American Journal of Human Biology最新文献

{"title":"Navigating Change: Biocultural Dimensions of Feeding in a Pilagá Community Undergoing Lifestyle and Economic Transition in Argentina\u0000 Navegando el cambio: Dimensiones bioculturales de la alimentación en una comunidad Pilagá en transición económica y de estilo de vida en Argentina","authors":"Sofia I. Olmedo,&nbsp;Claudia R. Valeggia,&nbsp;Cecilia Palavecino,&nbsp;Rafael Pérez-Escamilla","doi":"10.1002/ajhb.70200","DOIUrl":"10.1002/ajhb.70200","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>This research analyzed the interplay between diet and sociocultural influences in the food consumption patterns of the Pilagá people in Formosa, Argentina.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This cross-sectional mixed-methods study, conducted in 2023, included all 59 family clusters in a Pilagá community. Food intake was assessed using three 24-h dietary recalls per household, while qualitative data were collected through semi-structured interviews, free-listing exercises, and participant observation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Dietary habits in the Pilagá community were notably limited in variety and nutritional content, with 71% of participants reporting they ate just two meals a day. Purchased white bread, water, and infusions were consumed daily. Despite the high proportion of processed foods, the diet shows some foraged wild food. Food holds multifaceted roles beyond its biological function, with traditional foods valued not only for nourishment but also for their perceived health benefits and cultural significance.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This Pilagá community is experiencing a dietary transition toward westernized foods, driven by biosociocultural factors that mirror broader shifts in local food systems and consumption patterns.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146158894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating Measures of Pollutant Exposure in Human Biology Research","authors":"Lawrence M. Schell,&nbsp;Mia V. Gallo","doi":"10.1002/ajhb.70210","DOIUrl":"10.1002/ajhb.70210","url":null,"abstract":"<div>\u0000 \u0000 <p>This toolkit paper describes the value of including pollutant measurements in human biology research and describes considerations to implement such research. Human biologists study populations that are exposed to a variety of pollutants including metals and organic compounds used in agriculture and pest control. These pollutants can affect biological outcomes investigated by human biologists. Considering the impact of one or more of these pollutants in our investigations involves careful attention to properties of each pollutant and how the body metabolizes and stores them. Assessing exposure to many metals and organic compounds is best done by bio-sampling, usually of blood, but other media include hair, fingernails, and urine. Appropriate sampling media differ by pollutant but many found in the bloodstream may be collected together though not necessarily stored in the same way and not analyzed in the laboratory by the same method. A team approach is recommended as specialized knowledge of the proper sampling, handling, and analysis of each toxicant is needed. Choosing a laboratory should consider at a minimum the range of congeners measured, the minimum detection level, and the turnaround time for results required for the analysis. Study participants are likely to be interested in their toxicant exposure. The distribution of results should include careful description and interpretation to allow non-scientists to understand and take action if needed. Litigation by study participants against polluters is possible making it necessary to scrupulously preserve records of collection and analysis for possible court subpoena.</p>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70210","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146133621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Not All Stress Is the Same: Variable Associations Between Psychosocial Stressors and Urinary Cortisol Rhythms in a Small-Scale Subsistence Society","authors":"Dominik C. Jud,&nbsp;Valerie Baettig,&nbsp;Abigail E. Colby,&nbsp;Charlotte Debras,&nbsp;Camila Scaff,&nbsp;Benjamin C. Trumble,&nbsp;Lorin Hutchings,&nbsp;Michael D. Baumgarten,&nbsp;Arnulfo Cary Ista,&nbsp;Adrian V. Jaeggi","doi":"10.1002/ajhb.70205","DOIUrl":"10.1002/ajhb.70205","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Objectives&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Dysregulations of the hypothalamic–pituitary–adrenal (HPA) axis have been linked to adverse health outcomes such as obesity, cardiovascular disease, and diabetes. While research on the HPA axis is growing, few studies have examined whether different types of stressors affect HPA functioning differently, and none have done so in small-scale subsistence populations. To do so, we measured HPA axis activity and various kinds of stressors among the Tsimane of Bolivia, a population with more traditional lifestyles and stressors including low caloric intake, social conflict, and market integration.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Participants were adults from three different Tsimane communities (&lt;i&gt;n&lt;/i&gt; = 129, 57% women). For each participant, urinary cortisol (&lt;i&gt;n&lt;/i&gt;&lt;sub&gt;samples&lt;/sub&gt; = 303), corrected for specific gravity, was measured once at waking and at least once later on the same day to measure the diurnal slope. One hundred and twenty-five participants completed a questionnaire on culturally relevant psychosocial stressors in the Tsimane such as food insecurity, social conflicts, and economic problems. Multilevel Bayesian multivariate models assessed associations between stressor scores and cortisol levels.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Diurnal variation in the HPA axis was differentially associated with each type of stressor. Food insecurity was associated with higher morning levels (median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;intercept&lt;/sub&gt; = 0.08, &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&gt; 0&lt;/sub&gt;= 0.73) and a steeper diurnal slope (median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;slope&lt;/sub&gt; = −0.19, &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&lt; 0&lt;/sub&gt; = 0.83), while economic problems were associated with lower waking levels and shallower slopes (median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;intercept&lt;/sub&gt; = −0.05; &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&lt; 0&lt;/sub&gt; = 0.64, median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;slope&lt;/sub&gt; = 0.12, &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&gt; 0&lt;/sub&gt;= 0.72). Higher morning levels and steeper slopes were also associated with better self-rated health (median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;intercept&lt;/sub&gt; = 0.06; &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&lt; 0&lt;/sub&gt; = 0.66, median &lt;i&gt;r&lt;/i&gt;&lt;sub&gt;slope&lt;/sub&gt; = −0.10, &lt;i&gt;p&lt;/i&gt; &lt;sub&gt;&gt; 0&lt;/sub&gt; = 0.71).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusion&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;While many of these associations had high statistical uncertainty due to wide posterior distributions, the results overall emphasize complex relationships between perceived stressors and diurnal cortisol rhythms among a small-scale subsistence-based society. Future work employing longitudinal designs and higher-resolution sampling will be needed to clarify these trends.&lt;/p&gt;\u0000 ","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12879915/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146127201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ribcage Morphology in Native South American Populations From Different Altitudes: Insights From a Global Comparative Framework","authors":"J. M. López-Rey,&nbsp;M. D. D’Angelo del Campo,&nbsp;G. Bettera Marcat,&nbsp;M. Arrieta,&nbsp;M. Fabra,&nbsp;S. Salega,&nbsp;P. Mercolli,&nbsp;V. Seldes,&nbsp;D. García-Martínez,&nbsp;M. Bastir","doi":"10.1002/ajhb.70211","DOIUrl":"10.1002/ajhb.70211","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>Altitude shapes human morphology as highland populations must cope with cold and hypoxic environments. Although Andean highlanders have been proposed to exhibit larger and deeper ribcages, this idea is mainly based on research using disarticulated skeletal elements or non-South American controls. The objective of this research is to study 3D ribcage configuration of native South American populations considering altitude and worldwide ribcage variation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Ribcages of 37 adult South Americans (17 highlanders, 20 lowlanders) were reconstructed and analyzed using 3D geometric morphometrics. Shape variation was assessed through Procrustes MANOVA and PCA, while centroid size was used to test for size differences. Comparisons were also made with a sample of 92 adult worldwide lowlanders.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>South American highlanders and lowlanders show similar ribcage shapes, both exhibiting a deeper thorax than worldwide lowlanders. No significant differences in absolute ribcage size were detected between South American highlanders and lowlanders. However, a marked sexual dimorphism was observed in both groups, with males having wider and significantly larger ribcages than females.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The pronounced ribcage depth in native South Americans could represent a population-specific trait maintained through long-term interactions, potentially advantageous in high-altitude settings but neutral in the lowlands. In addition, we propose that South American highlanders have a larger ribcage relative to their smaller body size compared to lowlanders. Finally, the larger and stockier male ribcage morphology in South Americans supports the notion of greater respiratory capacity and metabolic demands in males.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12869005/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146114854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Shuar Health and Life History Project: Overview at 20 Years and Introduction to the Special Issue","authors":"Samuel S. Urlacher,&nbsp;Theresa E. Gildner,&nbsp;Lawrence S. Sugiyama","doi":"10.1002/ajhb.70207","DOIUrl":"10.1002/ajhb.70207","url":null,"abstract":"<p>The Shuar Health and Life History Project (established in 2005) is an interdisciplinary, integrated field and laboratory research project with the Indigenous Shuar population in Amazonian Ecuador. Grounded in human biology, behavioral ecology, evolutionary psychology, evolutionary medicine, and global health, the SHLHP has three key research foci: (1) To identify how market integration (via effects on diet, pathogen exposure, lifestyle, etc.) impacts Shuar health and well-being; (2) To investigate (using evolutionary life history theory) how lifetime phenotype and health are shaped by adaptive energy allocation between competing life tasks; and (3) To test hypothesized human psychological and demographic adaptations, including aspects of sociality that are central to the evolutionary success of our species. To address these foci, the SHLHP has established long-term and mutually beneficial relationships with the Shuar and local collaborators, resulting in community-engaged data collection with more than 3500 participants and a wide range of research publications and policy contributions over the past 20 years. This special issue of the <i>American Journal of Human Biology</i> showcases 10 original SHLHP articles that span much of the project's intellectual breadth and represent important advances for understanding human biology, life history, and health. To serve as an introduction, here we provide essential background on the Shuar and the SHLHP, overview the ten included special issue articles, and discuss key research and impact goals for the next 20 years of the SHLHP.</p>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12865669/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146108176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Metacarpophalangeal Pattern Profile: An Old Method With New Insights Into the Evaluation of Short Stature","authors":"Marcelo Damaso Maruichi,&nbsp;Bruno Telma Destailleur,&nbsp;Giulia Maesta Apelbaum,&nbsp;Carlos Alberto Longui,&nbsp;Cristiane Kochi","doi":"10.1002/ajhb.70212","DOIUrl":"10.1002/ajhb.70212","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>To characterize the metacarpophalangeal pattern profile (MCPP) of healthy children and adolescents from São Paulo, Brazil, and to establish percentile curves by chronological age (CA), bone age (BA), and sex using the LMS method. Additionally, to compare these findings with previous population-based data and to apply the derived standards to patients with skeletal dysplasias.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Left hand and wrist radiographs were obtained from healthy individuals and age-matched patients with confirmed skeletal dysplasias. Tubular bone lengths were compared across CA and BA, against prior normative studies, and with dysplastic cohorts using Student's <i>t</i>-test. Patient Z-scores were calculated from LMS parameters generated from the healthy population.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>We analyzed 974 radiographs from healthy subjects and 83 from patients (18 hypochondroplasia, 27 achondroplasia, 14 osteogenesis imperfecta, 24 Turner syndrome). In healthy participants, hand bone lengths correlated significantly with CA and BA. Compared with international reference data, differences in mean metacarpal and phalangeal lengths were noted. Patients with achondroplasia and hypochondroplasia exhibited markedly reduced Z-scores relative to controls, whereas those with Turner syndrome showed reductions of up to 1.8 SD in the fourth metacarpal. Patients with osteogenesis imperfecta demonstrated no significant deviations.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This study established MCPP reference percentiles for Brazilian children and adolescents using the LMS method. Bone measurements showed consistent associations with CA and BA. Although differences were observed relative to international cohorts, the generated standards effectively discriminated dysplastic phenotypes, particularly achondroplasia and hypochondroplasia, supporting the use of MCPP analysis as an adjunct tool for evaluating short stature and suspected skeletal dysplasias.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12862513/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146100942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Racial and Ethnic Differences in Bone Mass in Pediatric Populations: A Systematic Review","authors":"Tiago Rodrigues de Lima,&nbsp;Mateus Augusto Bim,&nbsp;Jean Carlos Parmigiani De Marco,&nbsp;Isadora Gonzaga,&nbsp;Clair Costa Miranda,&nbsp;Andreia Pelegrini","doi":"10.1002/ajhb.70204","DOIUrl":"10.1002/ajhb.70204","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>The purpose of this study was to summarize the evidence regarding possible differences in areal bone mineral density (aBMD) and bone mineral content (BMC) across racial and ethnic groups of children and adolescents.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A systematic review was conducted using five electronic databases, supplemented by complementary searches of reference lists. Studies should have used dual-energy x-ray absorptiometry to assess bone mass in children and adolescents (aged ≤ 19 years) with no special clinical conditions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Of the 1791 articles initially identified, 26 were included. Whites had lower aBMD/BMC than Blacks in 60.2% (47/78) of the analyzed results. In racial/ethnic groups that did not include Blacks, aBMD/BMC values were lower when compared to Blacks or ethnic groups that included Blacks in 80.0% (8/10) of possible results. Most findings indicated a paucity of evidence regarding differences in aBMD/BMC between Whites and Asians, Pacific Islanders, Hispanics, and Mexican-Americans (percentage of results ≤ 50.0%).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Based on the findings, it can be concluded that White children and adolescents have lower bone mass values compared to their Black peers. Racial and ethnic groups that do not include Black individuals also exhibit lower bone mass values compared to Black children and adolescents. Additionally, there appears to be no difference in bone mass between White children and adolescents and their Asian, Pacific Islander, Hispanic, and Mexican-American counterparts.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 2","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146100986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidative Stress and Its Relationship With Market Integration and Pathogen Exposure Among Indigenous Shuar Children of Amazonian Ecuador","authors":"Anna Samsonov,&nbsp;J. Josh Snodgrass,&nbsp;Melissa A. Liebert,&nbsp;Felicia C. Madimenos,&nbsp;Elizabeth Y. Kim,&nbsp;Marcela Pfaff Nash,&nbsp;Lawrence S. Sugiyama,&nbsp;Samuel S. Urlacher","doi":"10.1002/ajhb.70206","DOIUrl":"10.1002/ajhb.70206","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>Oxidative stress (OS) plays a key role in human aging and lifelong health. Problematically, little attention has been given to OS during childhood or outside of wealthy, industrialized populations. This limits understanding of the lifestyle and environmental factors that may drive global variation in childhood OS. Here, we present multifaceted urinary OS data from Indigenous Shuar children of Amazonian Ecuador to examine how children's OS is influenced by: (1) broad differences in market integration (MI; rural vs. peri-urban living); (2) household-level predictors of pathogen exposure; and (3) physiological measures of pathogen burden (immune activity) and adversity (cortisol).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Anthropometrics, household questionnaire data, and biospecimens (urine and finger-prick dried blood spots) were collected cross-sectionally from rural (<i>n</i> = 43) and peri-urban (<i>n</i> = 34) Shuar children, ages 4–12 years. 8-hydroxy-2′-deoxyguanosine (8-OHdG; a measure of oxidative damage) and total antioxidant capacity were measured in urine, and the overall oxidative stress index (OSI) was calculated. Predictors of OS were assessed using regression models.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Peri-urban Shuar children had, on average, 45% lower OSI than rural children (<i>p</i> = 0.002). Household pathogen exposure variables, including lack of running water and a greater number of resident individuals, predicted greater child OS (multiple <i>p</i> &lt; 0.05). Children's physiological measures of pathogen burden (circulating total immunoglobulin E) and adversity (urinary cortisol) similarly predicted greater OS (multiple <i>p</i> &lt; 0.05).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>These findings suggest that MI, including its impact on pathogen exposure and physiology, is an important driver of global variation in childhood OS and related disparities in phenotype and health.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12837346/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146054847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduced Fat Oxidation as a Potential Pathway Linking Early-Life Adversity to Obesity Risk: Evidence From Vanuatu","authors":"Md. Khaled Bin Oli Bhuiyan,&nbsp;Patrick Baca,&nbsp;Elena Hinz,&nbsp;Eddy Kiel,&nbsp;Krishna K. Kotra,&nbsp;Peter Mattison,&nbsp;Amanda McGrosky,&nbsp;Denise Mercado,&nbsp;Herman Pontzer,&nbsp;Cecilia M. T. Sena,&nbsp;Mary C. Towner,&nbsp;Katherine Wander,&nbsp;Ian J. Wallace,&nbsp;Siobhán M. Cully","doi":"10.1002/ajhb.70208","DOIUrl":"10.1002/ajhb.70208","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>Adverse environmental conditions during early life can increase the risk of obesity in adulthood, but the underlying mechanisms are not completely understood. Here, we test the hypothesis that early-life adversity leads to a lower metabolic rate and reduced fat oxidation, factors expected to increase fat accumulation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We used data collected from 80 children and adolescents (aged 6–15 years; <i>n</i> = 39 females) living in Vanuatu. Relative lower limb length, calculated as the ratio of lower limb length to stature, was used as a surrogate measure of each individual's early-life environmental conditions, with a shorter relative lower limb length considered indicative of greater adversity. Fasting resting metabolic rate (RMR) and respiratory quotient (RQ) were measured with indirect calorimetry, and a higher RQ value was considered indicative of a lower rate of fat oxidation.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>We found that, in a linear mixed-effects model including age, sex, and fat-free body mass as fixed effects and community and family as random effects, relative lower limb length was not significantly associated with RMR (<i>p</i> = 0.95). However, in a separate model, relative lower limb length was significantly negatively associated with RQ (<i>p</i> = 0.036), after accounting for the same fixed and random effects.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>The latter finding suggests that adverse environmental conditions during early life may lead to reduced fat oxidation, which has the potential to increase the risk of obesity later in life. This finding might partially explain the so-called double burden of malnutrition (the co-occurrence of undernutrition and obesity) currently affecting many low- and middle-income countries.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146041656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic Ancestry Reveals Historical Diversity of Formation Across Three Brazilian Communities of African Descent (Quilombos) in Central Brazil","authors":"Sabrina Guimarães Paiva,&nbsp;Anna C. Rivara,&nbsp;Matheus de Castro Nóbrega,&nbsp;Rafaela de Cesare Parmezan Toledo,&nbsp;Maria de Nazaré Klautau-Guimarães,&nbsp;Sidney Emanuel Batista dos Santos,&nbsp;Lorena Madrigal,&nbsp;Silviene Fabiana de Oliveira","doi":"10.1002/ajhb.70199","DOIUrl":"https://doi.org/10.1002/ajhb.70199","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Introduction</h3>\u0000 \u0000 <p>Characterized as relatively isolated communities, many Brazilian <i>quilombos</i> were formed during the period of slavery in Brazil when enslaved persons (most of African descent) ran away or were abandoned by their enslavers. <i>Quilombos</i> in Central Brazil, whose settlement was more recent due to the relative isolation of the region, remain understudied. To address this gap, this study estimated the genetic ancestry of three <i>quilombo</i> communities in Central Brazil.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A cross-sectional study was performed among three Central Brazilian <i>quilombos</i>, Cocalinho (<i>N</i> = 54) and Pé do Morro (<i>N</i> = 58) located in the Brazilian state of Tocantins, and Kalunga (<i>N</i> = 132) located in the state of Goiás. Genetic ancestry was estimated from 61 Ancestry-informative INDEL biallelic markers collected from blood samples and analyzed using STRUCTURE v 2.3. Statistical analyses were performed using SAS statistical software, v. 9.4.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The population demonstrated heterogeneous genetic admixture by <i>quilombo</i>. Average African admixture estimates were 36.75%, 29.82%, and 63.17% in Cocalinho (semirural), Pé do Morro (urban), and Kalunga (rural) communities, respectively. Indigenous and European ancestry contributions also varied by <i>quilombo</i>, with participants from the more recently populated <i>quilombos</i> and those living closest to urban areas having higher European and Indigenous genetic ancestry contributions.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study demonstrates that <i>quilombos</i> comprise rich population histories shaped by culture, historical events, and sociodemographic and environmental interactions. By unraveling the genetic tapestry of Central Brazil's <i>quilombos</i>, this study contributes to a deeper understanding of Brazil's intricate social and historical landscape.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"38 1","pages":""},"PeriodicalIF":1.7,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70199","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146096579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}