Ik People Research Articles

Isotopic estimates of sugar intake are related to chronic disease risk factors but not obesity in an Alaska native (Yup’ik) study population

BackgroundSugar intake may be causally associated with chronic disease risk, either directly or by contributing to obesity. However, evidence from observational studies is mixed, in part due to the error and bias inherent in self-reported measures of sugar intake. Objective biomarkers may clarify the relationship between sugar intake and chronic disease risk. We have recently validated a biomarker of sugar intake in an Alaska Native (Yup’ik) study population that incorporates red blood cell carbon and nitrogen isotope ratios in a predictive model.ObjectiveThis study tested associations of isotopic estimates of sugar intake with BMI, waist circumference (WC), and a broad array of other physiological and biochemical measures of chronic disease risk in Yup’ik people.Subjects/MethodsIn a cross-sectional sample of 1076 Yup’ik people, multiple linear regression was used to examine associations of sugar intake with BMI, WC and other chronic disease risk factors.ResultsIsotopic estimates of sugar intake were not associated with BMI (P = 0.50) or WC (P = 0.85). They were positively associated with blood pressure, triglycerides, and leptin, and inversely associated with total-, HDL- and LDL-cholesterol and adiponectin.ConclusionsIsotopic estimates of sugar intake were not associated with obesity, but were adversely associated with other chronic disease risk factors in this Yup’ik study population. This first use of stable isotope markers of sugar intake may influence recommendations for sugar intake by Yup’ik people; however, longitudinal studies are required to understand associations with chronic disease incidence.

CDKAL1 and HHEX are associated with type 2 diabetes‐related traits among Yup'ik people (在尤皮克人群中CDKAL1和HHEX与2型糖尿病相关特征有关)

AbstractBackgroundGenome‐wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) associated with type 2 diabetes (T2D), mainly among individuals of European ancestry. In the present study, we examined the frequency of these SNPs and their association with T2D‐related traits in an Alaska Native study population with a historically low prevalence of T2D. We also investigated whether dietary characteristics that may protect against T2D, such as n‐3 polyunsaturated fatty acid (PUFA) intake, modify these associations.MethodsIn 1144 Yup'ik people, we examined 17 SNPs repeatedly identified in GWAS for individual and cumulative associations with T2D‐related traits. Cumulative associations were evaluated using a genetic risk score (GRS) calculated by summing risk alleles. Associations were tested for interactions with sex, body mass index (BMI), and n‐3 PUFA intake.ResultsThe rs7754840 SNP in CDKAL1 is significantly associated with HbA1c (P = 0.00091). The rs5015480 SNP near HHEX is significantly associated (in opposite direction to that in Europeans) with a combined fasting glucose (FG) and HbA1c measure (P = 0.00046) and with homeostatic model assessment of β‐cell function (HOMA‐B; P = 0.0014). The GRS is significantly associated with FG and combined FG and HbA1c only when the HHEX SNP is dropped from the GRS. Associations are not modified by BMI or n‐3 PUFA intake.ConclusionOur results highlight the potential importance of CDKAL1 and HHEX in glucose homeostasis in this Alaska Native population with a low prevalence of T2D, and suggest that these loci should be examined in greater detail in this population.

Evidence for novel genetic loci associated with metabolic traits in Yup'ik people.

To identify genomic regions associated with fasting plasma lipid profiles, insulin, glucose, and glycosylated hemoglobin in a Yup'ik study population, and to evaluate whether the observed associations between genetic factors and metabolic traits were modified by dietary intake of marine derived omega-3 polyunsaturated acids (n-3 PUFA). A genome-wide linkage scan was conducted among 982 participants of the Center for Alaska Native Health Research study. n-3 PUFA intake was estimated using the nitrogen stable isotope ratio (δ(15) N) of erythrocytes. All genotyped SNPs located within genomic regions with LOD scores > 2 were subsequently tested for individual SNP associations with metabolic traits using linear models that account for familial correlation as well as age, sex, community group, and n-3 PUFA intake. Separate linear models were fit to evaluate interactions between the genotype of interest and n-3 PUFA intake. We identified several chromosomal regions linked to serum apolipoprotein A2, high density lipoprotein-, low density lipoprotein-, and total cholesterol, insulin, and glycosylated hemoglobin. Genetic variants found to be associated with total cholesterol mapped to a region containing previously validated lipid loci on chromosome 19, and additional novel peaks of biological interest were identified at 11q12.2-11q13.2. We did not observe any significant interactions between n-3 PUFA intake, genotypes, and metabolic traits. We have completed a whole genome linkage scan for metabolic traits in Native Alaskans, confirming previously identified loci, and offering preliminary evidence of novel loci implicated in chronic disease pathogenesis in this population.

The Carbon Isotope Ratio of Alanine in Red Blood Cells Is a New Candidate Biomarker of Sugar-Sweetened Beverage Intake

An objective dietary biomarker would help clarify the contribution of sugar-sweetened beverage (SSB) intake to obesity and chronic disease risk. Previous studies have proposed the carbon isotope ratio (δ13C) as a biomarker of SSB intake but found associations that were of modest size and confounded by other components of the diet. We investigated whether the δ13C values of nonessential amino acids (δ13CNEAA) in RBCs could provide valid biomarkers that are more specific to SSBs. We assessed the associations of RBC δ13CNEAA with SSB intake in a study population of 68 Yup'ik people, using gas chromatography/combustion/isotope ratio mass spectrometry to measure δ13CNEAA and four 24-h dietary recalls to assess intake. Among RBC nonessential amino acids, alanine δ13C (δ13Calanine) was strongly correlated with intake of SSBs, added sugar, and total sugar (r = 0.70, 0.59, and 0.57, respectively; P < 0.0001) but uncorrelated with other dietary sources of elevated δ13C. We also evaluated whether sweetener intake could be noninvasively assessed using hair δ13Calanine in a subset of the study population (n = 30). Hair δ13Calanine was correlated with RBC δ13Calanine (r = 0.65; P < 0.0001) and showed similar associations with SSB intake. These results show that δ13Calanine in RBCs provides a valid and specific biomarker of SSB intake for the Yup'ik population and suggest RBCs and hair δ13Calanine as candidate biomarkers of SSB intake for validation in the general U.S. population. Ultimately, these biomarkers could clarify our understanding of whether and how SSB intake contributes to chronic disease.

Simple anthropometrics are more correlated with health variables than are estimates of body composition in Yup'ik people

We aimed to: 1) evaluate the relationships between several indices of obesity with obesity-related risk factors; 2) compare the accuracy of body composition estimates derived from anthropometry and bioimpedance analysis (BIA) to estimates of body composition assessed by doubly-labeled water (DLW); and 3) establish equations for estimating fat mass (FM), fat-free mass (FFM), and percent body fat (PBF) in Yup’ik Eskimo people. Participants included 1056 adult Yup’ik People from 11 communities in Southwestern Alaska. In a substudy of 30 participants, we developed population-specific linear regression models for estimating FM, FFM, and PBF from anthropometrics, age, sex, and BIA against criterion measures derived from total body water assessed with DLW. These models were then used with the population cohort and we analyzed the relationships between obesity indices and several health-related and disease status variables: 1. fasting plasma lipids, 2. glucose, 3. HbA1c, 4. adiponectin, 5. blood pressure, 6) diabetes (DM), and 7) cerebrocoronary vascular disease (CCVD) which includes stroke and heart disease. The best model for estimating FM in the substudy used only three variables – sex, waist circumference (WC), and hip circumference and had multiple R2=0.9730. FFM and PBF were calculated from FM and body weight. WC and other anthropometrics were more highly correlated with a number of obesity-related risk factors than were direct estimates of body composition. We conclude that body composition in Yup’ik People can be accurately estimated from simple anthropometrics.

Obesity polymorphisms identified in genome‐wide association studies interact with n‐3 polyunsaturated fatty acid intake and modify genetic associations with adiposity phenotypes in Yup'ik people

n‐3 polyunsaturated fatty acids (n‐3 PUFAs) have anti‐obesity effects that may modulate risk of obesity, in part, through interactions with genetic factors. Genome‐wide association studies (GWAS) have identified genetic variants associated with BMI; however the extent to which these variants influence adiposity through interactions with n‐3 PUFAs is unknown. We evaluated 10 obesity GWAS SNPs for associations with adiposity phenotypes in a cross‐sectional sample of Yup'ik people (n=1073) and evaluated whether genetic associations with obesity were modulated by n‐3 PUFA intake. n‐3 PUFAs intake was estimated using nitrogen stable isotope ratios (δ15N) of red blood cells and genotype‐phenotype analyses were tested in linear models accounting for familial correlations. FTO was positively associated with percent body fat and ETV5 was negatively associated with hip and thigh circumference. A genetic risk score (GRS) was positively associated with adiposity. GRS interactions with n‐3 PUFAs modified the association with adiposity and accounted for more than twice the phenotypic variation (~1–2%), relative to GRS associations alone. GRS interactions with n‐3 PUFA intake potentiated the risk of fat accumulation among individuals with high obesity GRS. These data suggest the anti‐obesity effects of n‐ 3 PUFAs among Yup'ik people, in part, may be dependent upon an individual's genetic predisposition to obesity.

Obesity polymorphisms identified in genome-wide association studies interact with n-3 polyunsaturated fatty acid intake and modify the genetic association with adiposity phenotypes in Yup’ik people

n-3 Polyunsaturated fatty acids (n-3 PUFAs) have anti-obesity effects that may modulate risk of obesity, in part, through interactions with genetic factors. Genome-wide association studies (GWAS) have identified genetic variants associated with body mass index (BMI); however, the extent to which these variants influence adiposity through interactions with n-3 PUFAs remains unknown. We evaluated 10 highly replicated obesity GWAS single nucleotide polymorphisms (SNPs) for individual and cumulative associations with adiposity phenotypes in a cross-sectional sample of Yup'ik people (n=1,073) and evaluated whether genetic associations with obesity were modulated by n-3 PUFA intake. A genetic risk score (GRS) was calculated by adding the BMI-increasing alleles across all 10 SNPs. Dietary intake of n-3 PUFAs was estimated using nitrogen stable isotope ratio (δ(15)N) of red blood cells, and genotype-phenotype analyses were tested in linear models accounting for familial correlations. GRS was positively associated with BMI (p=0.012), PBF (p=0.022), ThC (p=0.025), and waist circumference (p=0.038). The variance in adiposity phenotypes explained by the GRS included BMI (0.7%), PBF (0.3%), ThC (0.7%), and WC (0.5%). GRS interactions with n-3 PUFAs modified the association with adiposity and accounted for more than twice the phenotypic variation (~1-2%), relative to GRS associations alone. Obesity GWAS SNPs contribute to adiposity in this study population of Yup'ik people and interactions with n-3 PUFA intake potentiated the risk of fat accumulation among individuals with high obesity GRS. These data suggest the anti-obesity effects of n-3 PUFAs among Yup'ik people may, in part, be dependent upon an individual's genetic predisposition to obesity.

Using exploratory factor analysis of FFQ data to identify dietary patterns among Yup'ik people

An FFQ developed by the Center for Alaska Native Health Research for studies in Yup'ik people includes market foods and subsistence foods such as moose, seal, waterfowl and salmon that may be related to disease risk. Because the FFQ contains >100 food items, we sought to characterize dietary patterns more simply for use in ongoing pharmacogenomics studies. Exploratory factor analysis was used to derive a small number of 'factors' that explain a substantial amount of the variation in the Yup'ik diet. We estimated factor scores and measured associations with demographic characteristics and biomarkers. South-west Alaska, USA. Yup'ik people (n 358) aged ≥18 years. We identified three factors that each accounted for ≥10 % of the common variance: the first characterized by 'processed foods' (e.g. salty snacks, sweetened cereals); the second by 'fruits and vegetables' (e.g. fresh citrus, potato salad); and the third by 'subsistence foods' (seal or walrus soup, non-oily fish). Participants from coastal communities had higher values for the 'subsistence' factor, whereas participants from inland communities had higher values for the 'fruits and vegetables' factor. A biomarker of marine intake, δ 15N, was correlated with the 'subsistence' factor, whereas a biomarker of corn- and sugarcane-based market food intake, δ 13C, was correlated with 'processed foods'. The exploratory factor analysis identified three factors that appeared to reflect dietary patterns among Yup'ik based on associations with participant characteristics and biomarkers. These factors will be useful for chronic disease studies in this population.

Water: The Gift of a Good Question

Ann Fienup-Riordan Ann Fienup-Riordan, Calista Elders Council, 9951 Prospect Dr., Anchorage AK 99507; riordan{at}alaska.net

The Center for Alaska Native Health Research Study: a community-based participatory research study of obesity and chronic disease-related protective and risk factors

Objectives. To describe the background, approach and general results of the Center for Alaska Native Health Research (CANHR) study.Study Design. This was a cross-sectional Community-Based Participatory Research (CBPR) study with one tribal group to assess risk and protection for obesity and the risk factors related to chronic disease, diabetes and cardiovascular disease.Methods. A combination of biological, genetic, nutritional and psychosocial measurements were taken on 922 Alaska Native participants in ten communities in Southwestern Alaska. The paper reports on data from 753 adult participants.Results. The prevalence of type 2 diabetes is 3.3% in the sample population. Metabolic syndrome is significantly lower among the males and equal for females when compared with Caucasians in the NHANES III sample. Obesity among adults is now at the national average. Risk factors for chronic disease include a shift to a Westernized diet, stress, obesity and impaired fasting glucose and protective factors include high levels of polyunsaturated fatty acid dietary intake. Articles in this issue present specific results in these areas.Conclusions. The data strongly indicate that, in general, Yup`ik people in our study are metabolically healthy and that diet and life style provide a delicate combination of protective and risk factors. The results strongly indicate that solution focused research utilizing primary and secondary prevention strategies may provide evidence for how to intervene to prevent further increases of chronic diseases. Research that focuses on relating the intrinsic strengths of indigenous worldviews and practices with basic research may contribute to positive transformations in community health. The Center for Alaska Native Health Research Study: a community-based participatory research study of obesity and chronic disease-related protective and risk factors. Mohatt GV, Plaetke R, Klejka J, Luick B, Lardon C, Bersamin A, Hopkins S, Dondanville M, Herron J, Boyer B ABSTRACT [full text] back to issue 66(1)] OBJECTIVES: To describe the background, approach and general results of the Center for Alaska Native Health Research (CANHR) study.Study Design. This was a cross-sectional Community-Based Participatory Research (CBPR) study with one tribal group to assess risk and protection for obesity and the risk factors related to chronic disease, diabetes and cardiovascular disease.Methods. A combination of biological, genetic, nutritional and psychosocial measurements were taken on 922 Alaska Native participants in ten communities in Southwestern Alaska. The paper reports on data from 753 adult participants.Results. The prevalence of type 2 diabetes is 3.3% in the sample population. Metabolic syndrome is significantly lower among the males and equal for females when compared with Caucasians in the NHANES III sample. Obesity among adults is now at the national average. Risk factors for chronic disease include a shift to a Westernized diet, stress, obesity and impaired fasting glucose and protective factors include high levels of polyunsaturated fatty acid dietary intake. Articles in this issue present specific results in these areas.Conclusions. The data strongly indicate that, in general, Yup`ik people in our study are metabolically healthy and that diet and life style provide a delicate combination of protective and risk factors. The results strongly indicate that solution focused research utilizing primary and secondary prevention strategies may provide evidence for how to intervene to prevent further increases of chronic diseases. Research that focuses on relating the intrinsic strengths of indigenous worldviews and practices with basic research may contribute to positive transformations in community health.

Stress, coping, and well-being among the Yup`ik of the Yukon-Kuskokwim Delta: the role of enculturation and acculturation

Objectives. To report on the relationships between cultural identity and stress, coping, and psychological well-being in Yup`ik communities.Study Design. A quantitative self-administered questionnaire.Methods. A health and wellness survey was completed by a total of 488 Yup`ik participants (284 women and 204 men) from 6 rural villages in the Yukon-Kuskokwim Delta region. Respondents were fairly equally distributed across an age range of 14 to 94 (mean +/- SD = 38.50 +/- 17.18).Results. Participants who reported living more of a Kass`aq way of life (greater acculturation) reported experiencing greater psychosocial stress, less happiness, and greater use of drugs and alcohol to cope with stress. Participants who reported identifying more with a traditional Yup`ik way of life reported greater happiness, more frequent use of religion and spirituality to cope with stress, and less frequent use of drugs and alcohol to cope with stress.Conclusions. In conjunction with previous research, the data strongly indicates that in general, Yup`ik people in the Y-K Delta tend to associate stress and negative health outcomes with the process of acculturation, and health and healing with the process of enculturation. Research that focuses on documenting the intrinsic strengths of indigenous worldviews may contribute to positive transformations in community health.

Wise words of the Yup'ik people: we talk to you because we love you

The people of southwestern Alaska were some of the last Arctic peoples to come into contact with non-Natives, and as a result, language and many traditions remain vital into the twenty-first century. Wise Words of the People documents their qanruyutet (adages, words of wisdom, and oral instructions) regarding the proper living of life. Throughout history, these distinctive wise words have guided the relations between men and women, parents and children, siblings and cousins, fellow villagers, visitors, strangers, and even with non-Natives. elders chose to share these wise words during Calista Elders Council gatherings and conventions since 1998 for instrumental reasons - because of their continued relevance and power to change lives.The Calista Elders Council, which represents some thirteen hundred elders, recently spearheaded efforts at cultural revitalization through gatherings with younger community members. In describing the content of traditional instruction as well as its central motivation - 'We talk to you because we love you' - elders not only educate young people, but also open a window into their view of the world for all of us. Wise Words of the People will serve as a valuable resource for the people and those who wish to learn more about their lives and values. Ann Fienup-Riordan is an independent scholar who has lived, worked, and taught in Alaska since 1973. Her many books include Hunting Tradition in a Changing World: Lives in Alaska Today and Yup'ik Elders at the Ethnologisches Museum Berlin: Fieldwork Turned on Its Head. Alice Rearden is a speaker and leading translator for the Calista Elders Council.

Academic and practical intelligence: A case study of the Yup'ik in Alaska

We assessed the importance of academic and practical intelligence in rural and relatively urban Yup'ik Alaskan communities with respect to Yup'ik-valued traits rated by adults or peers in the adolescents' communities. A total of 261 adolescents participated in the study; of these adolescents, 145 were females and 116 were males, and they were from seven different communities, six rural ( n=136) and one relatively urban ( n=125). We measured academic intelligence with conventional measures of fluid and crystallized intelligence. We measured practical intelligence with a test of everyday-life knowledge as acquired in Native Alaskan Yup'ik communities. Finally, we collected ratings from the adolescents' peers and adults on the traits that are valued by the Yup'ik people; thus, we evaluated the reputation for the Yup'ik-valued competences. The objective of the study was to estimate the relative contributions of conventional knowledge and everyday-life knowledge in predicting the ratings on Yup'ik-valued traits. The results indicated that everyday-life knowledge predicts Yup'ik-valued traits in the presented sample and that the predictive power of this knowledge is higher in adolescents (especially boys) from rural communities than from the semiurban community. The obtained result pattern further strengthens our arguments for the multidimensionality of human abilities and the importance of practical intelligence in nonacademic settings.

Incorporating Yup'ik and Cup'ik Eskimo Traditions Into Behavioral Health Treatment

The Yup'ik and Cup'ik Eskimo of Southwest Alaska have developed programs to provide healing from historical trauma. The Village Sobriety Project, a Center for Substance Abuse Treatment-funded project administered by the Yukon-Kuskokwim Health Corporation from 1999 to 2002, is an effort to incorporate the local Yup'ik and Cup'ik peoples' ways into treatment services for mental health and substance abuse. Activities such as tundra walks and time with elders are supported in treatment, and Medicaid reimbursement was successfully obtained for such activities. Documentation of treatment showed that it incorporated cultural elements of the Yup'ik and Cup'ik people.

Hunting tradition in a changing world: Yup'ik lives in Alaska today

The Yupiit in southwestern Alaska are members of the larger family of Inuit cultures. Including more than 20,000 individuals in seventy villages, the Yupiit continue to engage in traditional hunting activities, carefully following the seasonal shifts in the environment they know so well. During the twentieth century, especially after the construction of the trans-Alaska oil pipeline, the Yup'ik people witnessed and experienced explosive cultural changes. Anthropologist Ann Fienup-Riordan explores how these subarctic hunters engage in a hunt for history, to make connections within their own communities and between them and the larger world. She turns to the Yupiit themselves, joining her essays with eloquent narratives by individual Yupiit, which illuminate their hunting traditions in their own words. To highlight the ongoing process of cultural negotiation, Fienup-Riordan provides vivid examples: How the Yupiit use metaphor to teach both themselves and others about their past and present lives; how they maintain their cultural identity, even while moving away from native villages; and how they worked with museums in the Lower 48 on an exhibition of Yup'ik ceremonial masks. Ann Fienup-Riordan has published many books on Yup'ik history and oral tradition, including Eskimo Essays: Yup'ik Lives and How We See Them, The Living Tradition of Yup'ik Masks and Boundaries and Passages. She has lived with and written about the Yupiit for twenty-five years.

Morality and the Ik

Colin Turnbull's book The Mountain People has aroused much non-academic as well as much academic interest. The success of The Ik, Peter Brook's recent stage adaptation of the book, shows how widespread this interest is. The interest centres on Turnbull's anthropological descriptions of his life with the Ik people. The Ik society is one in which the weak, the old and the children are left to fend for themselves and die. Help proffered to the needy is frowned upon. Food is snatched from the mouths of the old, medicine stolen from the sick, and children left to feed and house themselves at about the age of three. Sexual codes no longer exist, cruelty is thought amusing, and the weak and dying are exploited. Turnbull believes that he has discovered a people without morality; a society that previously possessed a moral code, but which lost it.