Search

Through their marine-based diet, the Inuit of Nunavik (Quebec) are exposed to neurotoxic environmental contaminants that impact cognitive development. Mercury levels in Nunavik Inuit mothers and newborns were higher than in U.S. and Canadian populations but lower than in previous Arctic samples. Lead, polychlorinated biphenyls, chorinated pesticides, and possibly protective substances (selenium and N-3 polyunsaturated fatty acids) were also measured. (SV)

The article discusses a study which aimed to determine whether higher dairy product intake will have beneficial effects on body weight and cardiovascular disease (CVD) risk factors among a population in dietary transition, the Nunavik Inuit in Canada. The researchers found no substantial relationship and concluded that the daily consumption of dairy products is probably not adequate, as experienced in North American populations.

Epidemiological studies report inverse associations between blood vitamin D, as measured by 25-hydroxyvitamin D [25(OH)D] concentrations, and insulin resistance (IR) among predominantly overweight individuals. In a cross-sectional survey of 5 Cree communities in Quebec, Canada, we determined if 25(OH)D is associated with IR and β-cell function in a largely obese, ethnic minority at high risk of developing type 2 diabetes. A total of 510 participants (=18 y) without type 1 or type 2 diabetes, assessed for serum 25(OH)D, fasting plasma glucose and insulin, and anthropometric and lifestyle variables, were included in the analyses. Multivariable linear regressions adjusted for covariates were performed for homeostasis model assessment of IR (HOMA-IR) and β-cell function (HOMA-B) in relation to serum 25(OH)D. Serum 25(OH)D (per 10 nmol/L increment) was inversely associated with HOMA-IR (β = -0.005; SE = 0.002; P = 0.004) and HOMA-B (β = -0.004; SE = 0.002; P = 0.006) in models adjusted for age, sex, physical activity, education, alcohol consumption, and smoking. When further adjusted for BMI, associations were no longer significant for either HOMA-IR (β = 0.001, SE = 0.002, P = 0.572) or HOMA-B (β = 0.001, SE = 0.001, P = 0.498). The modest inverse associations between 25(OH)D and IR reported previously were not observed in this population after adjusting for adiposity. Future longitudinal studies investigating the interrelationship among 25(OH)D, adiposity, and the risk of developing metabolic syndrome and type 2 diabetes are warranted. [ABSTRACT FROM AUTHOR]

Background: Inuit women from Northern Quebec have been shown to consume inadequate quantities of vitamin A. This study was conducted to evaluate the prevalence of blood vitamin A deficiency in newborns from 3 distinct populations of the province of Quebec. Methods: 594 newborns were included in this study (375 Inuit newborns from northern Québec (Nunavik), 107 Caucasian and Native newborns from the Lower Northern Shore of the Saint-Lawrence River (LNS) and 112 newborns from Southern Quebec where clinical vitamin A deficiency is uncommon). Mothers were recruited at delivery and vitamin A (retinol) was analyzed from umbilical cord blood samples by reversed-phase high-pressure liquid chromatography. Results: Nunavik and LNS newborns had significantly lower mean vitamin A concentrations in cord blood compared to Southern Québec participants (15.7 µg/dL, 16.8 µg/dL and 20.4 µg/dL respectively). The differences observed were similar when adjusted for sex and birthweight. Results also showed that 8.5% of Nunavik newborns and 12.2% of INS newborns were below 10.0 µg/dL, a level thought to be indicative of blood vitamin A deficiency in neonates. Conclusion: These data suggest that a carefully planned vitamin A supplementation program during pregnancy in Nunavik and LNS might be indicated to promote healthy infant development. [ABSTRACT FROM AUTHOR]

In an exploratory study, levels of cadmium in whole-kidney and liver tissues of 314 subjects from the general population of the province of Quebec (Canada) were measured postmortem. Frequency distributions of cadmium concentrations were lognormal. As reported in similar studies, age and especially smoking habits were the main variables affecting cadmium concentrations. The geometric mean of whole kidney concentrations (wet weight) was 17.62 mug/g, with a minimum concentration of 2.25 mug/g and a maximum of 100.61 mug/g. Mean concentrations of cadmium in kidneys increased with age, reaching a plateau in the group 50 to 59 yr (29.49 mug/g), and falling slowly thereafter. [ABSTRACT FROM AUTHOR]

We evaluated alveolar carbon monoxide (CO) levels of 122 male, adult hockey players active in recreational leagues of the Quebec City region (Canada), before and after 10 weekly 90-minute games in 10 different rinks. We also determined exposure by quantifying the average CO level in the rink during the games. Other variables documented included age, pulmonary function, aerobic capacity, and smoking status. Environmental concentrations varied from 1.6 to 131.5 parts per million (ppm). We examined the absorption/exposure relationship using a simple linear regression model. In low CO exposure levels, physical exercise lowered the alveolar CO concentration. However, we noted that for each 10 ppm of CO in the ambient air, the players had adsorbed enough CO to raise their carboxyhemoglogin (COHb) levels by 1 percent. This relationship was true both for smokers and non-smokers. We suggest that an average environmental concentration of 20 ppm of CO for the duration of a hockey game (90 minutes) should be the reference limit not to be exceeded in indoor skating rinks. (Am J Public Health 1990; 80: 594-598.) [ABSTRACT FROM AUTHOR]

Evaluates blood levels of lead, mercury and organochlorine compounds in newborns in the province of Quebec. Proportion of newborns at risk of developing neurobehavioral problems; Results of the study; Discussion of the results.

While policies to decrease lead in the environment have been implemented to reduce human exposure to various lead sources, the use of lead ammunition to harvest wild game may continue to contribute significantly to human blood lead levels (BLLs). As part of a multi-community environment-and-health study, BLLs representing all age groups were evaluated in the nine Cree Nations located in the James and Hudson Bay regions of Quebec, Canada. Personal, market food, traditional food and 24-h recall questionnaires were administered. Predictor variables were assessed for various exposure sources, including diet and hunting practices. Elevated BLLs were observed in association with increased hunting status, use of firearms and leaded ammunition, and consumption of traditional foods. Significant differences were observed between all communities, age groups and sexes. Recommendations include educational campaigns that promote switching to non-lead ammunition and, if lead ammunition continues to be used, careful removal from tissues of pellets, bullet fragments and ammunition paths., (Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.)

Background: Inuit are considered to be vulnerable to cardiovascular disease because their lifestyles are becoming more Westernized. During sequence analysis of Inuit individuals at extremes of lipid traits, we identified 2 nonsynonymous variants in low-density lipoprotein receptor (LDLR), namely p.G116S and p.R730W., Methods and Results: Genotyping these variants in 3324 Inuit from Alaska, Canada, and Greenland showed they were common, with allele frequencies 10% to 15%. Only p.G116S was associated with dyslipidemia: the increase in LDL cholesterol was 0.54 mmol/L (20.9 mg/dL) per allele (P=5.6×10(-49)), which was >3× larger than the largest effect sizes seen with other common variants in other populations. Carriers of p.G116S had a 3.02-fold increased risk of hypercholesterolemia (95% confidence interval, 2.34-3.90; P=1.7×10(-17)), but did not have classical familial hypercholesterolemia. In vitro, p.G116S showed 60% reduced ligand-binding activity compared with wild-type receptor. In contrast, p.R730W was associated with neither LDL cholesterol level nor altered in vitro activity., Conclusions: LDLR p.G116S is thus unique: a common dysfunctional variant in Inuit whose large effect on LDL cholesterol may have public health implications., (© 2014 American Heart Association, Inc.)

Our cross-sectional study assessed the associations between dietary patterns and cardiovascular disease (CVD) risk factors among Nunavik Inuit. This study was conducted as part of the 2004 Nunavik Inuit Health Survey, which included the collection of clinical measurements, plasma samples, and diet information from a food frequency questionnaire. A sample of 666 Inuit aged 18 years and older was included in our analyses. Dietary patterns were generated by principal component analysis. Multivariate general linear models adjusting for sex, age, waist circumference, and other potential confounders were used to examine associations between dietary patterns and CVD risk factors. Four distinct patterns were identified, namely the traditional, Western, nutrient-poor food, and healthy patterns. The traditional pattern showed positive associations with plasma total cholesterol, low-density lipoprotein (LDL) cholesterol, apolipoprotein B100, LDL peak particle diameter, and oxidized LDL (all P values for trend≤0.04), but showed no association with the total cholesterol:high-density lipoprotein cholesterol ratio or with inflammatory biomarkers (all P values for trend ≥0.19). The nutrient-poor food pattern was positively associated with oxidized LDL (P=0.04), but inversely associated with high-sensitivity C-reactive protein (P<0.0001). The Western and healthy patterns showed no association with any CVD risk factor. Our data show that high adherence to a traditional pattern among Nunavik Inuit is not associated with important changes in CVD risk factors, with the exception of a slight elevation in cholesterol concentrations, most likely attributable to increased n-3 fatty acid intake. Dietary patterns reflecting the recent introduction of market foods in the Inuit diet appear to exert a trivial influence on CVD risk factors., (Copyright © 2014 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.)

Objectives: Inuit in Canada experience alarming levels of food insecurity, but nutritional and physiological consequences are poorly documented, especially in school-age children. The objective of this study was to assess the relation of food insecurity to iron deficiency and stature in school-aged Inuit children from Nunavik (Northern Quebec)., Methods: Food insecurity, iron deficiency, and stature were assessed in a cohort of children. Food insecurity was determined by interviewing the children's mothers. Multiple logistic regression was used to evaluate the association of food insecurity to iron deficiency and short stature. We defined short stature as a height in the lowest tertile for age and sex, based on Canadian growth charts. The relation of food insecurity to height (cm) was analyzed with a general linear model. Statistical models controlled for age, sex, normal/overweight/obese status, prenatal lead exposure and postnatal polychlorinated biphenyls exposure., Results: Half of the children (49.7%, n=145) were food insecure, while one third were iron depleted, 12.6% had anaemia, and 8.7% had iron-deficiency anaemia. The multivariate odds ratio of anaemia was 1.82 (95% CI: 0.97, 3.42, p=0.06) for food-insecure children. Prevalence of short stature was 18.7%. Food-insecure children were an average of 2 cm shorter (95% CI: -0.48, -3.17) than food-secure children (p<0.01)., Conclusion: In this population, food-insecure children have greater burdens of nutritional deficiencies and slower linear growth. Considering the high prevalence of food insecurity among Inuit children in Nunavik, nutritional deficiencies and adverse effects on development should be carefully monitored.

Background: Household crowding is an important problem in some aboriginal communities that is reaching particularly high levels among the circumpolar Inuit. Living in overcrowded conditions may endanger health via stress pathophysiology. This study examines whether higher household crowding is associated with stress-related physiological dysregulations among the Inuit., Methods: Cross-sectional data on 822 Inuit adults were taken from the 2004 Qanuippitaa? How are we? Nunavik Inuit Health Survey. Chronic stress was measured using the concept of allostatic load (AL) representing the multisystemic biological 'wear and tear' of chronic stress. A summary index of AL was constructed using 14 physiological indicators compiled into a traditional count-based index and a binary variable that contrasted people at risk on at least seven physiological indicators. Household crowding was measured using indicators of household size (total number of people and number of children per house) and overcrowding defined as more than one person per room. Data were analysed using weighted Generalised Estimating Equations controlling for participants' age, sex, income, diet and involvement in traditional activities., Results: Higher household crowding was significantly associated with elevated AL levels and with greater odds of being at risk on at least seven physiological indicators, especially among women and independently of individuals' characteristics., Conclusions: This study demonstrates that household crowding is a source of chronic stress among the Inuit of Nunavik. Differential housing conditions are shown to be a marker of health inequalities among this population. Housing conditions are a critical public health issue in many aboriginal communities that must be investigated further to inform healthy and sustainable housing strategies.

Background: The Maternal-Infant Research on Environmental Chemicals (MIREC) Study was established to obtain Canadian biomonitoring data for pregnant women and their infants, and to examine potential adverse health effects of prenatal exposure to priority environmental chemicals on pregnancy and infant health., Methods: Women were recruited during the first trimester from 10 sites across Canada and were followed through delivery. Questionnaires were administered during pregnancy and post-delivery to collect information on demographics, occupation, life style, medical history, environmental exposures and diet. Information on the pregnancy and the infant was abstracted from medical charts. Maternal blood, urine, hair and breast milk, as well as cord blood and infant meconium, were collected and analysed for an extensive list of environmental biomarkers and nutrients. Additional biospecimens were stored in the study's Biobank. The MIREC Research Platform encompasses the main cohort study, the Biobank and follow-up studies., Results: Of the 8716 women approached at early prenatal clinics, 5108 were eligible and 2001 agreed to participate (39%). MIREC participants tended to smoke less (5.9% vs. 10.5%), be older (mean 32.2 vs. 29.4 years) and have a higher education (62.3% vs. 35.1% with a university degree) than women giving birth in Canada., Conclusions: The MIREC Study, while smaller in number of participants than several of the international cohort studies, has one of the most comprehensive datasets on prenatal exposure to multiple environmental chemicals. The biomonitoring data and biological specimen bank will make this research platform a significant resource for examining potential adverse health effects of prenatal exposure to environmental chemicals., (© 2013 John Wiley & Sons Ltd and Her Majesty the Queen in Right of Canada. Reproduced with the permission of the Minister of Health.)

Background: Studies conducted in the Faeroe Islands and Japan suggest a negative impact of mercury on heart rate variability (HRV) among children while the results regarding blood pressure (BP) are less consistent., Objective: To assess the impact of mercury on HRV and BP among Nunavik Inuit children., Methods: A cohort of 226 children was followed from birth to 11 years old. Mercury concentration in cord blood and in blood and hair at 11 years old were used as markers of prenatal and childhood exposure, respectively. HRV was measured using ambulatory 2 h-Holter monitoring while BP was measured through a standardized protocol. Simple regression was used to assess the relationship of mercury to BP and HRV parameters. Multiple linear regressions were performed adjusting for covariates such as age, sex, birth weight, body mass index (BMI), height, total n-3 fatty acids, polychlorinated biphenyls (PCB 153), lead, selenium and maternal smoking during pregnancy., Results: Median cord blood mercury and blood mercury levels at 11 years old were 81.5 nmoL/L (IQR:45.0–140.0) and 14.5 nmol/L (IQR: 7.5–28.0), respectively. After adjusting for the covariates, child blood mercury was associated with low frequency (LF) (b = 0.21, p = 0.05), the standard deviation of R–R intervals (SDNN) (b = 0.26, p = 0.02), the standard deviation of R–R intervals measured over 5 min periods (SDANN) (b = 0.31, p = 0.01) and the coefficient of variation of R–R intervals (CVRR) (b = 0.06,p = 0.02). No significant association was observed with BP., Conclusion: Mercury exposure during childhood seems to affect HRV among Nunavik Inuit children at school age.

Background: Omega-3 polyunsaturated fatty acids (n-3 PUFAs) may protect against dementia, although epidemiologic studies have yielded inconclusive results. Fish is the main dietary source of n-3 PUFAs and is sometimes contaminated with mercury. This neurotoxicant may modify the association with dementia., Objective: We evaluated the association of erythrocyte membrane total n-3 PUFAs, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and blood mercury with the incidence of dementia and Alzheimer disease (AD) in the Canadian Study of Health and Aging (CSHA) with adjustment for confounders including apolipoprotein E epsilon4 (APOE epsilon4) status., Design: The CSHA is a cohort study of a representative sample of persons aged > or =65 y, conducted from 1991 to 2002. A subsample of 663 nondemented CSHA subjects with a complete clinical examination, blood samples, and follow-up information was eligible for prospective analyses on laboratory measurements. Of these, 149 were incident cases of dementia, including 105 with AD., Results: In adjusted Cox regression models with age as the time scale, there were no associations between total n-3 PUFAs, DHA, or EPA and dementia or AD. In contrast, a mercury concentration in the highest quartile was associated with a reduced risk of dementia (hazard ratio: 0.53; 95% CI: 0.33, 0.88). However, significant risk reductions were limited to subjects with concentrations of both n-3 PUFAs and mercury that were above the median. There was no modification of risk by APOE epsilon4 status., Conclusions: No associations between n-3 PUFAs and dementia or AD were found. The results regarding mercury may indicate a spurious association.

Marine omega-3 (n-3) fatty acid eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids have been associated with beneficial effects in mental health. Cultural and social changes have been related to a decline in mental health of the Inuit, but the role of diet has received scant attention. We examined the relationship between psychological distress (PD) and plasma n-3 among 368 Nunavik Inuit aged 18-74 years who took part in a survey in 1992. Participants were categorized as high-level PD if they scored over the 80th percentile of the PD Index Santé-Québec Survey (PDISQS-14), and non-distressed subjects were those who scored less than this cutoff. Compared with the non-distressed group, n-3 concentrations in the PD group were significantly lower in women but not in men. Compared with the lowest tertile of EPA + DHA, the odds ratios for high-level PD among women were 0.32 (95% CI: 0.13-0.82) for the second, and 0.30 (95% CI: 0.10-0.90) for the third tertile, after controlling for confounders. In males, there were no significant associations between EPA+DHA and PDISQS-14 scores. Our findings suggest that marine n-3 may play a role in PD among Inuit women. The gender difference observed in our analysis must be examined more carefully in future studies.

Vitamin D has been associated with reduced breast cancer risk. We studied the association of two vitamin D receptor (VDR) gene single nucleotide polymorphisms restriction enzyme detecting SNP of VDR (FokI and BsmI) with breast cancer risk in two independent case-control studies carried out in the same population. The modifying effect of family history of breast cancer on this relationship was also evaluated. The first and second studies included respectively 718 (255 cases/463 controls) and 1596 (622 cases/974 controls) women recruited in Quebec City, Canada. FokI and BsmI genotypes were assessed. Relative risks of breast cancer were estimated by multivariate logistic regression. Compared with homozygotes for the common F allele (FF genotype), FokI ff homozygotes had a higher breast cancer risk (study 1: odds ratio (OR)=1.22, 95% confidence interval (CI)=0.76-1.95; study 2: OR=1.44, 95% CI=1.05-1.99; and combined studies: OR=1.33, 95% CI=1.03-1.73). Significant interactions were observed between FokI and family history of breast cancer in the two studies as well as in the combined analysis (P interaction=0.031, 0.050 and 0.0059 respectively). Among women without family history, odds ratios were 1.00, 1.27 (95% CI=1.02-1.58) and 1.57 (95% CI=1.18-2.10) respectively for FF, Ff and ff carriers (P(trend)=0.0013). BsmI Bb+bb genotypes were associated with a weak non-significant increased risk in the two studies (combined OR=1.22, 95% CI=0.95-1.57) without interaction with family history. Results support the idea that vitamin D, through its signalling pathway, can affect breast cancer risk. They also suggest that variability in observed associations between VDR FokI and breast cancer from different studies may partly be explained by the proportion of study subjects with a family history of breast cancer.

The Inuit are heavily exposed to potentially prooxidant contaminants such as methylmercury (MeHg) and polychlorinated biphenyls (PCB) through their traditional diet. This diet is also an abundant source of n-3 polyunsaturated fatty acids (n-3 PUFA), selenium, and antioxidants, which might reduce cardiovascular risk. Although Inuit from Nunavik have low concentrations of plasma oxidized low-density lipoprotein (OxLDL) and elevated glutathione-related antioxidant defenses, the variance in OxLDL was predicted by PCB and blood glutathione, leaving the issue of contaminant-associated oxidative stress unresolved. The objective of the study was to assess oxidative stress in these Inuit by measuring the plasma concentrations and redox states of alpha-tocopherol and coenzyme Q10 (CoQ10), 2 sensitive biomarkers of oxidative stress, in relation to exposure. Plasma lipophilic antioxidants were determined by high-performance liquid chromatography-coupled electrochemical detection; and their relations to PCB, MeHg, n-3 PUFA, selenium, and OxLDL were assessed by multivariate analyses. Ubiquinol-10, ubiquinone-10, and ubiquinone-10 to CoQ10(total) ratio were elevated as compared with white populations but showed no associations with PCB, MeHg, or n-3 PUFA. Ubiquinol-10 (beta = .23, P = .007) and CoQ10(total) (beta = .27, P = .009) were predicted by blood selenium; and alpha-tocopherol, by PCB (beta = 4.12, P = .0002), n-3 PUFA (beta = 9.16, P = .02), and OxLDL (beta = 3.04, P = .05). Unexpectedly, the alpha-tocopheryl quinone to alpha-tocopherol ratio, in the reference range, was negatively predicted by PCB (beta = -0.41, P = .02). Using sensitive biomarkers of redox alterations, we found no evidence for MeHg- or PCB-associated oxidative stress in these Inuit. However, despite robust blood antioxidant defenses, the unusually elevated ubiquinone-10 to CoQ10(total) ratio (0.21 +/- 0.11) suggests some form of oxidative stress of unknown origin.

Objectives: We investigated the prevalence of obesity and the metabolic correlates of different levels of body mass index (BMI) and waist circumference among the Inuit in 3 countries., Methods: Data from 4 surveys of Inuit in Canada, Greenland, and Alaska conducted during 1990-2001 were pooled, with a total sample size of 2545 participants. These data were compared with data from a Canadian population of predominantly European origin., Results: Using the World Health Organization criteria for overweight and obesity, we found that the crude prevalence of overweight among Inuit men and women was 36.6% and 32.5%, respectively, and obesity was 15.8% and 25.5%, respectively. Inuit prevalences were similar to those of the highly developed countries of Europe and North America. As levels of obesity increased, as measured by BMI or waist circumference, the mean values of various metabolic indicators-lipid, glucose, and insulin levels and blood pressure-also increased. However, at each level of BMI or waist circumference, the Inuit had lower blood pressure and lipid levels than did Euro-Canadians., Conclusions: Our data indicate that universal criteria for obesity may not reflect the same degree of metabolic risk for populations such as the Inuit and suggest that ethnic-specific criteria are needed.

The aim of the present study was to investigate the potential deleterious effects of dietary contaminants such as polychlorinated biphenyls (PCBs) and methylmercury (MeHg) on different molecules sensitive to oxidative stress, namely, plasma oxidized low-density lipoproteins (OxLDLs), plasma homocysteine (Hcy), blood glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione (GSH). We also planned to assess the potential beneficial effects of long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) and selenium (Se) that are also present in the traditional Inuit diet. A total of 99 participants were studied. Plasma levels of PCBs, blood levels of Se and MeHg, plasma lipids (triacylglycerols, total, LDL-, and high-density lipoprotein cholesterol [LDL-C and HDL-C, respectively], apolipoprotein B-LDL), erythrocyte n-3 PUFAs, OxLDL, Hcy, blood GPx, GSH, and GR have been determined. Mean concentrations of MeHg, Se, and PCBs were respectively 10- to 14-fold, 8- to 15-fold, and 16- to 18-fold higher than reported in white population consuming little or no fish. Multivariate analyses show that variance in plasma OxLDL concentrations was predicted by LDL-C (P = .007), HDL-C (P = .005), and PCBs (P = .006). The level of LDL oxidation, represented as the ratio OxLDL/apolipoprotein B-LDL, was predicted by LDL-C (P = .0002), HDL-C (P = .002), and GSH (P = .005). Concentration of plasma Hcy was positively predicted by age (P = .02) but negatively by body mass index (P = .04) and Se (P = .005). Glutathione was predicted by the smoking status (P = .004) and the level of LDL oxidation (P = .005), whereas GR was only predicted by the smoking status (P = .0009). The variance of GPx was not predicted by any contaminant or other physiological parameter. Dietary MeHg showed no association with the examined oxidative biomarkers, whereas PCB level was a predictor of the plasma concentration of OxLDL, although this concentration remained very low. The level of GPx activity in Inuit was higher than levels previously reported to be protective in whites. Homocysteine was negatively predicted by Se, suggesting a possible beneficial effect of Se. Moreover, n-3 PUFAs were highly correlated with dietary contaminants, but had no relationships with oxidative biomarkers. This study suggests that, in adult Inuit, contaminated traditional diet seems to have no direct oxidative effects on molecules involved in oxidative stress.

Objectives: We compared serum phospholipid fatty acid compositions, in particular the status of omega-3 polyunsaturated fatty acid (PUFA), of postmenopausal Greenland Inuit women and postmenopausal Canadian women at baseline and after supplementing the Canadian women with a fish-oil product., Methods: Fasting serum samples were collected from 15 Inuit subjects from Greenland and 16 non-Inuit subjects from Canada. In addition, eight Canadian subjects provided fasting serum samples after completing a long-chain omega-3 PUFA intervention (2.4 g of eicosapentaenoic acid [EPA] plus 1.6 g of docosahexaenoic acid [DHA] per day) for 28 d. Fatty acid compositions of serum phospholipids of the samples were determined and compared by one-way analysis of variance., Results: In comparison with the Greenlanders, baseline Canadian women had 73% and 46% less EPA (20:5omega-3) and DHA (22:6omega-3), respectively, and 32% and 91% more linoleic acid (LA; 18:2omega-6) and arachidonic acid (AA; 20:4omega-6), respectively. The omega-3 supplementation in Canadian women increased DHA and decreased LA levels to approach those in Greenland Inuit and raised EPA levels to surpass (45% higher) those in Greenland women (P < 0.0001). In contrast, AA was only moderately lowered (by 16% overall) such that AA levels remained 62% higher in the supplemented Canadians than in the Greenlanders (P < 0.0001)., Conclusions: Short-term EPA plus DHA supplementation of postmenopausal North American women can mimic the high EPA and DHA levels and lower LA levels in corresponding Inuit women but not the markedly lower levels of AA. The present findings also support the hypothesis of genetically decreased Delta5-desaturase potential in the Greenland Inuit compared with Canadian postmenopausal women.