Prevalence of Inadequate Vitamin D Intake and Status, and Determining Factors for Serum Vitamin D Deficiency

Abstract

ObjectivesTo estimate the prevalence of inadequate vitamin D intake and status among residents in the urban area of Sao Paulo municipality, Brazil, and to verify the factors associated with this status.MethodsData from 288 individuals ≥19 years old were obtained from the cross-sectional study 2015 Health Survey of Sao Paulo with a focus on Nutrition (ISA-Nutrition), a cross-sectional study. Serum vitamin D levels (25(OH)D3) were assessed by chemiluminescent immunoassay (Diasorin kit, Stillwater, MN, USA). Dietary intake including supplements use was measured using two 24-h dietary recalls. The prevalence of inadequate intake was estimated according to National Center Institute method. The receiver operating characteristic curve was estimated to assess the intake information performance on serum status. Associations between serum vitamin D status and sociodemographic and lifestyle factors were analyzed using logistic regression.ResultsThere was observed a high prevalence of inadequate dietary vitamin D intake in the population (male: 87.5–99.4%; female: 92.4–99.8%). Women were more susceptible to deficient serum status than men (male: 59.4–89.0%; female: 83.0–93.8%), and higher prevalence of vitamin D deficiency occurred during the winter (male: 86.9–100.0%; female: 91.4–100.0%). Vitamin D intake had inefficient performance in correctly identifying individuals with serum deficiency (area under curve < 0.50), except among individuals 19–30 years old. Individuals with sufficient leisure physical activity had 57% lower risk to have serum vitamin D deficiency (p = 0.032).ConclusionsThere was a high prevalence of inadequate status and intake of vitamin D among residents of Sao Paulo, Brazil. Findings indicate that the dietary intake was not a good parameter to assess the serum vitamin D status, and the practice of sufficient leisure physical activity showed to be a protective factor to serum vitamin D deficiency, probably due to greater sun exposure.Funding SourcesSão Paulo Municipal Health Department, FAPESP, CNPq.