American Journal of Human Biology最新文献

{"title":"Political Liberation, Hope, and Social Competition Are the Motor of Secular Trends in Height","authors":"Christiane Scheffler,&nbsp;Detlef Groth,&nbsp;Michael Hermanussen","doi":"10.1002/ajhb.70095","DOIUrl":"https://doi.org/10.1002/ajhb.70095","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Long-term improvements in physical living conditions correlate with long-term trends in height.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Aim</h3>\u0000 \u0000 <p>To link temporal characteristics of the secular trend in height with the simultaneous political and economic dynamics.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Sample and Methods</h3>\u0000 \u0000 <p>Height of men of the German Armed Forces born between 1865 and 1975 was correlated with indicators of economic prosperity (GDP), nutrition and health (infant mortality), and indicators of social inhomogeneity (income inequality and household wealth share). The time periods before 1916, between 1916 and 1933, 1947, 1973, and after 1989 were separately analyzed. Coherence analysis was used to assess the changes in the temporal trends.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Mean height of young adult men increased by 0.45 mm/year (before 1916), by 2.15 mm/year (1916–1933), by 1.87 mm/year in the early Federal Republic of Germany (FRG) until 1973, by 1.45 mm/year in the late FRG, and by 4 mm/year in East German conscripts after the reunification in 1989. The most substantial height increments occurred in periods of political upheaval and loss of state authority.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The nonlinear pattern of secular height increments in Germany since the late 19th century suggests that political liberation, hope for a better life, and illusions of equity, freedom, justice, and the expectation of social advancement are associated with competitive growth, strategic growth adjustments, and finally, long-term and substantial secular trends in height.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144519780","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":"Evaluation of the Relationship Between Aggression and Digit Ratio Through a Cross-Sectional Study Among Hitit University Students","authors":"Fırat Koç","doi":"10.1002/ajhb.70098","DOIUrl":"https://doi.org/10.1002/ajhb.70098","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;The second-to-fourth digit ratio (2D:4D) is widely recognized as a biomarker of prenatal testosterone exposure and has been previously linked to aggression. This association demonstrates sex-specific variability and is further modulated by both biological and environmental influences. The present study aims to examine the relationship between 2D:4D and levels of aggression, including subtypes of aggression, among university students of Turkish ethnic origin residing in the Central Black Sea region of Turkey. Additionally, the study explores sex differences in these associations.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Method&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;This cross-sectional study included 203 undergraduate students (108 females, 95 males) from Hitit University. Participants not affiliated with the university were excluded. The 2D:4D were measured using a digital caliper, and aggression levels were assessed using the Buss–Perry Aggression Questionnaire (BPAQ). Statistical analyses comprised the Mann–Whitney &lt;i&gt;U&lt;/i&gt; test, Kruskal–Wallis test, and Spearman correlation analysis.&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;In females, significant yet weak negative correlations were found between the lengths of the right-hand 2D, right-hand 4D, and left-hand 4D and both physical and verbal aggression scores (&lt;i&gt;p&lt;/i&gt; &lt; 0.05; &lt;i&gt;r&lt;/i&gt; = 0.20–0.39). A weak negative correlation was also observed between the right-hand 4D and the total BPAQ score (&lt;i&gt;p&lt;/i&gt; = 0.024, &lt;i&gt;r&lt;/i&gt; = −0.218). Furthermore, weak positive correlations were identified between the left-hand 2D:4D and both physical aggression and total aggression scores. Among males, weak but significant positive correlations were identified between the right-hand 2D length and the left-hand 2D:4D and anger subscale scores (&lt;i&gt;p&lt;/i&gt; = 0.043, &lt;i&gt;p&lt;/i&gt; = 0.009; &lt;i&gt;r&lt;/i&gt; = 0.20–0.39). Similarly, weak positive correlations were observed between the right-hand 2D and 2D:4D and hostility subscale scores (&lt;i&gt;p&lt;/i&gt; = 0.031; &lt;i&gt;r&lt;/i&gt; = 0.20–0.39). Additionally, a weak negative correlation was found between the right-hand 4D and verbal aggression (&lt;i&gt;p&lt;/i&gt; = 0.017, &lt;i&gt;r&lt;/i&gt; = −0.244). Finally, a weak but significant positive correlation was detected between the right-hand 2D:4D and the total BPAQ score (&lt;i&gt;p&lt;/i&gt; = 0.012, &lt;i&gt;r&lt;/i&gt; = 0.28).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusions&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;The findings indicate that digit ratio does not exhibit marked sexual dimorphism; however, the expression of aggressive behavior appears to differ by sex. In females, shorter digit lengths (2D and 4D) are negatively associated with specific subdimensions of aggression, whereas in males, higher 2D:4D","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503168","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":"Sex Ratio at Birth in Northern Ireland During the COVID-19 Pandemic: A Comparison With Published Data From the Republic of Ireland, England and Wales","authors":"Gwinyai Masukume,&nbsp;Peyton Cleaver,&nbsp;Roy K. Philip,&nbsp;Victor Grech,&nbsp;Amy L. Non","doi":"10.1002/ajhb.70099","DOIUrl":"https://doi.org/10.1002/ajhb.70099","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objectives</h3>\u0000 \u0000 <p>The COVID-19 pandemic has been linked in several countries to fluctuations in the proportion of male live births/total live births, known as the sex ratio at birth (SRB). This study investigates how the pandemic influenced SRB patterns in Northern Ireland compared to published data from neighboring regions, including the Republic of Ireland with which it shares an open land border, and England and Wales, across the sea.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Monthly live birth data for Northern Ireland from 2015 to 2021 were obtained from the Northern Ireland Statistics and Research Agency. A time series analysis predicted the SRB for 2020 using data from 2015 to 2019. Predicted and observed SRB values were compared for 2020.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In August 2020, 5 months after the pandemic declaration, the SRB fell significantly to 49.13%, the period's lowest, below the 95% prediction interval (50.09%–51.85%). In December 2020, 9 months after the declaration, the SRB rose to 54.48%, exceeding the prediction interval (49.75%–51.57%). This overall SRB pattern resembled that in England and Wales but differed from the Republic of Ireland.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The decline in SRB in August 2020, occurring 3–5 months after the pandemic declaration, suggests the pandemic disproportionately affected male fetuses in Northern Ireland. The rise in December, 9 months after the declaration, may relate to increased sexual activity in March 2020 following lockdown in a subset of the population. Northern Ireland's SRB pattern aligns more with England and Wales than the Republic of Ireland, indicating that socio-political ties in the United Kingdom may be more influential for pandemic response than geographical proximity.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503097","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":"Market Integration and Secular Changes in Anthropometric Characteristics in Two Maya Communities From Yucatan, Mexico","authors":"Hugo Azcorra,&nbsp;María Teresa Castillo-Burguete,&nbsp;Julio Lara-Riegos,&nbsp;Valery Sarabia-Herrera,&nbsp;Juan Carlos Salazar-Rendón,&nbsp;Nina Mendez-Dominguez,&nbsp;C. Marjorie Aelion,&nbsp;Thomas Leatherman","doi":"10.1002/ajhb.70100","DOIUrl":"https://doi.org/10.1002/ajhb.70100","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Objective</h3>\u0000 \u0000 <p>To compare the changes in children's height, weight, and BMI from two Maya communities during 1986–2023 in order to analyze if their differences in degrees of participation in market economy are reflected in secular changes in growth measures.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Material and Methods</h3>\u0000 \u0000 <p>We compared the changes in height, weight, and BMI of 1463 children (6–12 years) from two communities (Dzeal and Yalcoba) differing by speed and degree of market integration along three points in time: 1986/1987, 1996–1998/2000 and 2022/2023. Linear regression models were adjusted to estimate the changes in height-for-age (HAZ) and BMI-for-age <i>Z</i>-scores (BMIZ) in each community by age group and sex using the period of measurement as the independent variable.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Increases in HAZ between 1986/1987 and 2022/2023 were greater in children from the community with slower integration into the market economy (Dzeal). Differences in total increases between 1986/1987 and 2022/2023 in HAZ between communities were 0.50 (boys) and 1.19 (girls) standard deviations (SD) score in the 6–8-year-old group and 0.40 (boys) and 0.41 SD (girls) in children aged 9–12. Total increases in BMIZ were 0.81 SD (boys) and 1.07 SD (girls) in children (6–8 years) from the community with rapid integration (Yalcoba); changes in children with slower integration were not significant.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The rapid integration of the community into the market economy seems to favor larger secular increases in children's BMI and smaller increases in linear growth.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 7","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144503096","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":"Defining and Using Gender/Sex in Human Biology: Where Are We? Where Should We Be?","authors":"Cindi SturtzSreetharan,&nbsp;L. Zachary DuBois,&nbsp;Alexandra Brewis","doi":"10.1002/ajhb.70093","DOIUrl":"https://doi.org/10.1002/ajhb.70093","url":null,"abstract":"<div>\u0000 \u0000 <p>Sex and gender categories are often used by human biologists in hypothesis generation, research design, data analysis, and interpretation. Many studies in human biology thus differentiate samples by “sex” and/or “gender.” But it is unclear to what extent, if any, these terms are defined or clearly operationalized. Through analysis of recent publications in the <i>American Journal of Human Biology</i> we assessed how these terms are defined and used in human biological research. Through systemic coding of the text of all original research studies published in <i>AJHB</i> in 2023, we identified inconsistencies in the definition and application of these terms. We find that sex and gender are often conflated and often lack a clear definition. In addition, the reader must glean definitions and methods of operationalization. We tie these observations to theories of language as social action— the idea that language represents experience, creates organization, and differentiates. Thus more precise gender/sex language use in research reporting increases precision in science, but also matters for dissemination of human biological research. We discuss pressing opportunities for human biologists to lead translational science writing by moving toward such precise yet nuanced uses of sex and gender in their research reporting.</p>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482159","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":"Correction to “Maximal Fat Oxidation Rate in Healthy Young Adults. Influence of Cardiorespiratory Fitness Level and Sex”","authors":"","doi":"10.1002/ajhb.70094","DOIUrl":"https://doi.org/10.1002/ajhb.70094","url":null,"abstract":"<p>Jaén-Carrillo, D., F. García-Pinillos, A. Plaza-Florido, et al. 2025. “Maximal Fat Oxidation Rate in Healthy Young Adults. Influence of Cardiorespiratory Fitness Level and Sex.” <i>American Journal of Human Biology</i> 37, no. 1: e24212. https://doi.org/10.1002/ajhb.24212.</p><p>In the Correspondence section, the institutional email has been added for the author Iván Fernández-Navarrete. This should have read:</p><p>Correspondence: Iván Fernández-Navarrete (<span>[email protected]</span>; <span>[email protected]</span>)</p><p>The funding statement for this article was missing. The below funding statement has been added to the article:</p><p>Open access funding enabled and organized by Universidad de Granada/CBUA.</p><p>We apologize for this error.</p>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70094","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482163","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":"Correction to “The American Journal of Human Biology” Articles","authors":"","doi":"10.1002/ajhb.70088","DOIUrl":"https://doi.org/10.1002/ajhb.70088","url":null,"abstract":"<p>L. P. Miranda, D. Henriques-Neto, F. I. Leitão, and A. B. de Lima, “Physical Fitness and Health Profile of Adolescents Living in Amazonas.” American Journal of Human Biology 37, no. 5 (2025): e70047. https://doi.org/10.1002/ajhb.70047.</p><p>L. de Lima Alves Paresque, J. de Bem Lignani, R. Arantes, et al., “Factors Associated With Anemia in Xavante Indigenous Children from Central Brazil.” American Journal of Human Biology 37, no. 5 (2025): e70049. https://doi.org/10.1002/ajhb.70049.</p><p>The funding statement for these articles was missing. The below funding statement has been added to the articles:</p><p>The Article Processing Charge for the publication of this research was funded by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) (ROR identifier: 00x0ma614).</p><p>We apologize for this error.</p>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70088","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144367235","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 Homo erectus Female Revisited","authors":"Leslie C. Aiello","doi":"10.1002/ajhb.70091","DOIUrl":"https://doi.org/10.1002/ajhb.70091","url":null,"abstract":"<p>The Energetic Consequences of Being a <i>Homo erectus</i> Female was published in the <i>American Journal of Human Biology</i> over two decades ago. This paper drew attention to the high body-size-related reproductive costs of an <i>H. erectus</i> female if she retained the same reproductive schedule of smaller-bodied earlier hominins modeled on the schedule for modern <i>Pan</i>. The main conclusion was that the energetic cost per offspring would be significantly reduced by adopting a modern human reproductive schedule with a shorter lactation period and an overall shorter interbirth interval. To make this possible and support the energetic requirements of the larger body size, there would have had to be a fundamental shift in subsistence behavior involving a higher-quality diet and intergenerational cooperation in food acquisition. This paper re-evaluates these conclusions based on recent energetic research developments. Although the modeling parameters have changed, the conclusions are still valid. Their implications are discussed in light of modern research on the increase in body and brain size and the evolution of cooperative subsistence behavior.</p>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70091","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144367238","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":"From Testosterone to Racialization to Knobby Knees: 15 Years of Gender/Sex","authors":"Sari M. van Anders","doi":"10.1002/ajhb.70090","DOIUrl":"https://doi.org/10.1002/ajhb.70090","url":null,"abstract":"<p>This paper discusses ~15 years of my research on gender/sex. I first discuss how “sex versus gender” is an overlay onto “nature versus nurture” ideologies, and the ways these are unempirical (if not anti-empirical), inaccurate, and unjust. I provide definitions of gender/sex, as well as gender and sex, and the pitfalls of “getting sex right” ideologies that aim to provide a singular universal definition of sex that belies its multiplicity, dynamism, and social situatedness. I discuss how these ideologies are often rooted in “bio/logics” that seek to define sex in ways that restrict human rights, especially for gender/sex minorities. I focus on my own research on testosterone (T) beyond masculinity that highlights the importance of gender/sex. This includes thinking about T in terms of social and biomaterial construction, including a “gender → T pathway” and “chronic gender”. I then describe how discussions of T are also rooted in racism, racialization, colonialism, and settler colonialism. In addition, I delineate how this makes not just for “sex versus gender” dichotomies and gender binaries, but ladders or helices that include gender/sex and race/ethnicity, among other social locations. I also point to gender/sex as an important lens for understanding bodily formations beyond T, that include a new “knobby knee hypothesis”. In discussing these topics, I focus on an array of important feminist science principles, including epistemic injustice, pre-theory, intersectionality, and diffraction. I close by discussing how gender/sex can provide an avenue for bioscientific research that is more empirical, accurate, and just.</p>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144339329","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":"Higher Resting Metabolism Is Associated With Increased Free Triiodothyronine Among Female Reindeer Herders in Northern Finland","authors":"Cara Ocobock,&nbsp;Ville Stenbäck,&nbsp;Alexandra M. Niclou,&nbsp;Päivi Soppela,&nbsp;Minna Turunen,&nbsp;Jaroslaw Walkowiak,&nbsp;Karl-Heinz Herzig","doi":"10.1002/ajhb.70092","DOIUrl":"https://doi.org/10.1002/ajhb.70092","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Thyroid hormones (TH) regulate metabolism and are shaped by environmental factors—ambient temperature in particular. Previous work among indigenous and non-indigenous populations in Russia revealed that there are seasonal shifts in TH dynamics such that total and free triiodothyronine (fT₃) and free thyroxine (fT₄) increase during winter. Elevated TH levels in these populations were positively correlated with the elevated resting metabolic rate (RMR) commonly seen among indigenous cold climate populations.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Here we examined the relationship between TH levels (fT3, fT4, and thyroid stimulating hormone) and resting metabolism among reindeer herders (<i>N</i> = 35) and office workers (<i>N</i> = 16) from northern Finland in January 2019 and February of 2023. RMR was measured using indirect calorimetry at both time points and a TH analysis was conducted from venous blood samples collected before RMR measurements in 2023 only.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Controlling for fat free mass, female reindeer herders had significantly higher RMRs than male reindeer herders and significantly higher RMRs than predictive equation estimates. Female herders also had significantly higher fT₃ and TSH than male herders and female officer workers. Female herders exhibited a significant positive correlation between fT₄ and RMR; significant correlations were not found among male herders or female office workers.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>This preliminary study demonstrates variation in the relationship between TH levels and resting metabolism among reindeer herders and office workers in Northern Finland. These results highlight potential sex-based differences in TH and metabolism dynamics, particularly among female reindeer herders, that require further research.</p>\u0000 </section>\u0000 </div>","PeriodicalId":50809,"journal":{"name":"American Journal of Human Biology","volume":"37 6","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/ajhb.70092","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144331835","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}