Gliadins in particular have been implicated in allergy to wheat, both in IgE-mediated allergy and the non-IgE mediated celiac allergy. IgE antibodies to ω-5-gliadin have been found in children with immediate reactions to ingested wheat, and published results show that increased levels of IgE to ω-5-gliadin correlate with the outcome of food challenges. In a Finnish study, all children with IgE antibodies to ω-5-gliadin reacted with immediate symptoms to wheat challenges, while all patients with delayed or negative challenge test results showed no detectable IgE antibodies to ω-5-gliadin.15 In a Japanese cohort, the presence of elevated ω-5-gliadin-specific IgE antibodies was associated with immediate symptoms with wheat food challenges and also in patients with a strong convincing history of wheat allergy who were not challenged due to risk of anaphylaxis. Furthermore, patients with severe reactions upon challenge had significantly higher levels of ω-5-gliadin-specific IgE antibodies compared to children with mild or moderate symptoms.16 In a multicenter Japanese study, Ebisawa et al. showed a significant relationship between the probability of wheat allergy and the concentration of ω-5-gliadin-specific IgE antibodies with 2.6-fold increased risk.17 In a study of mixed German and American subjects, ω-5-gliadin-specific IgE antibodies did not correlate with food challenge outcomes in patients with suspected allergy. However, the sample size in this study was much smaller than in others, and the German population included more patients with non-IgE mediated wheat allergy with delayed symptoms, almost half of the German cohort.18 Nonetheless, ω-5-gliadin-specific IgE antibodies may differ among populations in Asia, Europe, and the United States due to dietary habits and genetics, and further study is warranted, especially in a larger U.S. cohort.