, we suggest that WHR is a reliable cue to female reproductive history, and we discuss our results in the context of previous studies indicating usefulness of WHR as an indicator of health and fertility.

Pregnancy: An Underutilized Window of Opportunity to Improve Long-term Maternal and Infant Health-An Appeal for Continuous Family Care and Interdisciplinary Communication

Physiologic adaptations during pregnancy unmask a woman's predisposition to diseases. Complications are increasingly predicted by first-trimester algorithms, amplify a pre-existing maternal phenotype and accelerate risks for chronic diseases in the offspring up to adulthood (Barker hypothesis). Recent evidence suggests that vice versa, pregnancy diseases also indicate maternal and even grandparent's risks for chronic diseases (reverse Barker hypothesis). Pub-Med and Embase were reviewed for Mesh terms "fetal programming" and "pregnancy complications combined with maternal disease" until January 2017. Studies linking pregnancy complications to future cardiovascular, metabolic, and thrombotic risks for mother and offspring were reviewed. Women with a history of miscarriage, fetal growth restriction, preeclampsia, preterm delivery, obesity, excessive gestational weight gain, gestational diabetes, subfertility, and thrombophilia more frequently demonstrate with echocardiographic abnormalities, higher fasting insulin, deviating lipids or clotting factors and show defective endothelial function. Thrombophilia hints to thrombotic risks in later life. Pregnancy abnormalities correlate with future cardiovascular and metabolic complications and earlier mortality. Conversely, women with a normal pregnancy have lower rates of subsequent diseases than the general female population creating the term: "Pregnancy as a window for future health." Although the placenta works as a gatekeeper, many pregnancy complications may lead to sickness and earlier death in later life when the child becomes an adult. The epigenetic mechanisms and the mismatch between pre- and postnatal life have created the term "fetal origin of adult disease." Up to now, the impact of cardiovascular, metabolic, or thrombotic risk profiles has been investigated separately for mother and child. In this manuscript, we strive to illustrate the consequences for both, fetus and mother within a cohesive perspective and thus try to demonstrate the complex interrelationship of genetics and epigenetics for long-term health of societies and future generations. Maternal-fetal medicine specialists should have a key role in the prevention of non-communicable diseases by implementing a framework for patient consultation and interdisciplinary networks. Health-care providers and policy makers should increasingly invest in a stratified primary prevention and follow-up to reduce the increasing number of manifest cardiovascular and metabolic diseases and to prevent waste of health-care resources.

Body composition-derived BMI cut-offs for overweight and obesity in Indians and Creoles of Mauritius: comparison with Caucasians

BACKGROUND AND AIMS

Global estimates of overweight and obesity prevalence are based on the World Health Organisation (WHO) body mass index (BMI) cut-off values of 25 and 30 kg m-2, respectively. To validate these BMI cut-offs for adiposity in the island population of Mauritius, we assessed the relationship between BMI and measured body fat mass in this population according to gender and ethnicity.

METHODS

In 175 young adult Mauritians (age 20-42 years) belonging to the two main ethnic groups-Indians (South Asian descent) and Creoles (African/Malagasy descent), body weight, height and waist circumference (WC) were measured, total body fat assessed by deuterium oxide (D2O) dilution and trunk (abdominal) fat by segmental bioimpedance analysis.

RESULTS

Compared to body fat% predicted from BMI using Caucasian-based equations, body fat% assessed by D2O dilution in Mauritians was higher by 3-5 units in Indian men and women as well as in Creole women, but not in Creole men. This gender-specific ethnic difference in body composition between Indians and Creoles is reflected in their BMI-Fat% relationships, as well as in their WC-Trunk Fat% relationships. Overall, WHO BMI cut-offs of 25 and 30 kg m-2 for overweight and obesity, respectively, seem valid only for Creole men (~24 and 29.5, respectively), but not for Creole women whose BMI cut-offs are 2-4 units lower (21-22 for overweight; 27-28 for obese) nor for Indian men and women whose BMI cut-offs are 3-4 units lower (21-22 for overweight; 26-27 for obese).

CONCLUSIONS

The use of BMI cut-off points for classifying overweight and obesity need to take into account both ethnicity and gender to avoid gross adiposity status misclassification in this population known to be at high risk for type-2 diabetes and cardiovascular diseases. This is particularly of importance in obesity prevention strategies both in clinical medicine and public health.

Body shape and size in 6-year old children: assessment by three-dimensional photonic scanning

Background:

Body shape and size are typically described using measures such as body mass index (BMI) and waist circumference, which predict disease risks in adults. However, this approach may underestimate the true variability in childhood body shape and size.

Objective:

To use a comprehensive three-dimensional photonic scan approach to describe variation in childhood body shape and size.

Subjects/Methods:

At age 6 years, 3350 children from the population-based 2004 Pelotas birth cohort study were assessed by three-dimensional photonic scanner, traditional anthropometry and dual X-ray absorptiometry. Principal component analysis (PCA) was performed on height and 24 photonic scan variables (circumferences, lengths/widths, volumes and surface areas).

Results:

PCA identified four independent components of children's body shape and size, which we termed: Corpulence, Central:peripheral ratio, Height and arm lengths, and Shoulder diameter. Corpulence showed strong correlations with traditional anthropometric and body composition measures (r>0.90 with weight, BMI, waist circumference and fat mass; r>0.70 with height, lean mass and bone mass); in contrast, the other three components showed weak or moderate correlations with those measures (all r<0.45). There was no sex difference in Corpulence, but boys had higher Central:peripheral ratio, Height and arm lengths and Shoulder diameter values than girls. Furthermore, children with low birth weight had lower Corpulence and Height and arm lengths but higher Central:peripheral ratio and Shoulder diameter than other children. Children from high socio-economic position (SEP) families had higher Corpulence and Height and arm lengths than other children. Finally, white children had higher Corpulence and Central:peripheral ratio than mixed or black children.

Conclusions:

Comprehensive assessment by three-dimensional photonic scanning identified components of childhood body shape and size not captured by traditional anthropometry or body composition measures. Differences in these novel components by sex, birth weight, SEP and skin colour may indicate their potential relevance to disease risks.

Acceptability, Precision and Accuracy of 3D Photonic Scanning for Measurement of Body Shape in a Multi-Ethnic Sample of Children Aged 5-11 Years: The SLIC Study

Background

Information on body size and shape is used to interpret many aspects of physiology, including nutritional status, cardio-metabolic risk and lung function. Such data have traditionally been obtained through manual anthropometry, which becomes time-consuming when many measurements are required. 3D photonic scanning (3D-PS) of body surface topography represents an alternative digital technique, previously applied successfully in large studies of adults. The acceptability, precision and accuracy of 3D-PS in young children have not been assessed.

Methods

We attempted to obtain data on girth, width and depth of the chest and waist, and girth of the knee and calf, manually and by 3D-PS in a multi-ethnic sample of 1484 children aged 5–11 years. The rate of 3D-PS success, and reasons for failure, were documented. Precision and accuracy of 3D-PS were assessed relative to manual measurements using the methods of Bland and Altman.

Results

Manual measurements were successful in all cases. Although 97.4% of children agreed to undergo 3D-PS, successful scans were only obtained in 70.7% of these. Unsuccessful scans were primarily due to body movement, or inability of the software to extract shape outputs. The odds of scan failure, and the underlying reason, differed by age, size and ethnicity. 3D-PS measurements tended to be greater than those obtained manually (p<0.05), however ranking consistency was high (r²>0.90 for most outcomes).

Conclusions

3D-PS is acceptable in children aged ≥5 years, though with current hardware/software, and body movement artefacts, approximately one third of scans may be unsuccessful. The technique had poorer technical success than manual measurements, and had poorer precision when the measurements were viable. Compared to manual measurements, 3D-PS showed modest average biases but acceptable limits of agreement for large surveys, and little evidence that bias varied substantially with size. Most of the issues we identified could be addressed through further technological development.

Translating human biology (introduction to special issue)

OBJECTIVES

Introducing a special issue on "Translating Human Biology," we pose two basic questions: Is human biology addressing the most critical challenges facing our species? How can the processes of translating our science be improved and innovated?

METHODS

We analyze articles published in American Journal of Human Biology from 2004-2013, and find there is very little human biological consideration of issues related to most of the core human challenges such as water, energy, environmental degradation, or conflict. There is some focus on disease, and considerable focus on food/nutrition. We then introduce this special volume with reference to the following articles that provide exemplars for the process of how translation and concern for broader context and impacts can be integrated into research.

CONCLUSIONS

Human biology has significant unmet potential to engage more fully in translation for the public good, through consideration of the topics we focus on, the processes of doing our science, and the way we present our domain expertise.

Parity-related molecular signatures and breast cancer subtypes by estrogen receptor status

INTRODUCTION

Relationships of parity with breast cancer risk are complex. Parity is associated with decreased risk of postmenopausal hormone receptor-positive breast tumors, but may increase risk for basal-like breast cancers and early-onset tumors. Characterizing parity-related gene expression patterns in normal breast and breast tumor tissues may improve understanding of the biological mechanisms underlying this complex pattern of risk.

METHODS

We developed a parity signature by analyzing microRNA microarray data from 130 reduction mammoplasty (RM) patients (54 nulliparous and 76 parous). This parity signature, together with published parity signatures, was evaluated in gene expression data from 150 paired tumors and adjacent benign breast tissues from the Polish Breast Cancer Study, both overall and by tumor estrogen receptor (ER) status.

RESULTS

We identified 251 genes significantly upregulated by parity status in RM patients (parous versus nulliparous; false discovery rate = 0.008), including genes in immune, inflammation and wound response pathways. This parity signature was significantly enriched in normal and tumor tissues of parous breast cancer patients, specifically in ER-positive tumors.

CONCLUSIONS

Our data corroborate epidemiologic data, suggesting that the etiology and pathogenesis of breast cancers vary by ER status, which may have implications for developing prevention strategies for these tumors.

Body composition changes in pregnancy: measurement, predictors and outcomes

Prevalence of overweight and obesity has risen in the United States over the past few decades. Concurrent with this rise in obesity has been an increase in pregravid body mass index and gestational weight gain affecting maternal body composition changes in pregnancy. During pregnancy, many of the assumptions inherent in body composition estimation are violated, particularly the hydration of fat-free mass, and available methods are unable to disentangle maternal composition from fetus and supporting tissues; therefore, estimates of maternal body composition during pregnancy are prone to error. Here we review commonly used and available methods for assessing body composition changes in pregnancy, including: (1) anthropometry, (2) total body water, (3) densitometry, (4) imaging, (5) dual-energy X-ray absorptiometry, (6) bioelectrical impedance and (7) ultrasound. Several of these methods can measure regional changes in adipose tissue; however, most of these methods provide only whole-body estimates of fat and fat-free mass. Consideration is given to factors that may influence changes in maternal body composition, as well as long-term maternal and offspring outcomes. Finally, we provide recommendations for future research in this area.

How do pregnancy-related weight changes and breastfeeding relate to maternal weight and BMI-adjusted waist circumference 7 y after delivery? Results from a path analysis

BACKGROUND

Reproduction has been related to long-term maternal weight gain, and changes in fat mass, with gestational weight gain, have been identified as an important contributor. However, the influence of weight changes during the whole reproductive cycle and the modifying effect of breastfeeding are unknown.

OBJECTIVE

The objective was to examine how prepregnancy weight, gestational weight gain, postpartum weight changes, and breastfeeding influence maternal weight and body mass index-adjusted waist circumference (WCBMI) 7 y after delivery.

DESIGN

This was a prospective cohort study of 23,701 women participating in the Danish National Birth Cohort with singleton births and no births during follow-up. Path analysis was used to assess the total, direct, and indirect effects; the latter was mediated through weight changes on the pathways.

RESULTS

Postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum were highly positively associated with both outcomes. A 1-kg increase in weight retention at 6 mo postpartum corresponded to an average increase of 0.5 kg at 7 y. Gestational weight gain was not associated with WCBMI but was positively associated with weight at 7 y; 87% of this effect was mediated through later weight changes. For both outcomes, a small inverse association was observed for breastfeeding duration. This was strongest for WCBMI, for which 97% of the effect was direct, ie, not mediated through postpartum weight.

CONCLUSIONS

These findings show that postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum contribute equally to adverse maternal anthropometric measures 7 y after delivery. Breastfeeding duration may have a beneficial effect.

Predictors of change in weight and waist circumference: 15-year longitudinal study in Australian adults

BACKGROUND/OBJECTIVES

This study examines which socio-demographic and lifestyle characteristics are associated with weight and waist circumference (WC) change in a cohort of Australian adults over a 15-year period (1992-2007). Further, it tests the effect of period of birth (birth cohort) on mean weight and WC at two time points, 15 years apart.

SUBJECTS/METHODS

Up to three repeated measures of weight (n=1437) and WC (n=1317) were used. Self-reported data on socio-demographic and lifestyle characteristics were derived from repeated questionnaires. Multivariable models, stratified by sex, were adjusted for potential confounders.

RESULTS

Participants born more recently were heavier, on average, than those in the same age group 15 years earlier, but there was no such secular trend in WC. Age at baseline was associated with change in weight and WC, but the pattern was different: participants gained weight up to age 55 years, while WC gain continued to 65 years. In women, higher level of recreational physical activity was associated with lower WC gain (P<0.05). Parity was also associated with WC change in women (P<0.05), but there was no linear trend.

CONCLUSIONS

Age was the most important factor associated with change in weight and WC in both sexes, apparently reducing the influence of all potential covariates. Among women, physical activity and parity were also associated with change in weight and WC. This study provides longitudinal evidence to support public health efforts that address the continuous increases in average weight and WC of many populations around the world.

Volumetric differences in body shape among adults with differing body mass index values: An analysis using three-dimensional body scans

OBJECTIVES

This study quantified differences in body shape of people differing in body mass index (BMI), using three-dimensional (3D) scan-extracted segmental body volumes.

METHODS

Eight segmental volumes were measured on 340 young adults (169 males and 171 females) aged 18-30 years, using the Vitus Smart 3D whole body scanner. Body volumes were also expressed as a ratio of the sex-specific mean volume (segmental or whole body) and compared to BMI using simple linear regression, multiple-segment-linear regression and Lowess curves.

RESULTS

While all segmental volumes increased significantly as BMI increased, the BMI-related patterns of increase varied among different body segments. For example, pelvis and abdomen volumes increased at a significantly greater rate than whole body volume, with the rates of increase greatest in the overweight and obese.

CONCLUSIONS

Body shape changes due to variations in body volume could have important implications in a range of fields that currently use 1D anthropometric measurements that do not capture body shape differences in the same detail.

Linking high parity and maternal and child mortality: what is the impact of lower health services coverage among higher order births?

BACKGROUND

A number of data sets show that high parity births are associated with higher child mortality than low parity births. The reasons for this relationship are not clear. In this paper we investigate whether high parity is associated with lower coverage of key health interventions that might lead to increased mortality.

METHODS

We used DHS data from 10 high fertility countries to examine the relationship between parity and coverage for 8 child health intervention and 9 maternal health interventions. We also used the LiST model to estimate the effect on maternal and child mortality of the lower coverage associated with high parity births.

RESULTS

Our results show a significant relationship between coverage of maternal and child health services and birth order, even when controlling for poverty. The association between coverage and parity for maternal health interventions was more consistently significant across countries all countries, while for child health interventions there were fewer overall significant relationships and more variation both between and within countries. The differences in coverage between children of parity 3 and those of parity 6 are large enough to account for a 12% difference in the under-five mortality rate and a 22% difference in maternal mortality ratio in the countries studied.

CONCLUSIONS

This study shows that coverage of key health interventions is lower for high parity children and the pattern is consistent across countries. This could be a partial explanation for the higher mortality rates associated with high parity. Actions to address this gap could help reduce the higher mortality experienced by high parity birth.

Different associations of subscapular and triceps skinfold thicknesses with pathogen load: an ecogeographical analysis

OBJECTIVES

The dominant evolutionary perspective on adipose tissue has considered it a relatively inert energy store. However, variability in adipose tissue distribution has recently been associated with age, parity, thermal environment and immune function. Genes regulating the innate immune system are more strongly expressed in deep-lying than peripheral adipose tissue. We hypothesized that central adiposity would correlate more strongly than peripheral adiposity with pathogen load across populations.

METHODS

Primary outcomes were subscapular and triceps skinfolds from 133 male and 106 female populations. National values for disability-adjusted life years lost, attributable to infectious diseases, were used to index pathogen load. Linear mixed-effects models were fitted, including a random effect term by country to investigate the association of each skinfold with pathogen load, adjusting for the other skinfold, mean annual temperature and clustering of the populations across countries.

RESULTS

Adjusting for subscapular skinfold, triceps skinfold was not associated with pathogen load in either sex. Adjusting for triceps skinfold, subscapular skinfold was negatively associated with pathogen load in both sexes (P < 0.02). These associations were independent of variability in annual temperature. Adjusting for pathogen load and temperature, Oceanic populations had a different fat distribution compared to other populations.

CONCLUSIONS

Across populations, higher pathogen load was associated with reduced central but not peripheral skinfolds, supporting the hypothesis that central adiposity is more closely associated with immune function. This scenario might explain why some populations increase disproportionately in central adiposity when the environment shifts from low-energy high-pathogen status to high-energy low-pathogen status.

The adolescent transition under energetic stress: Body composition tradeoffs among adolescent women in The Gambia

BACKGROUND AND OBJECTIVES

Life history theory predicts a shift in energy allocation from growth to reproductive function as a consequence of puberty. During adolescence, linear growth tapers off and, in females, ovarian steroid production increases. In this model, acquisition of lean mass is associated with growth while investment in adiposity is associated with reproduction. This study examines the chronological and developmental predictors of energy allocation patterns among adolescent women under conditions of energy constraint.

METHODOLOGY

Fifty post-menarcheal adolescent women between 14 and 20 years old were sampled for weight and body composition at the beginning and end of 1 month in an energy-adequate season and 1 month in the subsequent energy-constrained season in a rural province of The Gambia.

RESULTS

Chronologically and developmentally younger adolescent girls gain weight in the form of lean mass in both energy-adequate and energy-constrained seasons, whereas older adolescents lose lean mass under conditions of energetic stress (generalized estimating equation (GEE) Wald chi-square comparing youngest tertile with older two tertiles 9.750, P = 0.002; GEE Wald chi-square comparing fast- with slow-growing individuals for growth rate 19.806, P < 0.001). When energy is limited, younger adolescents lose and older adolescents maintain fat (GEE Wald chi-square for interaction of age and season 6.568, P = 0.010; GEE Wald chi-square comparing fast- with slow-growing individuals for interaction of growth rate and season 7.807, P = 0.005).

CONCLUSIONS AND IMPLICATIONS

When energy is constrained, the physiology of younger adolescents invests in growth while that of older adolescent females privileges reproductively valuable adipose tissue.

Characteristics of women with body size satisfaction at midlife: results of the Gender and Body Image (GABI) Study

This study characterizes the profile of women (N = 1,789) ages 50 and over who report body size satisfaction on a figure rating scale. Satisfied women (12.2%) had a lower body mass index and reported fewer eating disorder symptoms, dieting behaviors, and weight and appearance dissatisfaction. Interestingly, satisfied women exercised more than dissatisfied women, and weight and shape still played a primary role in their self-evaluation. Weight monitoring and appearance-altering behaviors did not differ between groups. Body satisfaction was associated with better overall functioning. This end point appears to represent effortful body satisfaction rather than passive contentment.

Body dissatisfaction in women across the lifespan: results of the UNC-SELF and Gender and Body Image (GABI) studies

To explore age differences in current and preferred silhouette and body dissatisfaction (current - preferred silhouette discrepancy) in women aged 25-89 years using figural stimuli [range: 1 (very small) to 9 (very large)]. Data were abstracted from two online convenience samples (N = 5868). t-tests with permutation-adjusted p-values examined linear associations between mean silhouette scores (current, preferred, discrepancy score) and age with/without stratification by body mass index (BMI). Modal current silhouette was 5; modal preferred silhouette was 4; mean discrepancy score was 1.8. There was no significant association between current silhouette and age, but a positive linear association between preferred silhouette and age remained after stratification by BMI. A significant inverse linear association of silhouette discrepancy score and age was found only prior to stratification by BMI. Body dissatisfaction exists in women across the adult life span and is influenced by BMI.

A model for estimating body shape biological age based on clinical parameters associated with body composition

BACKGROUND

To date, no studies have attempted to estimate body shape biological age using clinical parameters associated with body composition for the purposes of examining a person's body shape based on their age.

OBJECTIVE

We examined the relations between clinical parameters associated with body composition and chronological age, and proposed a model for estimating the body shape biological age.

METHODS

The study was conducted in 243,778 subjects aged between 20 and 90 years who received a general medical checkup at health promotion centers at university and community hospitals in Korea from 2004 to 2011.

RESULTS

In men, the clinical parameters with the highest correlation to age included the waist- to-hip ratio (r = 0.786, P < 0.001), hip circumference (r = -0.448, P < 0.001), and height (r = -0.377, P < 0.001). In women, the clinical parameters with the highest correlation to age include the waist-to-hip ratio (r = 0.859, P < 0.001), waist circumference (r = 0.580, P < 0.001), and hip circumference (r = 0.520, P < 0.001). To estimate the optimal body shape biological age based on clinical parameters associated with body composition, we performed a multiple regression analysis. In a model estimating the body shape biological age, the coefficient of determination (R(2)) was 0.71 in men and 0.76 in women.

CONCLUSION

Our model for estimating body shape biological age might be a novel approach to variation in body shape that is due to aging. We assume that our estimation model would be used as an adjunctive measure in easily predicting differences in body shape with the use of clinical parameters that are commonly used to assess the status of obesity in a clinical setting.

Marked resistance of femoral adipose tissue blood flow and lipolysis to adrenaline in vivo

AIMS/HYPOTHESIS

Fatty acid entrapment in femoral adipose tissue has been proposed to prevent ectopic fat deposition and visceral fat accumulation, resulting in protection from insulin resistance. Our objective was to test the hypothesis of femoral, compared with abdominal, adipose tissue resistance to adrenergic stimulation in vivo as a possible mechanism.

METHODS

Regional fatty acid trafficking, along with the measurement of adipose tissue blood flow (ATBF) with (133)Xe washout, was studied with the arteriovenous difference technique and stable isotope tracers in healthy volunteers. Adrenergic agonists (isoprenaline, adrenaline [epinephrine]) were infused either locally by microinfusion or systemically. Local microinfusion of adrenoceptor antagonists (propranolol, phentolamine) was used to characterise specific adrenoceptor subtype effects in vivo.

RESULTS

Femoral adipose tissue NEFA release and ATBF were lower during adrenaline stimulation than in abdominal tissue (p < 0.001). Mechanistically, femoral adipose tissue displayed a dominant α-adrenergic response during adrenaline stimulation. The α-adrenoceptor blocker, phentolamine, resulted in the 'disinhibition' of the femoral ATBF response to adrenaline (p < 0.001).

CONCLUSIONS/INTERPRETATION

Fatty acids, once stored in femoral adipose tissue, are not readily released upon adrenergic stimulation. Femoral adipose tissue resistance to adrenaline may contribute to the prevention of ectopic fatty acid deposition.

Ecogeographical associations between climate and human body composition: analyses based on anthropometry and skinfolds

In the 19th century, two "ecogeographical rules" were proposed hypothesizing associations of climate with mammalian body size and proportions. Data on human body weight and relative leg length support these rules; however, it is unknown whether such associations are attributable to lean tissue (the heat-producing component) or fat (energy stores). Data on weight, height, and two skinfold thickness were obtained from the literature for 137 nonindustrialized populations, providing 145 male and 115 female individual samples. A variety of indices of adiposity and lean mass were analyzed. Preliminary analyses indicated secular increases in skinfolds in men but not women, and associations of age and height with lean mass in both sexes. Decreasing annual temperature was associated with increasing body mass index (BMI), and increasing triceps but not subscapular skinfold. After adjusting for skinfolds, decreasing temperature remained associated with increasing BMI. These results indicate that colder environments favor both greater peripheral energy stores, and greater lean mass. Contrasting results for triceps and subscapular skinfolds might be due to adaptive strategies either constraining central adiposity in cold environments to reduce cardiovascular risk, or favoring central adiposity in warmer environments to maintain energetic support of the immune system. Polynesian populations were analyzed separately and contradicted all of the climate trends, indicating support for the hypothesis that they are cold-adapted despite occupying a tropical region. It is unclear whether such associations emerge through natural selection or through trans-generational and life-course plasticity. These findings nevertheless aid understanding of the wide variability in human physique and adiposity.

Associations of birth order with early growth and adolescent height, body composition, and blood pressure: prospective birth cohort from Brazil

Birth weight has been inversely associated with later blood pressure. Firstborns tend to have lower birth weight than their later-born peers, but the long-term consequences remain unclear. The study objective was to investigate differences between firstborn and later-born individuals in early growth patterns, body composition, and blood pressure in Brazilian adolescents. The authors studied 453 adolescents aged 13.3 years from the prospective 1993 Pelotas Birth Cohort. Anthropometry, blood pressure, physical activity by accelerometry, and body composition by deuterium were measured. Firstborns (n = 143) had significantly lower birth weight than later borns (n = 310). At 4 years, firstborns had significantly greater weight and height, indicating a substantial overshoot in catch-up growth. In adolescence, firstborns had significantly greater height and blood pressure and a lower activity level. The difference in systolic blood pressure could be attributed to variability in early growth and that in diastolic blood pressure to reduced physical activity. The magnitude of increased blood pressure is clinically significant; hence, birth order is an important developmental predictor of cardiovascular risk in this population. Firstborns may be more sensitive to environmental factors that promote catch-up growth, and this information could potentially be used in nutritional management to prevent catch-up “overshoot.”

Reproduction, aging, and body shape by three-dimensional photonic scanning in Thai men and women

OBJECTIVES

Aging and reproduction have been independently associated with body shape in women, with redistribution of body fat from lower to upper body regions. This may be interpreted as a life history strategy for allocating energy between competing peripheral fat depots for reproduction, and central fat depots for maintenance and survival. It remains unclear whether men show similar life history strategy in shape. The objectives of this study were to investigate associations between shape, age, and number of offspring in both men and women from Thailand.

METHODS

We analyzed data on body shape from three-dimensional photonic scanning, and number of reported offspring, available for 5,889 men and 6,449 women aged 16-90 years from the Thai National Sizing Survey.

RESULTS

Bearing children was associated with increased upper body girths and decreased lower body girths in women, independent of age, weight and height. Unlike motherhood, fatherhood was not associated with shape outcomes indexing adiposity, but was associated with arm girth, which may represent an index of sexual attractiveness. In those without children, aging was associated with greater upper body girths and reduced lower body girths, in both sexes.

CONCLUSIONS

Life history strategy in body shape is apparent in both sexes, with aging associated with a shift of tissue away from the lower limb to the upper body. Such strategy may reflect age-changes in the relative costs and benefits of different regional tissue masses. Changes in fat distribution related to aging and reproduction may contribute to the life-course development of cardiovascular risk.