Fatty fish and supplements are the greatest modifiable contributors to the serum 25-hydroxyvitamin D concentration in a multiethnic population

Summary Objective Because vitamin D synthesis is lower in a heavily pigmented skin than in a lighter skin, the relative contribution of determinants to the vitamin D concentration might differ between ethnic groups. The aim of this study was to assess the prevalence of vitamin D deficiency and the relative contribution of vitamin D consumption and exposure to sunlight to the vitamin D concentration in a multiethnic population. Design Cross‐sectional study. Patients A total of 613 adults aged 18–65 years from a random sample from general practices in the Netherlands (52°N, 2003–05), stratified according to gender and ethnic group. Measurements Serum 25‐hydroxyvitamin D [25(OH)D], PTH, ethnic group, sunlight exposure, consumption of foods and supplements rich in vitamin D. Results The prevalence (95% confidence interval) of vitamin D deficiency [serum 25(OH)D