I read with great interest the study by Choung et al1 conducted on a population living in Olmsted County, Minnesota. In this community, the prevalence of undiagnosed celiac disease was 1%. Furthermore, to compare the proportion of comorbidities between undiagnosed cases of celiac disease and age- and sex-matched seronegative subjects, a nested case control study was performed. Analyzing the difference of laboratory parameters the authors found lower ferritin levels (P = .01) and cholesterol levels (P = .03) in cases of undiagnosed celiac disease than in controls.