title: Sun exposure and vitamin D status as Northeast Asian migrants become acculturated to life in Australia.
abstract: Vitamin D deficiency is more common in Northeast-Asian immigrants to western countries than in the local population; prevalence equalizes as immigrants adopt the host country's culture. In a community-based study of 100 Northeast-Asian immigrants in Canberra, Australia, we examined predictors of vitamin D status, its association with indicators of acculturation (English language use; time since migration) and mediators of that association. Participants completed a sun and physical activity diary and wore an electronic ultraviolet radiation (UVR) dosimeter for 7 days. Skin colour was measured by reflectance spectrophotometry. Serum concentrations of 25-hydroxyvitamin D (25(OH)D) and cardio-metabolic biomarkers were measured on fasting blood. In a multiple linear regression model, predictors for 25(OH)D concentration were season of blood collection, vitamin D supplementation, UVR exposure, body mass index, physical activity and having private health insurance (R(2) = 0.57). Greater acculturation was associated with lower risk of vitamin D deficiency (de-seasonalized 25(OH)D level <50 nmol L(-1)) (Adjusted Odds Ratio (AOR): 0.22 [95%CI 0.04-0.96]); this association was statistically mediated by physical activity and time outdoors. Vitamin D deficiency was associated with higher total cholesterol levels (>5.0 mmol L(-1)) (AOR: 7.48 [95%CI 1.51-37.0]). Targeted public health approaches are required to manage the high prevalence of vitamin D deficiency in migrants retaining a traditional lifestyle.
authors.affiliation: National Centre for Epidemiology and Population Health, Research School of Population Health, The Australian National University, Canberra, ACT, Australia.
authors.forename: Shuyu
authors.initials: S
authors.lastname: Guo
authors.forename: Peter
authors.initials: P
authors.lastname: Gies
authors.forename: Kerryn
authors.initials: K
authors.lastname: King
authors.forename: Robyn M
authors.initials: RM
authors.lastname: Lucas
mesh_terms: D000293:Adolescent; D000328:Adult; D001208:Asia / Q000208:ethnology; D001315:Australia; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013472:Sunlight; D014807:Vitamin D / Q000096:biosynthesis*
chemical_list: D014807:Vitamin D