Stable isotopes of carbon and nitrogen as markers of dietary variation among sociocultural subgroups of Inuit in Greenland

Increasing health inequality among Inuit in Greenland from 1993 to 2018: Different patterns for household assets, urbanization and a sociocultural index as indicators of social position

Income inequality affects population health and wellbeing negatively. In Greenland, health inequality has been shown to exist among social groups, regionally and according to urbanization, and between Inuit and migrants from Denmark. The purpose of the study was to compare the changes in health inequality from 1993 to 2018 according to three measures of social position, i.e. a socioeconomic measure (household assets), a measure of urbanization and a composite sociocultural index. We hypothesized that social inequality in health increased parallel to the increasing economic inequality in Greenland. The sample was based on four population health surveys conducted among the Inuit in Greenland in 1993, 2005-2010, 2014 and 2018. The total number of interviews was 9024 and the total number of individuals interviewed was 5829, as participants were invited to several surveys as part of a cohort. As statistical measure of social disparity we used the slope index of inequality (SII) adjusted for age and sex. Analyses were performed with daily smoking, suicidal thoughts and obesity as health outcomes. Daily smoking was most prevalent among participants with low social position whereas obesity was most prevalent among participants with high social position. With household assets as indicator of social position, the results showed high and increasing social inequality for both daily smoking and obesity. Social inequality for daily smoking increased over time also for urbanization and the sociocultural index. The hypothesis that social inequality increased over time was thus confirmed for daily smoking and obesity but not for suicidal thoughts. With the results from the present study there is solid evidence to guide prevention and health care towards social equality in health.

Social determinants of dietary patterns, food basket costs and expenditure on alcohol and tobacco amongst Greenland Inuit

OBJECTIVE

Dietary transition, obesity and risky use of alcohol and tobacco are challenges to public health among indigenous peoples. The aim of the article was to explore the role of social position in dietary patterns and expenditures on food and other commodities.

DESIGN

Countrywide population health survey.

SETTING

Greenland.

PARTICIPANTS

2436 Inuit aged 15+ years.

RESULTS

Less than half of the expenditures on commodities (43 %) were used to buy nutritious food, and the remaining to buy non-nutritious food (21 %), alcoholic beverages (18 %) and tobacco (18 %). Participants were classified according to five dietary patterns. The cost of a balanced diet and an unhealthy diet was similar, but the cost per 1000 kJ was higher and the energy consumption was lower for the balanced diet. Participants with low social position chose the unhealthy pattern more often than those with high social position (40 % v. 24 %; P < 0·0001), whereas those with high social position more often chose the balanced alternative. Participants with low social position spent less money on the total food basket than those with high social position but more on non-nutritious food, alcohol and tobacco.

CONCLUSIONS

Cost seems to be less important than other mechanisms in the shaping of social dietary patterns and the use of alcohol and tobacco among the Inuit in Greenland. Rather than increasing the price of non-nutritious food or subsidising nutritious food, socially targeted interventions and public health promotion regarding food choice and prevention of excessive alcohol use and smoking are needed to change the purchase patterns.

Hand grip strength and chair stand test amongst Greenlandic Inuit: reference values and international comparisons

Muscle strength is an important predictor for function and mortality among older adults. We measured hand grip strength among 1442 participants aged 15+ years and carried out a 30 second chair stand test among 786 participants aged 55+ years. Neither test has been carried out among the Inuit before. We present reference values for men and women as means with standard deviations and medians with 10^th, 25^th, 75^th and 90^th percentiles. Hand grip strength was higher among men than among women (means 45.2 kg and 25.8 kg; p < 0.0001), in linear regression analyses it increased with height (β_men = 0.69; β_women = 0.46), weight (β_men = 0.24; β_women = 0.08) and body mass index (β_men = 0.56; β_women = 0.24), and decreased with age (β_men = −0.49; β_women = −0.29) and Inuit genetic ancestry (β_men = −0.96; β_women = −0.59). Chair stand score showed similar associations with sex (mean score for men and women 13.8 and 11.5; p < 0.0001), age (β_men = −0.22; β_women = −0.20) and Inuit genetic ancestry (β_men = −0.38; β_women = −0.41). The hand grip strength of the Inuit was at the same level as in European and North American populations whereas chair stand score was lower than that of a mostly white US population.

Associations of plasma, RBCs, and hair carbon and nitrogen isotope ratios with fish, meat, and sugar-sweetened beverage intake in a 12-wk inpatient feeding study

BACKGROUND

Naturally occurring carbon and nitrogen stable isotope ratios [13C/12C (CIR) and 15N/14N (NIR)] are promising dietary biomarkers. As these candidate biomarkers have long tissue residence times, long-term feeding studies are needed for their evaluation.

OBJECTIVE

Our aim was to evaluate plasma, RBCs, and hair CIR and NIR as biomarkers of fish, meat, and sugar-sweetened beverage (SSB) intake in a 12-wk dietary intervention.

METHODS

Thirty-two men (aged 46.2 ± 10.5 y; BMI: 27.2 ± 4.0 kg/m2) underwent a 12-wk inpatient dietary intervention at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) in Phoenix, Arizona. The effects of fish, meat, and SSB intake on CIR and NIR were evaluated using a balanced factorial design, with each intake factor at 2 levels (present/absent) in a common, background diet (50% carbohydrate, 30% fat, 20% protein). Fasting blood samples were taken biweekly from baseline, and hair samples were collected at baseline and postintervention. Data were analyzed using multivariable regression.

RESULTS

The postintervention CIR of plasma was elevated when diets included meat (β = 0.89, 95% CI: 0.73,1.05) and SSBs (β = 0.48, 95% CI: 0.32, 0.64). The postintervention NIR of plasma was elevated when diets included fish (β = 0.85, 95% CI: 0.64, 1.05) and meat (β = 0.61, 95% CI: 0.42, 0.8). Results were similar for RBCs and hair. Postintervention RBC CIR and NIR had strong associations with baseline, suggesting that turnover to the intervention diets was incomplete after 12 wk. Estimates of isotopic turnover rate further confirmed incomplete turnover of RBCs.

CONCLUSIONS

CIR was associated with meat and SSBs, and more strongly with meat. NIR was associated with fish and meat, and more strongly with fish. Overall, CIR and NIR discriminated between dietary fish and meat, and to a lesser extent SSBs, indicating their potential utility as biomarkers of intake in US diets. Approaches to make these biomarkers more specific are needed. This trial was registered at clinicaltrials.gov as NCT01237093.

Measuring social inequality in health amongst indigenous peoples in the Arctic. A comparison of different indicators of social disparity among the Inuit in Greenland

The purpose of the article is to compare different indicators of social position as measures of social inequality in health in a population sample from an indigenous arctic people, the Inuit in Greenland. Data was collected during 2005-2015 and consisted of information from 3967 adult Inuit from towns and villages in all parts of Greenland. Social inequalities for smoking and central obesity were analysed in relation to seven indicators of social disparity in four dimensions, i.e. education and employment, economic status, sociocultural position, and place of residence. For each indicator we calculated age-adjusted prevalence by social group, rate ratio and the concentration index. The indicators were correlated with Pearson's r ranging from 0.24 to 0.82. Concentration indices ranged from 0.01 to 0.17. We could not conclude that one indicator was superior to others. Most of the indicators were traditional socioeconomic indicators used extensively in research in western countries and these seemed to be useful among the Inuit too, in particular household assets and job. Two sociocultural indicators developed for use among the Inuit and which included parameters specific to the indigenous peoples in the transition from a traditional to a modern life style proved to be equally useful but not superior to the traditional socioeconomic indicators. The choice of indicator must depend on what it is realistic to collect in the actual research setting and the use of more than one indicator is recommended. It is suggested to further develop culture specific indicators of social position for indigenous peoples.