Changes in body fat distribution in relation to parity in American women: a covert form of maternal depletion

Is the endotoxin-complement cascade the major driver in lipedema?

Lipedema is a poorly understood disorder of adipose tissue characterized by abnormal but symmetrical deposition of subcutaneous white adipose tissue (WAT) in proximal extremities. Here, we propose that the underlying cause for lipedema could be triggered by a selective accumulation of bacterial lipopolysaccharides (LPS; also known as endotoxin) in gluteofemoral WAT. Together with a malfunctioning complement system, this induces low-grade inflammation in the depot and raises its uncontrollable expansion. Correspondingly, more attention should be paid in future research to the endotoxemia prevalent in patients with lipedema. We would like to propose that proper management of endotoxemia can reduce the progression and even improve the state of disease in patients with lipedema.

Pregnancy as a window of opportunity for dementia prevention: a narrative review

Dementia is a debilitating condition with a disproportionate impact on women. While sex differences in longevity contribute to the disparity, the role of the female sex as a biological variable in disease progression is not yet fully elucidated. Metabolic dysfunctions are drivers of dementia etiology, and cardiometabolic diseases are among the most influential modifiable risk factors. Pregnancy is a time of enhanced vulnerability for metabolic disorders. Many dementia risk factors, such as hypertension or blood glucose dysregulation, often emerge for the first time in pregnancy. While such cardiometabolic complications in pregnancy pose a risk to the health trajectory of a woman, increasing her odds of developing type 2 diabetes or chronic hypertension, it is not fully understood how this relates to her risk for dementia. Furthermore, structural and functional changes in the maternal brain have been reported during pregnancy suggesting it is a time of neuroplasticity for the mother. Therefore, pregnancy may be a window of opportunity to optimize metabolic health and support the maternal brain. Healthy dietary patterns are known to reduce the risk of cardiometabolic diseases and have been linked to dementia prevention, yet interventions targeting cognitive function in late life have largely been unsuccessful. Earlier interventions are needed to address the underlying metabolic dysfunctions and potentially reduce the risk of dementia, and pregnancy offers an ideal opportunity to intervene. This review discusses current evidence regarding maternal brain health and the potential window of opportunity in pregnancy to use diet to address neurological health disparities for women.

Influence of the different hormonal status changes during their life on fat mass localisation in women: a narrative review

CONTEXT

Independently of the total body fat mass, upper body fat mass deposition is strongly associated with cardiometabolic comorbidities. The mechanisms underlying fat mass localisation are not fully understood, but evidences indicate sex-specific fat mass distribution. Currently, data on women are scarce and the link between hormonal status changes during their life and fat mass distribution is overlooked.

METHOD

For this narrative review, literature data were extracted from the PubMed and CENTRAL databases to examine the relationship between hormonal status and adipose tissue localisation in women.

RESULTS

Menopause strongly influences fat mass localisation, while the effect of the menstrual cycle phases, oral contraception use and pregnancy has not been unambiguously determined.

CONCLUSION

Reliable data are lacking on the relationship between hormonal variations throughout the lifespan and body fat mass localisation in women. Future studies should take into account the hormonal status of women to reduce the risk of cardiometabolic diseases.

Tendencies Toward Supernormality/Subnormality in Generating Attractive and Unattractive Female and Male Avatars: Gender Differences

In the present study, we investigated the differences in the experience of attractiveness and unattractiveness of human bodies. A total of 101 participants (55 females) were asked to create the most attractive and the most unattractive female and male figures using a computer animation. They performed this task by adjusting the size of six body parts: shoulders, breasts/chest, waist, hips, buttocks, and legs. Analyses indicated that attractive body parts were distributed normally with the peak shifted to moderately supernormal sizes, while unattractive body parts had mostly U-shaped or skewed distributions with extremes in super-supernormal and/or subnormal sizes. Generally, both male and female attractive bodies had prominent "sporty" look: supernormally wide shoulders and long legs. Gender differences showed that men prefer more supernomal masculine and feminine sizes, while women show an ambivalence toward both groups of traits. Principal components analysis revealed gender differences on the multitrait level: males focus on prominent masculine and feminine traits, while women focus on traits that make both male and female bodies more elongated and slender. Gender differences were in line with specific male and female positions in the partner selection process, while a certain tendency toward masculinization of the female body required the inclusion of social factors, such as the influence of the culture of a sporty and fit look.

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.

High Urban-Rural Inequities of Abdominal Obesity in Malawi: Insights from the 2009 and 2017 Malawi Noncommunicable Disease Risk Factors Surveys

Geographical disparities in abdominal obesity (AO) exist in low-income countries due to major demographic and structural changes in urban and rural areas. We aimed to investigate differences in the urban-rural prevalence of AO in the Malawi population between 2009 and 2017. We conducted a secondary analysis of data from the Malawi 2009 and 2017 STEPS surveys. AO (primary outcome) and very high waist circumference (secondary outcome) were defined using WHO criteria. Prevalence estimates of AO and very high waist circumference (WC) were standardized by age and sex using the age and sex structure of the adult population in Malawi provided by the 2018 census. A modified Poisson regression analysis adjusted for sociodemographic covariates was performed to compare the outcomes between the two groups (urban versus rural). In total, 4708 adults in 2009 and 3054 adults in 2017 aged 25-64 were included in the study. In 2009, the age-sex standardized prevalence of AO was higher in urban than rural areas (40.9% vs 22.0%; adjusted prevalence ratio [aPR], 1.51; 95% confidence interval [CI], 1.36-1.67; p < 0.001). There was no significant trend for closing this gap in 2017 (urban 37.0% and rural 21.4%; aPR, 1.48; 95% CI, 1.23-1.77; p < 0.001). This urban-rural gap remained and was slightly wider when considering the 'very high WC' threshold in 2009 (17.0% vs. 7.1%; aPR, 1.98; 95%CI, 1.58-2.47; p < 0.001); and in 2017 (21.4% vs. 8.3%; aPR, 2.03; 95%CI, 1.56-2.62; p < 0.001). Significant urban-rural differences exist in the prevalence of AO and very high WC in Malawi, and the gap has not improved over the last eight years. More effective weight management strategies should be promoted to reduce health care disparities in Malawi, particularly in urban areas.

Substantial but Misunderstood Human Sexual Dimorphism Results Mainly From Sexual Selection on Males and Natural Selection on Females

Human sexual dimorphism has been widely misunderstood. A large literature has underestimated the effect of differences in body composition and the role of male contest competition for mates. It is often assumed that sexually dimorphic traits reflect a history of sexual selection, but natural selection frequently builds different phenotypes in males and females. The relatively small sex difference in stature (∼7%) and its decrease during human evolution have been widely presumed to indicate decreased male contest competition for mates. However, females likely increased in stature relative to males in order to successfully deliver large-brained neonates through a bipedally-adapted pelvis. Despite the relatively small differences in stature and body mass (∼16%), there are marked sex differences in body composition. Across multiple samples from groups with different nutrition, males typically have 36% more lean body mass, 65% more muscle mass, and 72% more arm muscle than women, yielding parallel sex differences in strength. These sex differences in muscle and strength are comparable to those seen in primates where sexual selection, arising from aggressive male mating competition, has produced high levels of dimorphism. Body fat percentage shows a reverse pattern, with females having ∼1.6 times more than males and depositing that fat in different body regions than males. We argue that these sex differences in adipose arise mainly from natural selection on women to accumulate neurodevelopmental resources.

Serum visfatin as a metabolic biomarker in obese patients with gestational diabetes mellitus

BACKGROUND

Visfatin is an adipokine produced and secreted by the adipose tissue. It exerts an insulin-like effect by the insulin receptor-1 and has a hypoglycemic effect. We aimed to investigate how serum visfatin changes in women with gestational diabetes mellitus (GDM), and whether it is predictive of neonatal outcomes.

METHODS

Visfatin levels were prospectively measured in peripheral blood serum by enzyme immunoassay in 210 pregnant women, 156 of which were diagnosed with GDM, 18 of which suffered from pregnancy-induced hypertension (PIH) and 36 healthy controls.

RESULTS

Patients with obesity class II (median=2.562 ng/mL) and class III (median=6.2940 ng/mL) had higher serum visfatin than overweight patients (median=0.735 ng/mL); (Mann-Whitney U test, P=0.037 and P=0.023, respectively). In GDM patients with BMI above 30, serum visfatin was associated to glycosylated hemoglobin (Spearman correlation test, R=0.26, P=0.045). Women with BMI above 25 treated with insulin had lower serum visfatin levels than those treated with diet only (Mann-Whitney U test, P=0.045). No correlation was found between visfatin and parameters of lipid profile such as HDL, LDL, or triglycerides (Spearman correlation tests, R=-0.051, -0.1, 0.0019; P=0.54, 0.29, 0.98, respectively). We observed that visfatin was not associated with birth weight (Spearman correlation test, R=-0.014, P=0.86) or adverse neonatal outcome as measured by umbilical artery pH below 7.25 (Mann-Whitney U test, P=0.55) or Apgar score below 10 (Mann-Whitney U test, P=0.21).

CONCLUSIONS

In GDM patients with higher BMI, serum visfatin was elevated, correlated positively with glycosylated hemoglobin, and decreased upon treatment with insulin therapy.

Weight Location Moderates Weight-Based Self-Devaluation and Perceived Social Devaluation in Women

Overweight and obese (“heavyweight”) people devalue themselves because, it has been proposed, they are socially devalued. However, for women, social valuation depends not only on how much weight they carry but also on where on their bodies they carry it. Here, we investigated whether weight-based self-valuation and perceived social valuation similarly depend on body shape. Study 1, using a nationally representative sample from National Health and Nutrition Examination Survey (NHANES; N = 1,093 reproductive-aged women), showed that, controlling for body fat, weight labeling (by self and others) and wanting to lose weight depended on body shape. Study 2, in a direct test of predictions using an undergraduate sample of women ( N = 215), showed that with increased body fat, women with an abdominal weight distribution reported more self-devaluation (e.g., lower self-esteem) and perceived social devaluation (e.g., higher perceived weight discrimination); women with a gluteofemoral weight distribution, however, were shielded—partially or fully—from these adverse effects of increased body fat.

Sex differences in white adipose tissue expansion: emerging molecular mechanisms

The escalating prevalence of individuals becoming overweight and obese is a rapidly rising global health problem, placing an enormous burden on health and economic systems worldwide. Whilst obesity has well described lifestyle drivers, there is also a significant and poorly understood component that is regulated by genetics. Furthermore, there is clear evidence for sexual dimorphism in obesity, where overall risk, degree, subtype and potential complications arising from obesity all differ between males and females. The molecular mechanisms that dictate these sex differences remain mostly uncharacterised. Many studies have demonstrated that this dimorphism is unable to be solely explained by changes in hormones and their nuclear receptors alone, and instead manifests from coordinated and highly regulated gene networks, both during development and throughout life. As we acquire more knowledge in this area from approaches such as large-scale genomic association studies, the more we appreciate the true complexity and heterogeneity of obesity. Nevertheless, over the past two decades, researchers have made enormous progress in this field, and some consistent and robust mechanisms continue to be established. In this review, we will discuss some of the proposed mechanisms underlying sexual dimorphism in obesity, and discuss some of the key regulators that influence this phenomenon.

Frailty in ethnic minority women

In majority populations in high- and middle-income countries, women live longer yet experience higher levels of frailty than men of the same age. It is unclear whether this 'sex-frailty paradox' is present in ethnic minority populations. In this narrative review, we explore biological, behavioural and social factors associated with mortality, morbidity and frailty in women, particularly ethnic minority women. We ascertain that natural menopause occurs earlier in women of particular ethnicities. Ethnic minority women (living in high-income countries) have more children and higher rates of chronic disease and disability, all of which are associated with frailty. In some ethnic minorities, women are less likely to engage in deleterious health behaviours such as smoking and alcohol consumption. However, in others the reverse is true. Women from migrant ethnic minorities tend to have lower levels of physical activity. With time, they can also adopt adverse behavioural patterns of the majority population. Although the evidence is sparse, sex differences in health reporting and social assets, as well as gender roles, are likely to contribute to sex differences in frailty in ethnic minorities. Overall, ethnic minority women are a particularly vulnerable group, but the majority of risk factors for frailty appear to be mutable rather than fixed. Future research may examine interventions that target frailty in different races and ethnicities at individual, population and global levels.

Social position and anthropometric status among adults in the ELSA-Brasil study: a latent class analysis

The objective of the present study was to evaluate the association between social position and anthropometric status in women and men Brazilian adult. This was a cross-sectional study that used baseline data collected from 2008 to 2010 for the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil, in Portuguese), in the six major Brazilian state capital cities. A total of 15,105 active and retired civil servants aged from 35 to 74 years. Two latent variables were defined by latent class analysis, social position and anthropometric status. Both constructs and the analyses were separately evaluated by sex. Associations were assessed using multivariate logistic regression analysis with adjustment for age, self-reported skin color/race, and marital status. Around 44% of the women and 26% of the men were classified as overweight or obese. Social position tended to be lower in women (43.2%) and higher among men (40.4%). Heavier women were more likely to be black and brown-skinned, whereas slimmer women were more likely to be white. After adjustment, women's weight increased as social position decreased (OR = 1.52; 95%CI: 1.36-1.70), whereas in men weight decreased as social position decreased (OR = 0.87; 95%CI: 0.76-0.99). Social position affected the anthropometric status of women and men differently, with body patterns also being affected by ethnicity/skin color, showing the potentiality of taking the intersectional perspective when investigating the possible social determinants of the phenomenon.

Sex differences in adipose development in a hunter-gatherer population

OBJECTIVE

Humans are unusually sexually dimorphic in body composition, with adult females having on average nearly twice the fat mass as males. The development of adipose sex differences has been well characterized for children growing up in food-abundant environments, with less known about cross-cultural variation, particularly in populations without exposure to market foods, mechanized technologies, schooling, vaccination, or other medical interventions.

METHODS

To add to the existing cross-cultural data, we fit multiple growth curves to body composition and anthropometric data to describe adipose development for the Savanna Pumé, South American hunter-gatherers.

RESULTS

(1) Little evidence is found for an adiposity 'rebound' at the end of early childhood among either Savanna Pumé girls or boys. (2) Rather, fat deposition fluctuates during childhood, from age ~4 to ~9 years, with no appreciable accumulation until the onset of puberty, a pattern also observed among Congo Baka hunter-gatherers. (3) Body fat fluctuations are more pronounced for girls than boys. (4) The age of peak skeletal, weight, and adipose gains are staggered to a much greater extent among the Savanna Pumé compared to the National Health and Nutrition Examination Survey (NHANES III) reference, suggesting this is an important developmental strategy in lean populations.

CONCLUSION

Documenting growth patterns under diverse preindustrial energetic conditions provides an important baseline for understanding sex differences in body fat emerging today under food abundance.

The effect of reproductive state on activity budget, feeding behavior, and urinary C-peptide levels in wild female Assamese macaques

Abstract

The source of maternal energy supporting reproduction (i.e., stored or incoming) is an important factor determining different breeding strategies (capital, income or mixed) in female mammals. Key periods of energy storage and allocation might induce behavioral and physiological shifts in females, and investigating their distribution throughout reproduction helps in determining vulnerable phases shaping female reproductive success. Here, we examined the effects of reproductive state on activity budget, feeding behavior, and urinary C-peptide (uCP) levels, a physiological marker of energy balance, in 43 wild female Assamese macaques (Macaca assamensis). Over a 13-month study period, we collected 96,266 instantaneous records of activity and 905 urine samples. We found that early lactating females and non-gestating–non-lactating females follow an energy-saving strategy consisting of resting more at the expense of feeding and consuming mostly fruits which contributed to enhancing their energy intake and feeding efficiency. We found an opposite pattern in gestating and late lactating females who feed more at the expense of resting and consume mostly seeds, providing a fiber-rich diet. Storing food into cheek pouches increased throughout gestation while it decreased all along with lactation. Lastly, we found the highest uCP levels during late gestation. Our results reflect different feeding adaptations in response to the energetic costs of reproduction and suggest a critical role of fat accumulation before conception and metabolizing fat during gestation and lactation. Overall, our study provides an integrative picture of the energetics of reproduction in a seasonal species and contributes to our understanding of the diversity of behavioral and physiological adaptations shaping female reproductive success.

Significance statement

To offset their substantial energetic investment in reproduction, mammalian females may modify their behavior and the way they extract energy from their environment. In addition, as a result of heightened energy expenditure, female reproduction might trigger physiological shifts. To date, most studies investigated the energetic costs of female reproduction using either a behavioral or a physiological approach. To arrive at a more comprehensive picture, we combined behavioral data with a physiological marker of energy balance, i.e., urinary C-peptide, in a seasonal primate species in its natural habitat. Our results indicate that throughout the reproductive cycle, behavioral and physiological adaptations operate concomitantly, inducing modifications in female activity budget, feeding behavior, and suggesting shifts in fat use. Overall, our results illustrate the relevance of combining data on behavior and hormones to investigate breeding strategies in coping with the energetic costs of reproduction.

The evolution of perennially enlarged breasts in women: a critical review and a novel hypothesis

The possession of permanent, adipose breasts in women is a uniquely human trait that develops during puberty, well in advance of the first pregnancy. The adaptive role and developmental pattern of this breast morphology, unusual among primates, remains an unresolved conundrum. The evolutionary origins of this trait have been the focus of many hypotheses, which variously suggest that breasts are a product of sexual selection or of natural selection due to their putative role in assisting in nursing or as a thermoregulatory organ. Alternative hypotheses assume that permanent breasts are a by-product of other evolutionary changes. We review and evaluate these hypotheses in the light of recent literature on breast morphology, physiology, phylogeny, ontogeny, sex differences, and genetics in order to highlight their strengths and flaws and to propose a coherent perspective and a new hypothesis on the evolutionary origins of perennially enlarged breasts in women. We propose that breasts appeared as early as Homo ergaster, originally as a by-product of other coincident evolutionary processes of adaptive significance. These included an increase in subcutaneous fat tissue (SFT) in response to the demands of thermoregulatory and energy storage, and of the ontogenetic development of the evolving brain. An increase in SFT triggered an increase in oestradiol levels (E2). An increase in meat in the diet of early Homo allowed for further hormonal changes, such as greater dehydroepiandrosterone (DHEA/S) synthesis, which were crucial for brain evolution. DHEA/S is also easily converted to E2 in E2-sensitive body parts, such as breasts and gluteofemoral regions, causing fat accumulation in these regions, enabling the evolution of perennially enlarged breasts. Furthermore, it is also plausible that after enlarged breasts appeared, they were co-opted for other functions, such as attracting mates and indicating biological condition. Finally, we argue that the multifold adaptive benefits of SFT increase and hormonal changes outweighed the possible costs of perennially enlarged breasts, enabling their further development.

Does Nubility Indicate More Than High Reproductive Value? Nubile Primiparas' Pregnancy Outcomes in Evolutionary Perspective

The idea that human males are most strongly attracted to traits that peak in women in the nubile age group raises the question of how well women in that age group contend with the potential hazards of a first pregnancy. Using data for 1.7 million first births from 1990 U.S. natality and mortality records, we compared outcomes for women with first births (primiparas) aged 16-20 years (when first births typically occur in forager and subsistence groups) with those aged 21-25 years. The younger primiparas had a much lower risk of potentially life-threatening complications of labor and delivery and, when evolutionarily novel risk factors were controlled, fetuses which were significantly more likely to survive despite lower birth weights. Thus, nubile primiparas were more likely to have a successful reproductive outcome defined in an evolutionarily relevant way (an infant of normal birth weight and gestation, surviving to one year, and delivered without a medically necessary cesarean delivery). This suggests that prior to the widespread availability of surgical deliveries, men who mated with women in the nubile age group would have reaped the benefit of having a reproductive partner more likely to have a successful first pregnancy.

The role of epidemiology studies in human health risk assessment of polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) are a public health concern given evidence that they persist and accumulate in the environment and can cause toxic effects in animals and humans. However, evaluating adverse effects of PCBs in epidemiologic studies is complicated by the characteristics of PCB exposure. PCBs exist as mixtures in the environment; the mixture changes over time due to degradation, and given physicochemical differences between specific PCB congeners, the mixture that an individual is exposed to (via food, air, or other sources) is likely different from that which can be measured in biological tissues. This is particularly problematic when evaluating toxicity of shorter-lived congeners that may not be measurable by the time biological samples are collected. We review these and other issues that arise when evaluating epidemiologic studies of PCBs and discuss how epidemiology data can still be used to inform both hazard identification and dose-response evaluation.

Body composition helps: Differences in energy expenditure between pregnant and nonpregnant females

OBJECTIVES

Human pregnancy is associated with important physiological changes that usually increase energetic requirements. However, great variability exists in the costs and mechanisms required to bear pregnancy. Since body mass (BM) and composition are modified during gestation, it is of great interest to compare the influence of BM on energy expenditure (EE) in pregnant and nonpregnant females.

METHODS

BM, body composition, and EE of 77 volunteers (35 pregnant and 42 nonpregnant females) were measured. The pregnant volunteers completed two measurement rounds at 28 and 32 gestation weeks. Differences on the measured parameters were sought, and comparison of regression lines was computed to test how BM affected the EE of the volunteers.

RESULTS

BM and body composition parameters are significantly higher in pregnant females, but EE is not statistically different. Pregnant females have a larger percentage of fat mass, but lower percentage of fat-free mass (FFM). The EE per kg of FFM is similar in both groups. Comparison of regression lines shows that pregnancy does not change the relationship between BM and EE, but for similar BM pregnant females expend less energy than nonpregnant females.

CONCLUSIONS

We propose that their larger percentage of passive body tissues is the reason why pregnant females expend less energy than nonpregnant females of similar BM, without changing the scaling of EE on BM. Thus, pregnancy could not be as energetically constraining as usually assumed, with important consequences for human reproductive ecology.

Adipose Tissue Development and Expansion from the Womb to Adolescence: An Overview

Prevalence rates of pediatric obesity continue to rise worldwide. Adipose tissue (AT) development and expansion initiate in the fetus and extend throughout the lifespan. This paper presents an overview of the AT developmental trajectories from the intrauterine period to adolescence; factors determining adiposity expansion are also discussed. The greatest fetal increases in AT were observed in the third pregnancy trimester, with growing evidence suggesting that maternal health and nutrition, toxin exposure, and genetic defects impact AT development. From birth up to six months, healthy term newborns experience steep increases in AT; but a subsequent reduction in AT is observed during infancy. Important determinants of AT in infancy identified in this review included feeding practices and factors shaping the gut microbiome. Low AT accrual rates are maintained up to puberty onset, at which time, the pattern of adiposity expansion becomes sex dependent. As girls experience rapid increases and boys experience decreases in AT, sexual dimorphism in hormone secretion can be considered the main contributor for changes. Eating patterns/behaviors and interactions between dietary components, gut microbiome, and immune cells also influence AT expansion. Despite the plasticity of this tissue, substantial evidence supports that adiposity at birth and infancy highly influences its levels across subsequent life stages. Thus, a unique window of opportunity for the prevention and/or slowing down of the predisposition toward obesity, exists from pregnancy through childhood.

Frailty: A cost incurred by reproduction?

Evolutionary theories of senescence, such as the ‘disposable soma’ theory, propose that natural selection trades late survival for early fecundity. ‘Frailty’, a multidimensional measure of health status, may help to better define the long-term consequences of reproduction. We examined the relationship between parity and later life frailty (as measured by the Frailty Index) in a sample of 3,534 adults aged 65 years and older who participated in the English Longitudinal Study of Ageing. We found that the most parous adults were the most frail and that the parity-frailty relationship was similar for both sexes. Whilst this study provided some evidence for a ‘parity-frailty trade-off’, there was little support for our hypothesis that the physiological costs of childbearing influence later life frailty. Rather, behavioural and social factors associated with rearing many children may have contributed to the development of frailty in both sexes.

Thigh Adipocyte Size is Inversely Related to Energy Intake and Respiratory Quotient in Healthy Women

OBJECTIVE

The relationship between adipocyte size and ad libitum energy intake has not been previously examined. This study hypothesized an inverse relationship between adipocyte size and daily energy intake (DEI).

METHODS

Seventy healthy adults (39 men and 31 women; BMI 30.0  [SD 6.3]) underwent dual-energy x-ray absorptiometry and subcutaneous fat biopsies from the abdomen and thigh. Osmium-fixed adipocytes were sized with a Coulter counter. Volunteers self-selected food from a vending machine paradigm as the only source of energy intake over 3 days as inpatients. Volunteers also had 24-hour respiratory quotient (RQ) measured in a whole-room indirect calorimeter.

RESULTS

In women, the large cell peak diameter of the thigh depot was greater than that of the abdominal depot (Δ = +15.8 μm; P < 0.0001). In women, thigh peak diameter was inversely associated with DEI (β = -264.7 kcal/d per 10-μm difference; P = 0.03) after adjusting for demographics and body composition. The thigh peak diameter in women was associated with 24-hour RQ (r = -0.47, P = 0.04) after adjusting for demographics, body composition, and 24-hour energy balance. These associations did not extend to men or the abdominal depot.

CONCLUSIONS

In women, thigh adipocyte size was associated with reduced DEI and 24-hour RQ, indicating a special role for thigh fat in women. This depot-specific sexual dimorphism indicates common regulation of energy intake and adipocyte size in the thigh region of women.

Life History Transitions at the Origins of Agriculture: A Model for Understanding How Niche Construction Impacts Human Growth, Demography and Health

Over recent millennia, human populations have regularly reconstructed their subsistence niches, changing both how they obtain food and the conditions in which they live. For example, over the last 12,000 years the vast majority of human populations shifted from foraging to practicing different forms of agriculture. The shift to farming is widely understood to have impacted several aspects of human demography and biology, including mortality risk, population growth, adult body size, and physical markers of health. However, these trends have not been integrated within an over-arching conceptual framework, and there is poor understanding of why populations tended to increase in population size during periods when markers of health deteriorated. Here, we offer a novel conceptual approach based on evolutionary life history theory. This theory assumes that energy availability is finite and must be allocated in competition between the functions of maintenance, growth, reproduction, and defence. In any given environment, and at any given stage during the life-course, natural selection favours energy allocation strategies that maximise fitness. We argue that the origins of agriculture involved profound transformations in human life history strategies, impacting both the availability of energy and the way that it was allocated between life history functions in the body. Although overall energy supply increased, the diet composition changed, while sedentary populations were challenged by new infectious burdens. We propose that this composite new ecological niche favoured increased energy allocation to defence (immune function) and reproduction, thus reducing the allocation to growth and maintenance. We review evidence in support of this hypothesis and highlight how further work could address both heterogeneity and specific aspects of the origins of agriculture in more detail. Our approach can be applied to many other transformations of the human subsistence niche, and can shed new light on the way that health, height, life expectancy, and fertility patterns are changing in association with globalization and nutrition transition.

Prevalence of abdominal obesity and its correlates among adults in a peri-urban population of West Africa

Introduction

Prevalence of abdominal obesity dramatically increases both in developed countries and in developing countries. In several regions in Africa, obesity (especially abdominal) is seen as a sign of affluence, dignity and respect. The objective of this study was to determine prevalence of abdominal obesity and seek some factors associated in a peri-urban population of West Africa.

Methods

During April-May 2014, a cross-sectional study was conducted in Anonkoi 3, a neighborhood of Abidjan (Ivory Coast). Adults of 18 years old and over, not bedridden were included. Sampling was done in two stages. First, we selected the households. Then in each household we randomly chose one adult. Abdominal obesity was measured using a measuring tape and defined by waist circumference ratio (TT) to hip circumference (TH) greater or equal to 0.80 in women and greater or equal to 0.95 in men. Data from sociodemographic, corpulence, socioeconomic level, food habit, level of physical activity and blood pressure were analyzed. Univariate analysis using the Pearson KHI-square test at a significance level of 0.05 and a logistic regression was performed.

Results

We visited 486 households in which 486 people aged 36.1 ± 12.83 years agreed to participate in the study. Prevalence of abdominal obesity was 50.8%. Those aged 30–45 years, women, couples, those with a primary level of education, the poor, people with high blood pressure, subjects less active and obese (general obesity) had more abdominal obesity. After logistic regression, individuals aged 30–45 years (adjusted OR = 2.35; p = 0.004) and 45 years and older (adjusted OR = 3.18; p = 0.001); females (adjusted OR = 49.05; p = 0.000); hypertension (adjusted OR = 2.26; p = 0.014) and obesity (OR = 2.94; p = 0.009).

Conclusion

This work allowed us to estimate a relatively high prevalence of abdominal obesity in a peri-urban African population.

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.

Lactation and maternal cardiovascular disease risk in later life

Cardiovascular disease is the leading cause of death worldwide. The identification of protective factors against cardiovascular disease is important with regard to public health policies. Lactation has multiple beneficial effects for both mother and child. This review summarizes the evidence on the association between lactation and maternal cardiovascular risk in later life. Lactation may help to reverse the metabolic and cardiovascular changes that take place during pregnancy. Overall, lactation seems to exert a protective effect against the development of hypertension, metabolic syndrome, and diabetes, whilst data on postpartum weight and lipidemic profile are less conclusive. Both subclinical and clinical cardiovascular disease are negatively associated with a history of lactation. Increased energy expenditure and a favorable hormonal and adipokine profile during lactation may explain these associations.

Adiposity markers and its association with age at menarche: A comparative study among rural and urban Meitei females of Manipur, North-East India

BACKGROUND

Menarche is a critical biomarker in the reproductive life of females. Early age at menarche may represent an indicator of adult adiposity. The study examines the association of various adiposity markers with age at menarche in rural and urban Meitei females of Manipur, India.

METHODS

A cross-sectional study was conducted among rural and urban Meitei females of Manipur of age 18-45 years. Detailed information of the participants was taken with the help of proforma. Various anthropometric and physiological measurements were also recorded.

RESULTS

Mean age at menarche was 12.5 years for urban females and 13.1 years for rural females. Females of urban and rural areas under overweight category of BMI had higher odds of attaining early menarche. Odds of having early menarche were found to be highest among those with risk category of waist hip ratio, waist height ratio and waist circumference in both rural and urban females.

CONCLUSION

Females with higher body mass index, high waist-to-hip ratio and waist height ratio were found to be at risk of early menarche.

Decreased beta-cell function in breastfeeding obese and non-obese women: A prospective observational study

BACKGROUND & AIMS

Obesity is associated with lower breastfeeding rates. The underlying pathophysiological mechanisms are not well-understood, but there is increasing evidence on an association between parameters of maternal glucose metabolism and prolactin concentrations. In this cross-sectional observational study we investigate the relationship between breastfeeding, maternal obesity, and maternal glucose metabolism postpartum with beta cell function as a primary outcome measure.

METHODS

We investigated 106 women (44% obese) prospectively recruited during the pregnancy, who underwent a 75 g - 2 h oral glucose tolerance test (OGTT) between the 3rd and 5th months postpartum. At this time point, we tested the relationship between breastfeeding status, maternal prolactin concentrations, maternal obesity, and fasting and dynamic indices of glucose metabolism using multivariate logistic regression in a post hoc analysis of prospective observational data.

RESULTS

During the study visit at a mean of 122 (SE 9.3) days after delivery, 47% of obese women and 68% of non-obese women were breastfeeding (p < 0.05). Lactation and higher prolactin concentrations were associated with lower prepregnancy weight and lower postpartum insulin concentrations. Prehepatic beta-cell function was decreased in both obese (mean (SD); 0.16 (0.04) vs. 0.19 (0.05), p < 0.05) and non-obese (0.12 (0.05) vs. 0.16 (0.06), p < 0.01), lactating women. Obese lactating women have significantly lower first (1135.1 (306.7) pmol/L vs. 1517.3 (475.8) pmol/L, p < 0.01) and second phase insulin secretion (mean (SD), 300.2 (70.7) pmol/L vs. 393.1 (115.5) pmol/L, p < 0.01) as shown by Stumvoll indices when comparing to obese non-lactating women. Prehepatic beta-cell function and Stumvoll 1st phase insulin secretion index, but not BMI, were independently and negatively associated with breastfeeding and circulating prolactin concentrations.

CONCLUSIONS

Beta-cell function during lactation relates to breastfeeding and circulating prolactin concentrations independently of obesity. The well-known positive effects of lactation on maternal and offspring outcomes might reflect a causative relationship of higher breastfeeding rates in metabolically healthier women.

Prevalence and correlates of abdominal obesity among adults in Uganda: findings from a national cross-sectional, population based survey 2014

Background

Overweight and obesity are associated with health complications the gravity of which, vary with the regional deposition of the excess fat. The Body Mass Index (BMI) is often used to measure obesity although is an inferior predictor of cardiovascular disease risk mortality and morbidity compared with measures of abdominal obesity. We analyzed data from Uganda’s 2014 World Health Organization (WHO) STEPwise approach to surveillance of Non-communicable diseases (NCDs) survey to estimate the prevalence of abdominal obesity and associated factors to provide information on the prevention and control of overweight and obesity.

Methods

Data were collected using the WHO STEPS protocol. Waist measurement was taken using a non-stretchable standard tape measure mid-way between the lowest rib and iliac crest with the subject standing at the end of gentle expiration. Participants with waist circumference > 102 cm for men and 88 cm for women were classified as abdominally obese. We used weighted modified Poisson regression with robust error variance to estimate the prevalence of abdominal obesity and associated factors.

Results

Of the 3676 participants, 432 (11.8%) were abdominally obese; with the prevalence higher among females 412 (19.5%) compared with males 20 (1.3%). Compared with males, female participants were more likely to be abdominally obese Adjusted Prevalence Rate Ratio (APRR) 7.59 [5.58–10.33]. Participants who were married or cohabiting APRR 1.82 [1.29–2.57] and participants who were separated or divorced APRR 1.69 [1.17–2.46] were more likely to be abdominally obese compared with those who had never married before. Compared with rural dwellers, participants from urban areas were more likely to be abdominally obese APRR 1.29 [1.09–1.53]. Compared with participants with normal blood pressure, those with elevated blood pressure were more likely to be abdominally obese APRR 1.83 [1.57–2.14].Compared with participants without any education, those with secondary education were more likely to be abdominally obese APRR 1.42 [1.12–1.78].

Conclusions

There is a high prevalence of abdominal obesity among adults in Uganda which puts many at risk of developing associated metabolic complications. These data provide useful information for developing interventions and formulation of policies for the control and prevention of abdominal obesity in Uganda.

Mammary cell proliferation and catabolism of adipose tissues in nutrition-restricted lactating sows were associated with extracellular high glutamate levels

Background

Persistent lactation, as the result of mammary cellular anabolism and secreting function, is dependent on substantial mobilization or catabolism of body reserves under nutritional deficiency. However, little is known about the biochemical mechanisms for nutrition-restricted lactating animals to simultaneously maintain the anabolism of mammary cells while catabolism of body reserves. In present study, lactating sows with restricted feed allowance (RFA) (n = 6), 24% feed restriction compared with the control (CON) group (n = 6), were used as the nutrition-restricted model. Microdialysis and mammary venous cannulas methods were used to monitor postprandial dynamic changes of metabolites in adipose and mammary tissues.

Results

At lactation d 28, the RFA group showed higher (P < 0.05) loss of body weight and backfat than the CON group. Compared with the CON group, the adipose tissue of the RFA group had higher (P < 0.05) extracellular glutamate and insulin levels, increased (P < 0.05) lipolysis related genes (HSL and ATGL) expression, and decreased (P < 0.05) glucose transport and metabolism related genes (VAMP8, PKLR and LDHB) expression. These results indicated that under nutritional restriction, reduced insulin-mediated glucose uptake and metabolism and increased lipolysis in adipose tissues was related to extracellular high glutamate concentration. As for mammary glands, compared with the CON group, the RFA group had up-regulated (P < 0.05) expression of Notch signaling ligand (DLL3) and receptors (NOTCH2 and NOTCH4), higher (P < 0.05) extracellular glutamate concentration, while expression of cell proliferation related genes and concentrations of most metabolites in mammary veins were not different (P > 0.05) between groups. Accordingly, piglet performance and milk yield did not differ (P > 0.05) between groups. It would appear that activation of Notch signaling and adequate supply of glutamate might assist mammogenesis.

Conclusions

Mammary cell proliferation and catabolism of adipose tissues in nutrition-restricted lactating sows were associated with extracellular high glutamate levels.

Electronic supplementary material

The online version of this article (10.1186/s40104-018-0293-6) contains supplementary material, which is available to authorized users.

Young adult pregnancy status and the risk of developing overweight and obesity among women and men

Pregnancies can end in miscarriage, birth or termination. Although it is well known that pregnancy results in weight gain across the life course, it is unknown whether pregnancies which end in termination and miscarriage contribute to this. The study used a sub-sample of 3630 adult offspring from the original cohort of the Mater University of Queensland Study of Pregnancy (MUSP) and its outcomes, in Brisbane, Australia. Anthropometric data were measured at 5, 14 and 21 years of age and experience of pregnancy including termination, miscarriage and births were self-reported at 21 years. Multivariable analyses were conducted to determine whether pregnancy status of young people independently associated with overweight or obesity status. The women who had at least one birth were more likely to have overweight (odds ratio [OR] 1.52; 95% confidence interval [CI]: 1.01, 2.27) or obese (OR 2.38; 95% CI: 1.58, 3.59) compared to women who did not experience any pregnancy. Women whose pregnancies were terminated or miscarried were at the same risk of overweight or obesity as women who did not experience any pregnancy. For men, there is no association between the pregnancies in their partners and the mean difference in their body mass index. Young women whose pregnancies result in a birth, but not terminations or miscarriages, are at greater risk of having overweight or obesity following the birth.

Do the Low WHRs and BMIs Judged Most Attractive Indicate Higher Fertility?

We examine the widely accepted view that very low waist-hip ratios and low body mass indices (BMIs) in women in well-nourished populations are judged attractive by men because these features reliably indicate superior fertility. In both subsistence and well-nourished populations, relevant studies of fertility do not support this view. Rather studies indicate lower fertility in women with anthropometric values associated with high attractiveness. Moreover, low maternal BMI predisposes to conditions that compromise infant survival. Consistent with these findings from the literature, new data from a large U.S. sample of women past reproductive age show that women with lower BMIs in the late teens had fewer live births, controlling for education, marital history, and race. They also had later menarche and earlier menopause compared with women with higher youth BMIs. In addition, data from the 2013 U.S. natality database show that mothers with lower prepregnancy BMIs have an increased risk of producing both low-birth-weight and preterm infants controlling for other relevant variables-conditions that would have adversely affected fitness over almost all of human evolution. Thus, a review of the relevant literature and three new tests fail to support the view that highly attractive women are more fertile.

Do the Low WHRs and BMIs Judged Most Attractive Indicate Better Health?

It is widely claimed that in well-nourished populations, very low female waist-hip ratios (WHRs) together with low body mass indices (BMIs) are judged attractive by men because these features reliably indicate superior health and fertility. However, studies show that mortality rates are higher in women with low BMIs than in women with average BMIs and are inversely related to BMI in subsistence populations. Measures of current health in women of reproductive age have not been similarly studied. We analyze large U.S. samples of reproductive-age women and show that controlling for other factors known to affect health, those with low BMIs (<20), WHRs, or waist/stature ratios did not have better health than those with values in the middle range, and there was no relationship between subsequent health outcomes and BMI in early adulthood. Lower self-reported BMIs were linked to poorer health and an increased risk of infection. However, based on recent U.S. natality data, primiparas with lower BMIs had a lower risk of an operative delivery and of gestational hypertension. Beyond these two parity-restricted effects, relevant studies and new tests fail to support the view that women with the very low BMIs and WHRs consistently judged attractive are generally healthier than women with average values; significant correlations were consistently in the opposite direction.

Irisin Maternal Plasma and Cord Blood Levels in Mothers with Spontaneous Preterm and Term Delivery

Irisin, an adipomyokine identified in 2012, has been investigated in association with common pregnancy complications, including gestational diabetes mellitus, preeclampsia, and intrauterine growth restriction. The objective of this study is to examine the potential role of irisin in preterm birth (PTB) by comparing its level between mothers with term and preterm labor. Maternal peripheral blood and cord blood samples were collected from 30 mothers who delivered prematurely and from 35 mothers who delivered at term. Irisin concentrations were measured in all samples using ELISA, and four common single nucleotide polymorphisms in the irisin gene were determined (rs16835198, rs726344, rs3480, and rs1746661). Univariable and multivariable regression modeling was applied to evaluate maternal and cord blood irisin concentrations in relation to preterm/term labor. Irisin concentration in umbilical cord blood was found to be associated with PTB in the univariable model (p = 0.046). On the other hand, no differences in maternal blood irisin levels between mothers with preterm and term deliveries were established. To the best of our knowledge, this is the first study determining irisin levels in term and preterm deliveries in maternal peripheral blood and umbilical cord blood. Our study shows a possible association between cord blood irisin concentration and PTB occurrence.

Cumulative Lactation and Onset of Hypertension in African-American Women

Hypertension affects nearly 1 of 3 women and contributes to cardiovascular disease, the leading cause of death in the United States. Breastfeeding leads to metabolic changes that could reduce risks of hypertension. Hypertension disproportionately affects black women, but rates of breastfeeding among black women lag behind those in the general population. In the Black Women's Health Study (n = 59,001), we conducted a nested case-control analysis using unconditional logistic regression to estimate the association between breastfeeding and incident hypertension at ages 40-65 years using data collected from 1995 to 2011. Controls were frequency-matched 2:1 to 12,513 hypertensive women by age and questionnaire cycle. Overall, there was little evidence of association between ever breastfeeding and incident hypertension (odds ratio = 0.97, 95% confidence interval: 0.92, 1.02). However, age modified the relationship (P = 0.02): Breastfeeding was associated with reduced risk of hypertension at ages 40-49 years (odds ratio = 0.92, 95% confidence interval: 0.85, 0.99) but not at older ages. In addition, risk of hypertension at ages 40-49 years decreased with increasing duration of breastfeeding (P for trend = 0.08). Our results suggest that long-duration breastfeeding may reduce the risk of incident hypertension in middle age. Addressing breastfeeding as a potential preventative health behavior is particularly compelling because it is required for only a discrete period of time.

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.

Correlation between Body Mass Index and abdominal circumference in Belgian adults: a cross-sectional study

INTRODUCTION

Traditionally, the body mass index (BMI) is used to describe anthropometric measurements and to assess weight-related health risks. However, the abdominal circumference (AC) might also be a valuable parameter to estimate this risk. This study aims to describe an association between the BMI and the AC.

MATERIAL AND METHODS

Participants were recruited during the Brussels Food Fair in 2014. They completed a questionnaire with their medical history, and health related parameters such as blood pressure, weight, height and AC were measured.

RESULTS

In total, 705 participants were analyzed. Men had a mean BMI of 27.3 kg/m2 and a mean AC of 98.7 cm. Women had a mean BMI of 26.0 kg/m2 and a mean AC of 88.2 cm. The Pearson's correlation coefficient between the BMI and the AC was 0.91 for men and 0.88 for women. There was a strong positive correlation between the BMI and the AC. In the identification of patients at high risk for weight-related diseases, the use of the AC identified more patients than the BMI. Especially more women were ranking in a higher risk class with the AC than with the BMI classification. Both the BMI as well as the AC identified most diseases with an increased relative risk.

CONCLUSION

There is a strong correlation between the BMI and the AC. There are too few arguments to prefer the use of AC above the BMI to detect people at high risk for weight-related diseases.

Sexual dimorphisms in genetic loci linked to body fat distribution

Obesity is a chronic condition associated with increased morbidity and mortality and is a risk factor for a number of other diseases including type 2 diabetes and cardiovascular disease. Obesity confers an enormous, costly burden on both individuals and public health more broadly. Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes. Body fat distribution is distinct from overall obesity in measurement, but studies of body fat distribution can yield insights into the risk factors for and causes of overall obesity. Sexual dimorphism in body fat distribution is present throughout life. Though sexual dimorphism is subtle in early stages of life, it is attenuated in puberty and during menopause. This phenomenon could be, at least in part, due to the influence of sex hormones on the trait. Findings from recent large genome-wide association studies (GWAS) for various measures of body fat distribution (including waist-to-hip ratio, hip or waist circumference, trunk fat percentage and the ratio of android and gynoid fat percentage) emphasize the strong sexual dimorphism in the genetic regulation of fat distribution traits. Importantly, sexual dimorphism is not observed for overall obesity (as assessed by body mass index or total fat percentage). Notably, the genetic loci associated with body fat distribution, which show sexual dimorphism, are located near genes that are expressed in adipose tissues and/or adipose cells. Considering the epidemiological and genetic evidence, sexual dimorphism is a prominent feature of body fat distribution. Research that specifically focuses on sexual dimorphism in fat distribution can provide novel insights into human physiology and into the development of obesity and its comorbidities, as well as yield biological clues that will aid in the improvement of disease prevention and treatment.

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.

What Makes Jessica Rabbit Sexy? Contrasting Roles of Waist and Hip Size

While waist/hip ratio (WHR) and body mass index (BMI) have been the most studied putative determinants of female bodily attractiveness, BMI is not directly observable, and few studies have considered the independent roles of waist and hip size. The range of attractiveness in many studies is also quite limited, with none of the stimuli rated as highly attractive. To explore the relationships of these anthropometric parameters with attractiveness across a much broader spectrum of attractiveness, we employ three quite different samples: a large sample of college women, a larger sample of Playboy Playmates of the Month than that has been previously examined, and a large pool of imaginary women (e.g., cartoon, video game, graphic novel characters) chosen as the “most attractive” by university students. Within-sample and between-sample comparisons agree in indicating that waist size is the key determinant of female bodily attractiveness and accounts for the relationship of both BMI and WHR with attractiveness, with between-sample effect sizes of 2.4–3.2. In contrast, hip size is much more similar across attractiveness groups and is unrelated to attractiveness when BMI or waist size is controlled.

Lactation and appetite-regulating hormones: increased maternal plasma peptide YY concentrations 3-6 months postpartum

Breast-feeding is associated with maternal hormonal and metabolic changes ensuring adequate milk production. In this study, we investigate the impact of breast-feeding on the profile of changes in maternal appetite-regulating hormones 3-6 months postpartum. Study participants were age- and BMI-matched lactating mothers (n 10), non-lactating mothers (n 9) and women without any history of pregnancy or breast-feeding in the previous 12 months (control group, n 10). During study sessions, young mothers breast-fed or bottle-fed their babies, and maternal blood samples were collected at five time points during 90 min: before, during and after feeding the babies. Outcome parameters were plasma concentrations of ghrelin, peptide YY (PYY), leptin, adiponectin, prolactin, cortisol, insulin, glucose and lipid values. At baseline, circulating PYY concentrations were significantly increased in lactating mothers (100·3 (se 6·7) pg/ml) v. non-lactating mothers (73·6 (se 4·9) pg/ml, P=0·008) and v. the control group (70·2 (se 9) pg/ml, P=0·021). We found no differences in ghrelin, leptin and adiponectin values. Baseline prolactin concentrations were over 4-fold higher in lactating mothers (P<0·001). Lactating women had reduced TAG levels and LDL-cholesterol:HDL-cholesterol ratio, but increased waist circumference, when compared with non-lactating women. Breast-feeding sessions further elevated circulating prolactin (P<0·001), but induced no acute effects on appetite-regulating hormones. In summary, one single breast-feeding session did not acutely modulate circulating appetite-regulating hormones, but increased baseline PYY concentrations are associated with prolonged lactation. PYY might play a role in the coordination of energy balance during lactation, increasing fat mobilisation from maternal depots and ensuring adequate milk production for the demands of the growing infant.

Ethnic differences in BMI, subcutaneous fat, and serum leptin levels during and after pregnancy and risk of gestational diabetes

OBJECTIVE

To explore the differences between Europeans and South Asians in BMI, subcutaneous fat, and serum leptin (s-leptin) levels during and after pregnancy and their relationship with gestational diabetes (GDM).

DESIGN

Multi-ethnic population-based cohort study, whereof 353 Europeans (93.1% of the included) and 190 South Asians (95.0% of the included).

METHODS

S-leptin, BMI, and subcutaneous fat (sum of triceps, subscapular, and suprailiac skinfolds) were measured at 14 and 28 weeks of gestation, and 14 weeks after delivery. GDM was diagnosed with the WHO criteria 2013.

RESULTS

South Asians had similar thickness of the triceps and suprailiac skinfolds, thicker subscapular skinfold, and higher s-leptin than Europeans in early pregnancy, despite lower BMI. South Asians retained more subcutaneous fat (mean (95% CI) 10.0 (7.4-12.7) mm vs 3.8 (1.9-5.8) mm) and BMI (1.5 (1.2-1.8) kg/m(2) vs 0.1 (-0.1 to 0.3) kg/m(2)) than Europeans 14 weeks after delivery and s-leptin decreased less in South Asians than Europeans (-0.13 (-0.27 to -0.00) μg/l vs -0.47 (-0.57 to -0.37) μg/l, P<0.001 for all). The prevalence of GDM was 23.8% (n=84) in Europeans and 42.6% (n=81) in South Asians. BMI, subcutaneous fat, and s-leptin were all positively associated with GDM, also after adjustment for covariates.

CONCLUSIONS

The relatively high amounts of subcutaneous fat and s-leptin in South Asians in early pregnancy contributed to their increased risk of GDM. South Asians retained more weight and subcutaneous fat after delivery, potentially increasing their risk of adiposity and GDM in future pregnancies.

The Relationship between Retinol-Binding Protein 4 Concentrations and Gestational Diabetes Mellitus in Chinese Women

BACKGROUND

This study aimed to investigate the relationship between retinol-binding protein 4 (RBP4) and gestational diabetes mellitus (GDM).

METHODS

Seventy-six women with and without GDM were recruited. Their blood samples were collected to detect RBP4, fasting plasma glucose (FPG), fasting insulin (Fins), triglyceride (TG), total cholesterol (TC), low-density lipoprotein, high-density lipoprotein (HDL) and glycosylated hemoglobin (HbA1c) levels.

RESULTS

RBP4 (21.42 ± 3.846 vs. 39.08 ± 8.293 μg/ml), FPG, Fins, homeostasis model assessment of insulin resistance (HOMA-IR), HbA1c, and TG levels were higher, while HDL levels were lower in women with GDM (p < 0.01). In healthy controls, RBP4 concentrations were positively correlated with HOMA-IR and TG and inversely correlated with FPG and HDL (p < 0.05). Serum concentrations of RBP4 in women with GDM were inversely correlated with TC and positively correlated with maternal weight gain during pregnancy (p < 0.05). The ROC curve was drawn with a correct rate of 93.4%.

CONCLUSIONS

Concentrations of serum RBP4 were significantly higher in women with GDM, suggesting that elevated RPB4 level may play a role in the pathogenesis of GDM. Meanwhile, RBP4 might be a good predictor of GDM. RBP4 is correlated with TG and HDL, indicating that RBP4 plays a role in alterations of lipid metabolism in pregnant women. © 2015 S. Karger AG, Basel.