Gut permeability to antigens is immature at birth, and while early administration of antigenic foods delays its maturation, breast-feeding accelerates it. We aimed to evaluate whether exposure to antigenic foods in early life is associated with a predisposition for immunoglobulin A nephropathy (IgAN). Three groups of children with IgAN (group 1), non-IgA glomerulopathies (group 2), and healthy controls (group 3) were formed. Parents filled out a questionnaire regarding gestational and postnatal ages, birth weight, and feeding by breast milk, formula, cow's milk, and complementary foods. All groups were similar for age, gender, birth weight, rate and duration of breast-feeding, and rate of formula feeding. Cow's milk consumption rate was higher in groups 1 and 2 than in group 3. Whereas introduction of formula was earlier in groups 1 and 2 than in group 3, feeding by cow's milk and weaning were earlier in group 1 than in the other groups. The respective best cutoff ages were 3.5 [odds ratio (OR) 28)], 3.75 (OR 5.7), and 5.5 (OR 10.5) months for formula, cow's milk, and complementary foods, respectively, for predicting the presence of IgAN. The results of this preliminary study indicate that early introduction of antigenic foods might increase the risk of future primary IgAN.