A Stress Reduction Intervention for Lactating Mothers Alters Maternal Gut, Breast Milk, and Infant Gut Microbiomes: Data from a Randomized Controlled Trial.

BACKGROUND: This secondary analysis of data from a randomized controlled trial (RCT) investigated how the maternal gut, breast milk, and infant gut microbiomes may contribute to the effects of a relaxation intervention, which reduced maternal stress and promoted infant weight gain. METHODS: An RCT was undertaken in healthy Chinese primiparous mother-infant pairs (340/7-376/7gestation weeks). Mothers were randomly allocated to either the intervention group (IG, listening to relaxation meditation) or the control group (CG). Outcomes were the differences in microbiome composition and the diversity in the maternal gut, breast milk, and infant gut at 1 (baseline) and 8 weeks (post-intervention) between IG and CG, assessed using 16S rRNA gene amplicon sequencing of fecal and breastmilk samples. RESULTS: In total, 38 mother-infant pairs were included in this analysis (IG = 19, CG = 19). The overall microbiome community structure in the maternal gut was significantly different between the IG and CG at 1 week, with the difference being more significant at 8 weeks (Bray-Curtis distance R2 = 0.04 vs. R2 = 0.13). Post-intervention, a significantly lower α-diversity was observed in IG breast milk (observed features: CG = 295 vs. IG = 255, p = 0.032); the Bifidobacterium genera presented a higher relative abundance. A significantly higher α-diversity was observed in IG infant gut (observed features: CG = 73 vs. IG = 113, p < 0.001). CONCLUSIONS: The findings were consistent with the hypothesis that the microbiome might mediate observed relaxation intervention effects via gut-brain axis and entero-mammary pathways; but confirmation is required.

Plant-Based Diets in Children: Secular Trends, Health Outcomes, and a Roadmap for Urgent Practice Recommendations and Research-A Systematic Review.

People are increasingly encouraged to reduce animal food consumption and shift towards plant-based diets; however, the implications for children's health are unclear. In this narrative review of research in high-income settings, we summarize evidence on the increasing consumption of plant-based diets in children and update an earlier systematic review regarding their associations with children's health outcomes. The evidence indicates that vegan, but not vegetarian, diets can restrict growth relative to omnivorous children and increase the risk of being stunted and underweight, although the percentage affected is relatively small. Bone mineral content is reduced in vegetarian and, in particular, vegan children, compared to omnivores. Both vegetarian and vegan children who do not use vitamin B12 supplements manifest with B12 deficiency; however, supplementation rectifies this problem. Both vegetarians and vegans have lower concentrations of 25(OH)D if unsupplemented, and lower body iron stores, but usually have normal iron metabolism markers. Both groups are at risk of iodine deficiency, and this might affect thyroid health. Children consuming a vegan diet have a more favorable lipid profile than omnivorous children; however, the results for a vegetarian diet are inconsistent and vary by outcome. Based on the same scientific evidence, national and international dietary recommendations are heterogeneous, with some countries supporting plant-based diets among infants, children, and adolescents, and others discouraging them. We offer a research roadmap, highlighting what is needed to provide adequate evidence to harmonize dietary recommendations for plant-based diets in children. A number of measures should urgently be introduced at international and national levels to improve the safety of their use in children.

Reconsidering the developmental origins of adult disease paradigm: The 'metabolic coordination of childbirth' hypothesis.

In uncomplicated pregnancies, birthweight is inversely associated with adult non-communicable disease (NCD) risk. One proposed mechanism is maternal malnutrition during pregnancy. Another explanation is that shared genes link birthweight with NCDs. Both hypotheses are supported, but evolutionary perspectives address only the environmental pathway. We propose that genetic and environmental associations of birthweight with NCD risk reflect coordinated regulatory systems between mother and foetus, that evolved to reduce risks of obstructed labour. First, the foetus must tailor its growth to maternal metabolic signals, as it cannot predict the size of the birth canal from its own genome. Second, we predict that maternal alleles that promote placental nutrient supply have been selected to constrain foetal growth and gestation length when fetally expressed. Conversely, maternal alleles that increase birth canal size have been selected to promote foetal growth and gestation when fetally expressed. Evidence supports these hypotheses. These regulatory mechanisms may have undergone powerful selection as hominin neonates evolved larger size and encephalisation, since every mother is at risk of gestating a baby excessively for her pelvis. Our perspective can explain the inverse association of birthweight with NCD risk across most of the birthweight range: any constraint of birthweight, through plastic or genetic mechanisms, may reduce the capacity for homeostasis and increase NCD susceptibility. However, maternal obesity and diabetes can overwhelm this coordination system, challenging vaginal delivery while increasing offspring NCD risk. We argue that selection on viable vaginal delivery played an over-arching role in shaping the association of birthweight with NCD risk.

Effects of relaxation interventions during pregnancy on maternal mental health, and pregnancy and newborn outcomes: A systematic review and meta-analysis.

BACKGROUND: Stress during pregnancy is detrimental to maternal health, pregnancy and birth outcomes and various preventive relaxation interventions have been developed. This systematic review and meta-analysis aimed to evaluate their effectiveness in terms of maternal mental health, pregnancy and birth outcomes. METHOD: The protocol for this review is published on PROSPERO with registration number CRD42020187443. A systematic search of major databases was conducted. Primary outcomes were maternal mental health problems (stress, anxiety, depression), and pregnancy (gestational age, labour duration, delivery mode) and birth outcomes (birth weight, Apgar score, preterm birth). Randomized controlled trials or quasi-experimental studies were eligible. Meta-analyses using a random-effects model was conducted for outcomes with sufficient data. For other outcomes a narrative review was undertaken. RESULT: We reviewed 32 studies comprising 3,979 pregnant women aged 18 to 40 years. Relaxation interventions included yoga, music, Benson relaxation, progressive muscle relaxation (PMR), deep breathing relaxation (BR), guided imagery, mindfulness and hypnosis. Intervention duration ranged from brief experiment (~10 minutes) to 6 months of daily relaxation. Meta-analyses showed relaxation therapy reduced maternal stress (-4.1 points; 95% Confidence Interval (CI): -7.4, -0.9; 9 trials; 1113 participants), anxiety (-5.04 points; 95% CI: -8.2, -1.9; 10 trials; 1965 participants) and depressive symptoms (-2.3 points; 95% CI: -3.4, -1.3; 7 trials; 733 participants). Relaxation has also increased offspring birth weight (80 g, 95% CI: 1, 157; 8 trials; 1239 participants), explained by PMR (165g, 95% CI: 100, 231; 4 trials; 587 participants) in sub-group analysis. In five trials evaluating maternal physiological responses, relaxation therapy optimized blood pressure, heart rate and respiratory rate. Four trials showed relaxation therapy reduced duration of labour. Apgar score only improved significantly in two of six trials. One of three trials showed a significant increase in birth length, and one of three trials showed a significant increase in gestational age. Two of six trials examining delivery mode showed significantly increased spontaneous vaginal delivery and decreased instrumental delivery or cesarean section following a relaxation intervention. DISCUSSION: We found consistent evidence for beneficial effects of relaxation interventions in reducing maternal stress, improving mental health, and some evidence for improved maternal physiological outcomes. In addition, we found a positive effect of relaxation interventions on birth weight and inconsistent effects on other pregnancy or birth outcomes. High quality adequately powered trials are needed to examine impacts of relaxation interventions on newborns and offspring health outcomes. CONCLUSION: In addition to benefits for mothers, relaxation interventions provided during pregnancy improved birth weight and hold some promise for improving newborn outcomes; therefore, this approach strongly merits further research.

The Associations of Breastfeeding Status at 6 Months with Anthropometry, Body Composition, and Cardiometabolic Markers at 5 Years in the Ethiopian Infant Anthropometry and Body Composition Birth Cohort.

(1) Background: Breastfeeding (BF) has been shown to lower the risk of overweight and cardiometabolic disease later in life. However, evidence from low-income settings remains sparse. We examined the associations of BF status at 6 months with anthropometry, body composition (BC), and cardiometabolic markers at 5 years in Ethiopian children. (2) Methods: Mother-child pairs from the iABC birth cohort were categorised into four BF groups at 6 months: 1. "Exclusive", 2. "Almost exclusive", 3. "Predominantly" and 4. "Partial or none". The associations of BF status with anthropometry, BC, and cardiometabolic markers at 5 years were examined using multiple linear regression analyses in three adjustment models. (3) Results: A total of 306 mother-child pairs were included. Compared with "Exclusive", the nonexclusive BF practices were associated with a lower BMI, blood pressure, and HDL-cholesterol at 5 years. Compared with "Exclusive", "Predominantly" and "Almost exclusive" had shorter stature of -1.7 cm (-3.3, -0.2) and -1.2 cm (-2.9, 0.5) and a lower fat-free mass index of -0.36 kg/m2 (-0.71, -0.005) and -0.38 kg/m2 (-0.76, 0.007), respectively, but a similar fat mass index. Compared with "Exclusive", "Predominantly" had higher insulin of 53% (2.01, 130.49), "Almost exclusive" had lower total and LDL-cholesterol, and "Partial or none" had a lower fat mass index. (5) Conclusions: Our data suggest that children exclusively breastfed at 6 months of age are overall larger at 5 years, with greater stature, higher fat-free mass but similar fat mass, higher HDL-cholesterol and blood pressure, and lower insulin concentrations compared with predominantly breastfed children. Long-term studies of the associations between BF and metabolic health are needed to inform policies.

Growth and Body Composition 5 y After Treatment for Severe Acute Malnutrition: A 5-y Prospective Matched Cohort Study in Ethiopian Children.

BACKGROUND: Short-term anthropometric outcomes are well documented for children treated for severe acute malnutrition (SAM). However, anthropometric recovery may not indicate restoration of healthy body composition. OBJECTIVES: This study aimed to evaluate long-term associations of SAM with growth and body composition of children 5 y after discharge from community-based management of acute malnutrition (CMAM). METHODS: We conducted a 5-y prospective cohort study, enrolling children aged 6 to 59 mo discharged from CMAM (post-SAM) (n = 203) and nonmalnourished matched controls (n = 202) from Jimma Zone, Ethiopia in 2013. Anthropometry and body composition (bioelectrical impedance) were assessed. Multiple linear regression models tested differences in height-for-age (HAZ), weight-for-age (WAZ), and body mass index-for-age (BAZ) z-scores; height-adjusted fat-free mass index (FFMI); and FM index (FMI) between groups. RESULTS: Post-SAM children had higher stunting prevalence than controls at discharge (82.2% compared with 36.0%; P < 0.001), 1 y (80.2% compared with 53.7%; P < 0.001), and 5 y postdischarge (74.2% compared with 40.8%; P < 0.001). Post-SAM children remained 5 cm shorter throughout follow-up, indicating no HAZ catch-up. No catch-up in WAZ or BAZ was observed. Post-SAM children had lower hip (-2.05 cm; 95% CI: -2.73, -1.36), waist (-0.92 cm; CI: -1.59, -0.23) and mid-upper arm (-0.64 cm; CI: -0.90, -0.42) circumferences and lower-limb length (-1.57 cm; 95% CI: -2.21, -0.94) at 5 y postdischarge. They had larger waist-hip (0.02 cm; 95% CI: 0.008, 0.033) and waist-height (0.013 cm; 95% CI: 0.004, 0.021) ratios, and persistent deficits in FFMI at discharge and 6 mo and 5 y postdischarge (P < 0.001 for all). No difference was detected in head circumference, sitting height, or FMI. CONCLUSIONS: Five y after SAM treatment, children maintained deficits in HAZ, WAZ, BAZ, and FFMI, with preservation of FMI, sitting height, and head circumference at the expense of lower-limb length, indicating a "thrifty growth" pattern. Research is urgently needed to identify effective clinical and public health interventions to mitigate these consequences of malnutrition.

Maternal capital predicts investment in infant growth and development through lactation.

Introduction: Maternal capital (MC) is a broad term from evolutionary biology, referring to any aspects of maternal phenotype that represent resources available for investment in offspring. We investigated MC in breastfeeding mothers of late preterm and early term infants, examining its relationship with infant and breastfeeding outcomes. We also determined whether MC modified the effect of the relaxation intervention on these outcomes. Methods: The data was collected as part of a randomized controlled trial investigating breastfeeding relaxation in 72 mothers of late preterm and early term infants. Indicators of MC (socioeconomic, social, somatic, reproductive, psychological, and cognitive) were collected at baseline at 2-3 weeks post-delivery. Principal Component Analysis was conducted for the MC measures and two components were identified: 1."Subjective" maternal capital which included stress and depression scores, and 2."Objective" maternal capital which included height, infant birth weight, and verbal memory. Univariate linear regression was conducted to assess the relationship between objective and subjective MC (predictors) and infant growth, infant behavior, maternal behavior, and infant feeding variables (outcomes) at 6-8 weeks. The interaction of MC and intervention assignment with outcomes was assessed. Results: Higher objective MC was significantly associated with higher infant weight (0.43; 95%CI 0.21,0.66) and length z-scores (0.47; 95%CI 0.19,0.76), shorter duration of crying (-17.5; 95%CI -33.2,-1.9), and lower food (-0.28; 95%CI -0.48,-0.08) and satiety responsiveness (-0.17; 95%CI -0.31,-0.02) at 6-8 weeks. It was also associated with greater maternal responsiveness to infant cues (-0.05, 95%CI -0.09,-0.02 for non-responsiveness). Greater subjective maternal capital was significantly associated with higher breastfeeding frequency (2.3; 95%CI 0.8,3.8) and infant appetite (0.30; 95%CI 0.07,0.54). There was a significant interaction between the intervention assignment and objective MC for infant length, with trends for infant weight and crying, which indicated that the intervention had greater effects among mothers with lower capital. Conclusion: Higher MC was associated with better infant growth and shorter crying duration. This was possibly mediated through more frequent breastfeeding and prompt responsiveness to infant cues, reflecting greater maternal investment. The findings also suggest that a relaxation intervention was most effective among those with low MC, suggesting some reduction in social inequalities in health.

Association of linear growth velocities between 0 and 6 years with kidney function and size at 10 years: A birth cohort study in Ethiopia.

BACKGROUND: Risk of noncommunicable diseases accrues from fetal life, with early childhood growth having an important role in adult disease risk. There is a need to understand how early-life growth relates to kidney function and size. OBJECTIVES: This study aimed to assess the association of linear growth velocities among children between 0 and 6 y with kidney function and size among children aged 10 y. METHODS: The Ethiopian Anthropometric and Body Composition birth cohort recruited infants born at term to mothers living in Jimma with a birth weight of ≥1500 g and without congenital malformations. Participants were followed up with 13 measurements between birth and 6 y of age. The latest follow-up was at ages 7-12 y with measurement of serum cystatin C as a marker of kidney function and ultrasound assessment of kidney dimensions. Kidney volume was computed using an ellipsoid formula. Linear-spline multilevel modeling was used to compute linear growth velocities between 0 and 6 y. Multiple linear regression modeling was used to examine the associations of linear growth velocities in selected age periods with cystatin C and kidney size. RESULTS: Data were captured from 355 children, at a mean age of 10 (range 7-12) y. The linear growth velocity was high between 0 and 3 mo and then decreased with age. There was no evidence of an association of growth velocity ≤24 mo with cystatin C at 10 y. Between 24 and 48 and 48 and 76 mo, serum cystatin C was higher by 2.3% [95% confidence interval (CI): 0.6, 4.2] and 2.1% (95% CI: 0.3, 4.0) for 1 SD higher linear growth velocity, respectively. We found a positive association between linear growth velocities at all intervals between 0 and 6 y and kidney volume. CONCLUSIONS: Greater linear growth between 0 and 6 y of development was positively associated with kidney size, and greater growth velocity after 2 y was associated with higher serum cystatin C concentrations.

An evolutionary perspective on social inequality and health disparities: Insights from the producer-scrounger game.

There is growing concern with social disparities in health, whether relating to gender, ethnicity, caste, socio-economic position or other axes of inequality. Despite addressing inequality, evolutionary biologists have had surprisingly little to say on why human societies are prone to demonstrating exploitation. This article builds on a recent book, 'The Metabolic Ghetto', describing an overarching evolutionary framework for studying all forms of social inequality involving exploitation. The dynamic 'producer-scrounger' game, developed to model social foraging, assumes that some members of a social group produce food, and that others scrounge from them. An evolutionary stable strategy emerges when neither producers nor scroungers can increase their Darwinian fitness by changing strategy. This approach puts food systems central to all forms of human inequality, and provides a valuable lens through which to consider different forms of gender inequality, socio-economic inequality and racial/caste discrimination. Individuals that routinely adopt producer or scrounger tactics may develop divergent phenotypes. This approach can be linked with life history theory to understand how social dynamics drive health disparities. The framework differs from previous evolutionary perspectives on inequality, by focussing on the exploitation of foraging effort rather than inequality in ecological resources themselves. Health inequalities emerge where scroungers acquire different forms of power over producers, driving increasing exploitation. In racialized societies, symbolic categorization is used to systematically assign some individuals to low-rank producer roles, embedding exploitation in society. Efforts to reduce health inequalities must address the whole of society, altering producer-scrounger dynamics rather than simply targeting resources at exploited groups.

Natural selection and human adiposity: crafty genotype, thrifty phenotype.

Evolutionary perspectives on obesity have aimed to understand how the genetic constitution of individuals has been shaped by selective pressures such as famine, predation or infectious disease. The dual intervention model assumes strong selection on lower and upper limits of adiposity, but negligible fitness implications for intermediate adiposity. These frameworks are agnostic to age, sex and condition. I argue that selection has favoured a 'crafty genotype'-a genetic basis for accommodating variability in the 'fitness value' of fat through phenotypic plasticity, depending on the endogenous and exogenous characteristics of each individual. Hominin evolution occurred in volatile environments. I argue that the polygenetic basis of adiposity stabilizes phenotype in such environments, while also coordinating phenotypic variance across traits. This stability underpins reaction norms through which adiposity can respond sensitively to ecological factors. I consider how the fitness value of fat changes with age, sex and developmental experience. Fat is also differentially distributed between peripheral and abdominal depots, reflecting variable prioritization of survival versus reproduction. Where longevity has been compromised by undernutrition, abdominal fat may promote immediate survival and fitness, while long-term cardiometabolic risks may never materialize. This approach helps understand the sensitivity of adiposity to diverse environmental factors, and why the health impacts of obesity are variable. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part I)'.

Human energetic stress associated with upregulation of spatial cognition.

OBJECTIVES: Evolutionary life history theory has a unique potential to shed light on human adaptive capabilities. Ultra-endurance challenges are a valuable experimental model allowing the direct testing of phenotypic plasticity via physiological trade-offs in resource allocation. This enhances our understanding of how the body prioritizes different functions when energetically stressed. However, despite the central role played by the brain in both hominin evolution and metabolic budgeting, cognitive plasticity during energetic deficit remains unstudied. MATERIALS: We considered human cognitive plasticity under conditions of energetic deficit by evaluating variability in performance in three key cognitive domains. To achieve this, cognitive performance in a sample of 48 athletes (m = 29, f = 19) was assessed before and after competing in multiday ultramarathons. RESULTS: We demonstrate that under conditions of energetic deficit, performance in tasks of spatial working memory (which assessed ability to store location information, promoting landscape navigation and facilitating resource location and calorie acquisition) increased. In contrast, psychomotor speed (reaction time) remained unchanged and episodic memory performance (ability to recall information about specific events) decreased. DISCUSSION: We propose that prioritization of spatial working memory performance during conditions of negative energy balance represents an adaptive response due to its role in facilitating calorie acquisition. We discuss these results with reference to a human evolutionary trajectory centred around encephalisation. Encephalisation affords great plasticity, facilitating rapid responses tailored to specific environmental conditions, and allowing humans to increase their capabilities as a phenotypically plastic species.

Maternal mental health and economic autonomy in lowland rural Nepal: Do parents-in-law provide constraint or support?

Background and objectives: In patrilocal societies, married women typically co-reside with their parents-in-law, who may act in their son's reproductive interests. These relationships may shape maternal mental health and autonomy. Few studies have examined these dynamics from an evolutionary perspective. Theoretically, marital kin may increase their fitness by increasing maternal investment or by reducing paternity uncertainty. We explored how co-residence with parents-in-law and husband is associated with maternal outcomes to evaluate whether marital kin provide support or constraint. Methodology: We analysed data from 444 households in rural lowland Nepal. Maternal mental health was assessed by General Health Questionnaire. Logistic regression models investigated whether, relative to mothers living with both husband and parents-in-law, those co-resident with other combinations of relatives had poorer mental health and lower household economic autonomy (decision-making, bargaining power), adjusting for socio-economic confounders. Results: Co-residence with husband only, or neither husband nor parents-in-law, was associated with higher odds of mothers reporting feeling worthless and losing sleep but also earning income and making household expenditure decisions. Husband co-residence was associated with overall maternal distress but also with less unpaid care work and greater decision-making responsibility. There were no differences in maternal outcomes for mothers living with parents-in-law only, relative to those living with both husbands and parents-in-law. Conclusions and implications: Co-residence of parents-in-law and husbands was associated with contrasting patterns of maternal mental health and economic autonomy. We suggest that different marital kin place different economic demands on mothers, while restricting their autonomy in different ways as forms of 'mate-guarding'.

Low birthweight is associated with a higher incidence of type 2 diabetes over two decades independent of adult BMI and genetic predisposition.

AIMS/HYPOTHESIS: Low birthweight is a risk factor for type 2 diabetes. Most previous studies are based on cross-sectional prevalence data, not designed to study the timing of onset of type 2 diabetes in relation to birthweight. We aimed to examine associations of birthweight with age-specific incidence rate of type 2 diabetes in middle-aged to older adults over two decades. METHODS: Adults aged 30-60 years enrolled in the Danish Inter99 cohort in 1999-2001 (baseline examination), with information on birthweight from original birth records from 1939-1971 and without diabetes at baseline, were eligible. Birth records were linked with individual-level data on age at diabetes diagnosis and key covariates. Incidence rates of type 2 diabetes as a function of age, sex and birthweight were modelled using Poisson regression, adjusting for prematurity status at birth, parity, polygenic scores for birthweight and type 2 diabetes, maternal and paternal diabetes history, socioeconomic status and adult BMI. RESULTS: In 4590 participants there were 492 incident type 2 diabetes cases during a mean follow-up of 19 years. Type 2 diabetes incidence rate increased with age, was higher in male participants, and decreased with increasing birthweight (incidence rate ratio [95% CI per 1 kg increase in birthweight] 0.60 [0.48, 0.75]). The inverse association of birthweight with type 2 diabetes incidence was statistically significant across all models and in sensitivity analysis. CONCLUSIONS/INTERPRETATION: A lower birthweight was associated with increased risk of developing type 2 diabetes independent of adult BMI and genetic risk of type 2 diabetes and birthweight.

Effect of preterm birth on growth and blood pressure in adulthood in the Pelotas 1993 cohort.

BACKGROUND: Preterm birth has been associated with increased risk of hypertension and cardiovascular disease later in adulthood, attributed to cardiovascular and metabolic alterations in early life. However, there is paucity of evidence from low- and middle-income countries (LMICs). METHODS: We investigated the differences between preterm (<37 weeks gestational age) and term-born individuals in birth length and weight as well as adult (18 and 20 years) height, weight and blood pressure in the Brazilian 1993 Pelotas birth cohort using linear regressions. Analyses were adjusted for the maternal weight at the beginning of pregnancy and maternal education and family income at childbirth. Additional models were adjusted for body mass index (BMI) and birthweight. Separate analyses were run for males and females. The complete sample was analysed with an interaction term for sex. RESULTS: Of the 3585 babies included at birth, 3010 were followed up in adulthood at 22 years. Preterm participants had lower length and weight at birth. This difference remained for male participants in adulthood, but female participants were no shorter than their term counterparts by 18 years of age. At 22 years, females born preterm had lower blood pressures (systolic blood pressure -1.00 mmHg, 95%CI -2.7, 0.7 mmHg; diastolic blood pressure -1.1 mmHg, 95%CI -2.4, 0.3 mmHg) than females born at term. These differences were not found in male participants. CONCLUSIONS: In this Brazilian cohort we found contrasting results regarding the association of preterm birth with blood pressure in young adulthood, which may be unique to an LMIC.

Stress and resilience during pregnancy: A comparative study between pregnant and non-pregnant women in Ethiopia.

BACKGROUND: Stress during pregnancy is associated with perturbances in maternal psychology and physiology, and results in adverse pregnancy and birth outcomes. However, little attention has been given to understand maternal stress and its potential negative consequences in many low- and middle-income countries. We aimed to investigate whether pregnancy is associated with greater stress and lower psychological resilience among women living in Jimma, Southwest Ethiopia. METHOD: An institution-based comparative cross-sectional study design was implemented in Jimma University Medical Center and Jimma health centers from 15 September to 30 November 2021. Women attending antenatal care and family planning services were invited to participate in the study. Participants were interviewed using the Perceived Stress Scale (PSS-10), Brief Resilience Scale (BRS), distress questionnaire-5, and the Household Food Insecurity Access Scale (HFIAS). Linear regression analysis was used to test associations between pregnancy (exposure) and outcomes of interest (stress and resilience scores), while adjusting for potential confounders. Stress and resilience were mutually adjusted for one another in the final model. RESULTS: A total of 166 pregnant and 154 non-pregnant women participated, with mean age of 27.0 SD 5.0 and 29.5 SD 5.3 years respectively. Pregnancy was associated with increased stress score by 4.1 points (ß = 4.1; 95% CI: 3.0, 5.2), and with reduced resilience by 3.3 points (ß = -3.3; 95% CI: -4.5, -2.2) in a fully adjusted model. In mutually-adjusted models, pregnancy was independently associated with greater stress (ß = 2.9, 95% CI 1.8, 3.9) and lower resilience (ß = -1.3, 95% CI: -2.5, -0.2) compared to non-pregnant women. CONCLUSION: In this low income setting, pregnancy is associated with greater vulnerability in the mental health of women, characterized by greater perceived stress and diminished resilience. Context-relevant interventions to improve resilience and reduce stress could help improve the health and wellbeing of mothers, with potential benefits for their offspring.

Patterns of energy allocation during energetic scarcity; evolutionary insights from ultra-endurance events.

Exercise physiologists and evolutionary biologists share a research interest in determining patterns of energy allocation during times of acute or chronic energetic scarcity. Within sport and exercise science, this information has important implications for athlete health and performance. For evolutionary biologists, this would shed new light on our adaptive capabilities as a phenotypically plastic species. In recent years, evolutionary biologists have begun recruiting athletes as study participants and using contemporary sports as a model for studying evolution. This approach, known as human athletic palaeobiology, has identified ultra-endurance events as a valuable experimental model to investigate patterns of energy allocation during conditions of elevated energy demand, which are generally accompanied by an energy deficit. This energetic stress provokes detectable functional trade-offs in energy allocation between physiological processes. Early results from this modelsuggest thatlimited resources are preferentially allocated to processes which could be considered to confer the greatest immediate survival advantage (including immune and cognitive function). This aligns with evolutionary perspectives regarding energetic trade-offs during periods of acute and chronic energetic scarcity. Here, we discuss energy allocation patterns during periods of energetic stress as an area of shared interest between exercise physiology and evolutionary biology. We propose that, by addressing the ultimate "why" questions, namely why certain traits were selected for during the human evolutionary journey, an evolutionary perspective can complement the exercise physiology literature and provide a deeper insight of the reasons underpinning the body's physiological response to conditions of energetic stress.

Long-term trends in human body size track regional variation in subsistence transitions and growth acceleration linked to dairying.

Evidence for a reduction in stature between Mesolithic foragers and Neolithic farmers has been interpreted as reflective of declines in health, however, our current understanding of this trend fails to account for the complexity of cultural and dietary transitions or the possible causes of phenotypic change. The agricultural transition was extended in primary centers of domestication and abrupt in regions characterized by demic diffusion. In regions such as Northern Europe where foreign domesticates were difficult to establish, there is strong evidence for natural selection for lactase persistence in relation to dairying. We employ broad-scale analyses of diachronic variation in stature and body mass in the Levant, Europe, the Nile Valley, South Asia, and China, to test three hypotheses about the timing of subsistence shifts and human body size, that: 1) the adoption of agriculture led to a decrease in stature, 2) there were different trajectories in regions of in situ domestication or cultural diffusion of agriculture; and 3) increases in stature and body mass are observed in regions with evidence for selection for lactase persistence. Our results demonstrate that 1) decreases in stature preceded the origins of agriculture in some regions; 2) the Levant and China, regions of in situ domestication of species and an extended period of mixed foraging and agricultural subsistence, had stable stature and body mass over time; and 3) stature and body mass increases in Central and Northern Europe coincide with the timing of selective sweeps for lactase persistence, providing support for the "Lactase Growth Hypothesis."

The Long-Term Consequences of Early Life Exposure to Tsunami and Conflict on Adolescents in Sri Lanka.

The consequences for adolescent health due to early life exposure to natural disasters combined with war are not known. We collected data from adolescents aged 12-13 years in Sri Lanka whose mothers were pregnant during the Indian Ocean tsunami in 2004 in a tsunami-affected region (n = 22), conflict-affected region (n = 35), conflict-plus-tsunami-affected region (n = 29), or controls in areas unaffected by either (n = 24). Adjusted body mass index (BMI)-for-age z-scores were 1.3, 1.0 and 2.0 for conflict, tsunami, and conflict-plus-tsunami, respectively, compared with the control group. Greater skinfold thickness and higher diastolic blood pressure were found in adolescents born in the conflict zone but no differences were found in height, head circumference, and waist circumference, or blood results, with the exception of serum insulin. Being born after a natural disaster or during conflict was associated with increased BMI and body fat during adolescent, which are associated with longer-term risk of noncommunicable disease.