Significant associations have been found between 25(OH)D deficiency and insulin resistance and T2D [28] and, in the earlier publications from the MEDIM population study, significant ethnic differences in insulin action were reported between Iraqi-born immigrants to Sweden and Swedish-born natives, after adjusting for the confounding effect of age, BMI, sex, family history and lifestyle habits [2, 23]. This evidence concerns the gene INS and type 2 diabetes mellitus.