Wild foods as drivers of blood ergothioneine and selenoneine concentrations among Inuit living in Nunavik: results from the cross-sectional Qanuilirpitaa? 2017 survey

BACKGROUND: Wild foods traditionally harvested by Inuit, also called country foods, are potential sources of ergothioneine and selenoneine, 2 closely related antioxidants with potential health benefits. OBJECTIVE: To determine concentrations of these compounds and methylated metabolites in blood samples from 1291 Nunavik residents (Nunavimmiut) aged ≥16 y who participated in the cross-sectional Qanuilirpitaa? 2017 Health Survey and associated dietary habits. METHODS: Blood levels were measured using isotope dilution-liquid chromatography-tandem MS. Associations with dietary profiles or selected dietary habits (documented by a food frequency questionnaire) were investigated using multivariate models. RESULTS: Geometric mean concentrations (95% confidence interval [CI]) of ergothioneine, S-methyl-ergothioneine, selenoneine, and Se-methyl-selenoneine, were 92.5 mg/L (88.4, 96.8), 139 μg/L (133, 146), 355 μg/L (328, 385) and 11.6 μg/L (10.7, 12.5), respectively. Geometric mean ratios (GMR) (95% CI) comparing females with males were 1.27 (1.18, 1.39) and 1.82 (1.57, 2.11) for ergothioneine and selenoneine, respectively. GMR comparing ≥60 y olds to youth aged 16 to 19 y were 1.75 (1.52, 2.02) and 2.78 (2.04, 3.69) for ergothioneine and selenoneine, respectively. Blood selenoneine concentrations of Hudson Strait residents exceeded those of Ungava Bay (2.38 [1.97, 2.86]) and Hudson Bay residents (2.70 [2.22, 3.28]). GMR comparing the high-country food consumption profile with none (or very low) profile were 1.33 (1.10, 1.61) and 2.35 (1.65, 3.36) for ergothioneine and selenoneine, respectively. Country foods positively associated with ergothioneine concentrations included Arctic char (1.07 [1.04, 1.10]) and caribou meat (1.06 [1.03, 1.10]), whereas country foods positively linked to selenoneine concentrations comprised Arctic char (1.07 [1.02, 1.12]) and beluga mattaaq (1.15 [1.08, 1.22]). CONCLUSIONS: Although comparative data are limited, blood selenoneine and ergothioneine concentrations among Nunavimmiut appear substantially higher than in other non-Indigenous populations. Access to country food is important to maintain the dietary intake of these bioactive food components that may be beneficial for the health of Nunavimmiut.