L S Sugiyama
Biographic Data
| ID | 4598 |
|---|---|
| NAME | L S Sugiyama |
| GIVEN NAMES | L S |
| FAMILY NAME | Sugiyama |
| SIGNATURE | SUGIYAMA L S |
| AFFILIATIONS | University of Oregon |
| ORCID | 0000-0003-1279-0006 |
| VERIFIED | Yes |
| TOTAL WORKS | 41 |
| TOTAL CITATIONS | 152 |
| AUTHOR COUNT | 41 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2001 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 6 |
Market Integration and Reproductive Transitions Among Indigenous Shuar and Neighboring Nonindigenous Ecuadorians in Amazonian Ecuador
OBJECTIVE: Global reproductive transitions are well documented, yet less is known about how neighboring populations with divergent histories and exposure to market integration (MI) experience them. This study examines how sociocultural and economic proxies of MI predict variation in reproductive outcomes among indigenous Shuar and nonindigenous Ecuadorian mestizos (Colonos) from Amazonian Ecuador, focusing on menarcheal age, age at first birth, p…
Navigating Practical, Political, and Ethical Challenges of Long‐Term Human Biology Field Research
Major advances in understanding human biology and health have been made possible by long‐term field research projects with Indigenous peoples, whose ecological settings and lifeways are distinct from majority populations in high‐income settings. Long‐term fieldwork is central to human biology, yet much about this research approach remains opaque. This paper considers a single long‐term study—the Shuar Health and Life History Project in Amazonian …
Impaired Intestinal Function Among Indigenous Shuar Children of Amazonian Ecuador
Intestinal function appears to be considerably impaired among school-age Shuar children living in a low-resource, rural setting. Children living in unsanitary, non-industrialized contexts may routinely experience intestinal permeability-related immune activation and malabsorption-related energy/nutrient loss. More research is needed to explore the breadth of global variation in children's intestinal function and to investigate its many evolutiona…
The Shuar Health and Life History Project
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.) imp…
Oxidative Stress and Its Relationship With Market Integration and Pathogen Exposure Among Indigenous Shuar Children of Amazonian Ecuador
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
Soil‐Transmitted Helminths and the Intricacies of Immunoregulation
OBJECTIVES: The old friends hypothesis (OFH) examines connections between the global increase in immunoregulatory diseases (e.g., allergy and autoimmunity) and reduced exposure to immune-priming symbionts like soil-transmitted helminths. Helminth species, however, vary in their effects on hosts and should be considered separately. We examined relationships between species-specific helminth infection and circulating biomarkers of adaptive immune a…
Somatic Symptoms Are Associated With Elevated Blood Pressure and Epstein–Barr Virus Antibodies Among Shuar of the Ecuadorian Amazon
INTRODUCTION: This study tests the hypothesis that self-reported somatic symptoms are associated with biomarkers of stress, including elevated blood pressure and suppressed immune function, among Shuar adults living in the Ecuadorian Amazon. METHODS: Research was conducted in three Shuar communities in the Upano Valley of the Ecuadorian Amazon and included the collection of biomarkers and a structured morbidity interview. Participants self-report…
Testosterone, 8‐Oxo‐2′‐Deoxyguanosine (8‐OHdG) and Cu/Zn Superoxide Dismutase (SOD) in Adult Shuar Males of Amazonian Ecuador
Objectives Reproductive effort incurs the cost of biological aging and morbidity by compromising somatic maintenance when key resources are limited. Oxidative stress is positively correlated with reproductive effort in adult human females and non‐human male animal models, but human males are understudied. We hypothesized that due to its anabolic and metabolic promotion of reproductive effort in human males, testosterone would be positively associ…
Circulating Epstein–Barr Virus Antibody Levels as a Biomarker of Socioecological Adversity in Amazonian Ecuador
OBJECTIVES: Circulating Epstein-Barr virus antibodies (EBV-Ab) are used as a biomarker of chronic stress in high-income settings, but their relevance in environments with a high burden of infectious disease, nutritional constraints, and limited resources is less clear. We investigated EBV-Ab as a biomarker of adversity in a setting where local ecology and economy may affect immune development differently than in wealthy countries. METHODS: We mea…
Salivary Testosterone, Age, and Adiposity Associations Among Shuar Males in Amazonian Ecuador Challenge Assumptions of “Normal” Testosterone Patterns
Objectives Adult male testosterone concentrations in high income countries often decrease with age and adiposity, a pattern typically viewed as “normal.” However, testosterone is expected to be adaptively regulated within the range of resource constrained, high pathogen, natural fertility conditions across which it evolved to function. We therefore examine associations among testosterone diurnal variation, age, and adiposity among Indigenous Shua…
Variation in diurnal cortisol patterns among the Indigenous Shuar of Amazonian Ecuador
This study expands the documented range of global variation in HPA axis activity and diurnal cortisol production and provides important insights into the plasticity of human stress physiology across diverse developmental and socioecological settings
Cognitive foundations for helping and harming others
Low prevalence of anemia among Shuar communities of Amazonian Ecuador
OBJECTIVE: Anemia is an important global health challenge. We investigate anemia prevalence among Indigenous Shuar of Ecuador to expand our understanding of population-level variation, and to test hypotheses about how anemia variation is related to age, sex, and market integration. METHODS: Hemoglobin levels were measured in a total sample of 1650 Shuar participants (ages 6 months to 86 years) from 46 communities between 2008 and 2017 to compare …
Age‐related patterns of cytomegalovirus antibodies accompanying Epstein‐Barr virus co‐infection
OBJECTIVE: Cytomegalovirus (CMV) infection is associated with age-related chronic disease, and co-infection with Epstein-Barr virus (EBV) may compound disease risk. We aimed to assess the frequency of CMV infection and its relationship with age among EBV seropositive individuals in an Indigenous Amazonian population. METHODS: We report concentrations of CMV and EBV antibodies in dried blood spot samples collected from 157 EBV positive Shuar parti…
Bringing the lab bench to the field
Point‐of‐care testing (POCT) allows researchers and health‐care providers to bring the lab bench to the field, providing essential health information that can be leveraged to improve health care, accessibility, and understanding across clinical and research settings. Gaps in health service access are most pronounced in what we term RIR settings—rural/remote regions, involving Indigenous peoples, and/or within resource‐limited settings. In these c…
Lassitude
Validation of an enzyme‐linked immunoassay assay for osteocalcin, a marker of bone formation, in dried blood spots
OBJECTIVES: Investigating factors that contribute to bone loss and accretion across populations in remote settings is challenging, particularly where diagnostic tools are scarce. To mitigate this challenge, we describe validation of a commercial ELISA assay to measure osteocalcin, a biomarker of bone formation, from dried blood spots (DBS). METHODS: We validated the Osteocalcin Human SimpleStep ELISA kit from Abcam (ab1951214) using 158 matched p…
Variability of C‐reactive protein in first‐generation Ecuadorian immigrants living in the United States
The variability of CRP levels in individuals with relatively high childhood pathogen exposure is comparable to previously reported studies in North America and Europe. However, CRP values are relatively low. CRP is an appropriate measure of subacute inflammation in this sample
Disparities in bone density across contemporary Amazonian forager‐horticulturalists
OBJECTIVES: This study investigates bone density across the life course among Bolivian Tsimane and Ecuadorian Shuar of Amazonia. Both groups are rural, high-fertility forager-horticulturalists, with high lifetime physical activity levels. We test whether Tsimane and Shuar bone density patterns are different from each other, and if both groups are characterized by lower osteoporosis risk compared to U.S. references. METHODS: Anthropometric and cal…
In Memoriam
A dried blood spot‐based method to measure levels of tartrate‐resistant acid phosphatase 5b (TRACP‐5b), a marker of bone resorption
OBJECTIVES: A number of basic questions about bone biology have not been answered, including population differences in bone turnover. In part, this stems from the lack of validated minimally invasive biomarker techniques to measure bone formation and resorption in field-based population-level research. The present study addresses this gap by validating a fingerprick dried blood spot (fDBS) assay for tartrate-resistant acid phosphatase 5b (TRACP-5…
High energy requirements and water throughput of adult Shuar forager‐horticulturalists of Amazonian Ecuador
OBJECTIVES: We measured total energy expenditure (TEE; kcal/d) and water throughput (L/d) among Shuar forager-horticulturalists from Amazonian Ecuador to compare their daily energy and water demands to adults in other small-scale and industrialized populations. METHODS: TEE and water throughput were measured using the doubly labeled water method among 15 Shuar adults (eight women, seven men; age range 18-60 years) living in a relatively remote vi…
Soil‐transmitted helminth infection and intestinal inflammation among the Shuar of Amazonian Ecuador
OBJECTIVES: Little research exists documenting levels of intestinal inflammation among indigenous populations where exposure to macroparasites, like soil-transmitted helminths (STHs), is common. Reduced STH exposure is hypothesized to contribute to increased prevalence of elevated intestinal inflammation in wealthy nations, likely due to coevolutionary histories between STHs and human immune systems that favored anti-inflammatory pathways. Here, …
Tradeoffs between immune function and childhood growth among Amazonian forager-horticulturalists
Significance The energetic impact of immune function on human growth remains unclear. Using data from Amazonian forager-horticulturalists, we show that diverse, low-level immune activity predicts reduced childhood growth over periods of competing energy use ranging from 1 wk to 20 mo. We also demonstrate that modest body fat stores (i.e., energy reserves) protect children from the particularly detrimental impact of acute inflammation on growth. T…
Coalitional Play Fighting and the Evolution of Coalitional Intergroup Aggression
Implications of market integration for cardiovascular and metabolic health among an indigenous Amazonian Ecuadorian population
This study provides evidence that MI among Shuar is not a uniformly negative process but instead produces complex cardiovascular and metabolic health outcomes
Illness, injury, and disability among Shiwiar forager‐horticulturalists
Human life history is distinguished by long lifespan, delayed reproduction, intergenerational asymmetric benefit transfers from adults to juveniles and between adults, and a large brain able to engage in unprecedented levels of learning, reasoning, and insight. The evolution of these traits depends on relatively low human mortality. Understanding why humans have low mortality is therefore critical for understanding the evolution of key human trai…
Heterogeneous effects of market integration on sub-adult body size and nutritional status among the Shuar of Amazonian Ecuador
This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth and health among the Shuar and other indigenous Amazonian populations
Living with Kin in Lowland Horticultural Societies
Postmarital residence patterns in traditional human societies figure prominently in models of hominid social evolution with arguments for patrilocal human bands similar in structure to female-dispersal systems in other African apes. However, considerable flexibility in hunter-gatherer cultures has led to their characterization as primarily multilocal. Horticulturalists are associated with larger, more sedentary social groups with more political i…
Disparities in bone density across contemporary Amazonian forager‐horticulturalists
OBJECTIVES: This study investigates bone density across the life course among Bolivian Tsimane and Ecuadorian Shuar of Amazonia. Both groups are rural, high-fertility forager-horticulturalists, with high lifetime physical activity levels. We test whether Tsimane and Shuar bone density patterns are different from each other, and if both groups are characterized by lower osteoporosis risk compared to U.S. references. METHODS: Anthropometric and cal…
Soil‐transmitted helminth infection and intestinal inflammation among the Shuar of Amazonian Ecuador
OBJECTIVES: Little research exists documenting levels of intestinal inflammation among indigenous populations where exposure to macroparasites, like soil-transmitted helminths (STHs), is common. Reduced STH exposure is hypothesized to contribute to increased prevalence of elevated intestinal inflammation in wealthy nations, likely due to coevolutionary histories between STHs and human immune systems that favored anti-inflammatory pathways. Here, …
Social roles, prestige, and health risk
Coalitional Play Fighting and the Evolution of Coalitional Intergroup Aggression
The application of knemometry to measure childhood short‐term growth among the indigenous Shuar of Ecuador
OBJECTIVES: Knemometry, the precise measurement of lower leg (LL) length, suggests that childhood short-term (e.g., weekly) growth is a dynamic, nonlinear process. However, owing to the large size and complexity of the traditional knemometer device, previous study of short-term growth among children has been restricted predominantly to clinical settings in industrialized Western nations. The aim of the present study is to address this limitation …
Evolutionary psychology
Evolutionary psychology
Social roles, prestige, and health risk
Is beauty in the context-sensitive adaptations of the beholder?
Illness, injury, and disability among Shiwiar forager‐horticulturalists
Human life history is distinguished by long lifespan, delayed reproduction, intergenerational asymmetric benefit transfers from adults to juveniles and between adults, and a large brain able to engage in unprecedented levels of learning, reasoning, and insight. The evolution of these traits depends on relatively low human mortality. Understanding why humans have low mortality is therefore critical for understanding the evolution of key human trai…
Growth and market integration in Amazonia
We describe and compare the growth of three groups of juveniles, aged 0–18, who experience different degrees of market integration and acculturation in the Ecuadorian Amazon. These include 1,384 indigenous Shuar from the Upano Valley of Ecuador and surrounding areas, 570 nonindigenous colono (or colonist) children from the same area, and 42 Shiwiar from the interior of Ecuador. We use differences between these populations in National Health and N…
Life history, immune function, and intestinal helminths
Objectives. Infection with helminths is associated with shifts in host immunity, including increased production of immunoglobulin E (IgE) and reduced inflammation. Given limited energy budgets, these shifts may involve changes in energy allocation toward competing demands. Here we test for potential trade‐offs between growth, IgE, and the inflammatory marker C‐reactive protein (CRP). Methods. Dried blood spots and anthropometrics were collected f…
Physical activity in an indigenous Ecuadorian forager‐horticulturalist population as measured using accelerometry
OBJECTIVE: Minimal information on physical activity is available for non-Western populations undergoing the transition to a market economy. This is unfortunate given the importance of these data for understanding health issues such as the global obesity epidemic. We consider the utility of using accelerometry technology to examine activity patterns and energy use regulation among indigenous Shuar, an Ecuadorian forager-horticulturalist population…
Reproductive effects on skeletal health in Shuar women of Amazonian Ecuador
OBJECTIVE: Clinical and epidemiological research suggest that bone mineral density (BMD) in women is shaped by various reproductive factors such as parity and lactation patterns. However, the extent of these effects on BMD remains unclear because of contradictory findings and a focus on industrialized populations. Because fertility patterns in these groups are vastly different than those of women from non-Western, subsistence populations, our cur…
Analysis of variability of high sensitivity C‐reactive protein in lowland ecuador reveals no evidence of chronic low‐grade inflammation
This study is the first to investigate CRP variability in a nonindustrialized, high infectious disease environment. It documents a pattern of variation over time that is distinct from prior research, with no evidence for chronic low-grade inflammation. These results may have substantial implications for research on inflammation and diseases of aging globally, as well as for scientific understandings of the regulation of inflammation
Implications of market integration for cardiovascular and metabolic health among an indigenous Amazonian Ecuadorian population
This study provides evidence that MI among Shuar is not a uniformly negative process but instead produces complex cardiovascular and metabolic health outcomes
Living with Kin in Lowland Horticultural Societies
Postmarital residence patterns in traditional human societies figure prominently in models of hominid social evolution with arguments for patrilocal human bands similar in structure to female-dispersal systems in other African apes. However, considerable flexibility in hunter-gatherer cultures has led to their characterization as primarily multilocal. Horticulturalists are associated with larger, more sedentary social groups with more political i…
Determining osteoporosis risk in older C olono adults from rural A mazonian E cuador using calcaneal ultrasonometry
OBJECTIVE: Low bone density and osteoporosis prevalence, while well-documented in wealthy nations, are poorly studied in rural, non-clinical contexts in economically developing regions such as Latin America. This study contributes preliminary osteoporosis risk data for a rural Colono (mestizo) population from Amazonian Ecuador. METHODS: Anthropometrics were collected for 119 adult participants (74 females, 45 males [50-90 years old]). Heel bone d…
Physical growth of the shuar
OBJECTIVES: Information concerning physical growth among small-scale populations remains limited, yet such data are critical to local health efforts and to foster basic understandings of human life history and variation in childhood development. Using a large dataset and robust modeling methods, this study aims to describe growth from birth to adulthood among the indigenous Shuar of Amazonian Ecuador. METHODS: Mixed-longitudinal measures of heigh…
The application of knemometry to measure childhood short‐term growth among the indigenous Shuar of Ecuador
OBJECTIVES: Knemometry, the precise measurement of lower leg (LL) length, suggests that childhood short-term (e.g., weekly) growth is a dynamic, nonlinear process. However, owing to the large size and complexity of the traditional knemometer device, previous study of short-term growth among children has been restricted predominantly to clinical settings in industrialized Western nations. The aim of the present study is to address this limitation …
Heterogeneous effects of market integration on sub-adult body size and nutritional status among the Shuar of Amazonian Ecuador
This study provides novel insight into the complex socio-ecological pathways linking MI, physical growth and health among the Shuar and other indigenous Amazonian populations
Tradeoffs between immune function and childhood growth among Amazonian forager-horticulturalists
Significance The energetic impact of immune function on human growth remains unclear. Using data from Amazonian forager-horticulturalists, we show that diverse, low-level immune activity predicts reduced childhood growth over periods of competing energy use ranging from 1 wk to 20 mo. We also demonstrate that modest body fat stores (i.e., energy reserves) protect children from the particularly detrimental impact of acute inflammation on growth. T…
Coalitional Play Fighting and the Evolution of Coalitional Intergroup Aggression
A dried blood spot‐based method to measure levels of tartrate‐resistant acid phosphatase 5b (TRACP‐5b), a marker of bone resorption
OBJECTIVES: A number of basic questions about bone biology have not been answered, including population differences in bone turnover. In part, this stems from the lack of validated minimally invasive biomarker techniques to measure bone formation and resorption in field-based population-level research. The present study addresses this gap by validating a fingerprick dried blood spot (fDBS) assay for tartrate-resistant acid phosphatase 5b (TRACP-5…
High energy requirements and water throughput of adult Shuar forager‐horticulturalists of Amazonian Ecuador
OBJECTIVES: We measured total energy expenditure (TEE; kcal/d) and water throughput (L/d) among Shuar forager-horticulturalists from Amazonian Ecuador to compare their daily energy and water demands to adults in other small-scale and industrialized populations. METHODS: TEE and water throughput were measured using the doubly labeled water method among 15 Shuar adults (eight women, seven men; age range 18-60 years) living in a relatively remote vi…
Soil‐transmitted helminth infection and intestinal inflammation among the Shuar of Amazonian Ecuador
OBJECTIVES: Little research exists documenting levels of intestinal inflammation among indigenous populations where exposure to macroparasites, like soil-transmitted helminths (STHs), is common. Reduced STH exposure is hypothesized to contribute to increased prevalence of elevated intestinal inflammation in wealthy nations, likely due to coevolutionary histories between STHs and human immune systems that favored anti-inflammatory pathways. Here, …
Lassitude
Validation of an enzyme‐linked immunoassay assay for osteocalcin, a marker of bone formation, in dried blood spots
OBJECTIVES: Investigating factors that contribute to bone loss and accretion across populations in remote settings is challenging, particularly where diagnostic tools are scarce. To mitigate this challenge, we describe validation of a commercial ELISA assay to measure osteocalcin, a biomarker of bone formation, from dried blood spots (DBS). METHODS: We validated the Osteocalcin Human SimpleStep ELISA kit from Abcam (ab1951214) using 158 matched p…
Variability of C‐reactive protein in first‐generation Ecuadorian immigrants living in the United States
The variability of CRP levels in individuals with relatively high childhood pathogen exposure is comparable to previously reported studies in North America and Europe. However, CRP values are relatively low. CRP is an appropriate measure of subacute inflammation in this sample
Disparities in bone density across contemporary Amazonian forager‐horticulturalists
OBJECTIVES: This study investigates bone density across the life course among Bolivian Tsimane and Ecuadorian Shuar of Amazonia. Both groups are rural, high-fertility forager-horticulturalists, with high lifetime physical activity levels. We test whether Tsimane and Shuar bone density patterns are different from each other, and if both groups are characterized by lower osteoporosis risk compared to U.S. references. METHODS: Anthropometric and cal…
Biology (21 works) · Medicine (19 works) · Population (16 works) · Ecology (14 works) · Indigenous (14 works) · Indigenous Health and Education (14 works) · Demography (13 works) · Amazon rainforest (11 works) · Child Nutrition and Water Access (10 works) · Environmental health (10 works)