Dietary habits, metabolic health and vitamin D status in Greenlandic children

Sociodemographic patterning of dietary profiles among Inuit youth and adults in Nunavik, Canada: a cross-sectional study

OBJECTIVES

Country (traditional) foods are integral to Inuit culture, but market food consumption is increasing. The Qanuilirpitaa? 2017 Nunavik Health Survey (Q2017) reported similar country food consumption frequency compared to that in 2004; however, examining food items individually does not account for diet patterns, food accessibility, and correlations between food items. Our objective was to identify underlying dietary profiles and compare them across sex, age, ecological region, and food insecurity markers, given the links among diet, health, and sociocultural determinants.

METHODS

Food frequency and sociodemographic data were derived from the Q2017 survey (N = 1176). Latent profile analysis identified dietary profiles using variables for the relative frequencies of country and market food consumption first, followed by an analysis with those for country food variables only. Multinomial logistic regression examined the associations among dietary profiles, sociodemographic factors, and food insecurity markers (to disassociate between food preferences and food access).

RESULTS

Four overall dietary profiles and four country food dietary profiles were identified characterized by the relative frequency of country and market food in the diet. The patterns were stable across several sensitivity analyses and in line with our Inuit partners' local knowledge. For the overall profiles, women and adults aged 30-49 years were more likely to have a market food-dominant profile, whereas men and individuals aged 16-29 and 50+ years more often consumed a country food-dominant profile. In the country food profiles, Inuit aged 16-29 years were more likely to have a moderate country food profile whereas Inuit aged 50+ were more likely to have a high country food-consumption profile. A low country and market food-consumption profile was linked to higher prevalence of food insecurity markers.

CONCLUSION

We were able to identify distinct dietary profiles with strong social patterning. The profiles elucidated in this study are aligned with the impact of colonial influence on diet and subsequent country food promotion programs for Inuit youth. These profiles will be used for further study of nutritional status, contaminant exposure, and health to provide context for future public health programs.

High Prevalence of Hypovitaminosis D in Adolescents Attending a Reference Centre for the Treatment of Obesity in Switzerland

Background: Hypovitaminosis D is common in populations with obesity. This study aimed at assessing (1) the prevalence of hypovitaminosis D and (2) the associations between vitamin D levels and cardiovascular risk factors in adolescents attending a reference centre for the treatment of obesity. Design: Cross-sectional pilot study conducted in the paediatric obesity unit of the Lausanne university hospital, Switzerland. Methods: Participants were considered eligible if they (1) were aged between 10 to 16.9 years and (2) consulted between 2017 and 2021. Participants were excluded if (1) they lacked vitamin D measurements or (2) the vitamin D measurement was performed one month after the base anthropometric assessment. Hypovitaminosis D was considered if the vitamin D level was <30 ng/mL (<75 nmol/L). Severe obesity was defined as a BMI z-score > 3 SD. Results: We included 52 adolescents (31% girls, mean age 13 ± 2 years, 33% with severe obesity). The prevalence of hypovitaminosis D was 87.5% in girls and 88.9% in boys. The vitamin D levels were inversely associated with BMI, Spearman r and 95% CI: −0.286 (−0.555; −0.017), p = 0.037; they were not associated with the BMI z-score: −0.052 (−0.327; 0.224), p = 0.713. The vitamin D levels were negatively associated with the parathormone levels (−0.353 (−0.667; −0.039), p = 0.028) and positively associated with the calcium levels (0.385 (0.061; 0.708), p = 0.020), while no association was found between vitamin D levels and blood pressure and lipid or glucose levels. Conclusion: almost 9 out of 10 adolescents with obesity in our cohort presented with hypovitaminosis D. Hypovitaminosis D does not seem to be associated with a higher cardiovascular risk profile in this group.

Inuit Country Food and Health during Pregnancy and Early Childhood in the Circumpolar North: A Scoping Review

Inuit communities in the Circumpolar North have experienced a nutrition transition characterized by the decreased intake of culturally important, nutrient-rich traditional food (country food), and an increased intake of market food, resulting in concerns over reduced diet quality and emerging chronic diseases. Nutrition in early life is critical for development, may influence health risks in later life, and is an important concern for Inuit community health. The goal of this scoping review was to characterize the nature, extent, and range of the published literature on Inuit country food and health in pregnancy and childhood. A search string was developed and applied to three databases, followed by title and abstract screening and full text review. Articles published between 1995 and 2019 were included, and data were extracted and summarized descriptively. The number of articles generally increased over time, despite the unequal geographic distribution of articles. The majority of the articles focused on environmental contaminants, and one-quarter described nutrient adequacy. Few articles described food security or food safety in pregnancy, and the most utilized quantitative methods. Gaps in understanding of country food use in pregnancy and early childhood highlight areas of future research to support public health policy for this population. Given the critical role of good nutrition in early life and the important contribution country food makes to diet quality for Inuit, further understanding of this interface is warranted.

Adaptation and co-adaptation of skin pigmentation and vitamin D genes in native Americans

We carried out an exhaustive review regarding human skin color variation and how much it may be related to vitamin D metabolism and other photosensitive molecules. We discuss evolutionary contexts that modulate this variability and hypotheses postulated to explain them; for example, a small amount of melanin in the skin facilitates vitamin D production, making it advantageous to have fair skin in an environment with little radiation incidence. In contrast, more melanin protects folate from degradation in an environment with a high incidence of radiation. Some Native American populations have a skin color at odds with what would be expected for the amount of radiation in the environment in which they live, a finding challenging the so-called "vitamin D-folate hypothesis." Since food is also a source of vitamin D, dietary habits should also be considered. Here we argue that a gene network approach provides tools to explain this phenomenon since it indicates potential alleles co-evolving in a compensatory way. We identified alleles of the vitamin D metabolism and pigmentation pathways segregated together, but in different proportions, in agriculturalists and hunter-gatherers. Finally, we highlight how an evolutionary approach can be useful to understand current topics of medical interest.