Maternal caffeine intake during pregnancy and risk of food allergy in young Japanese children.

AIM: To examine the association between maternal caffeine intake during pregnancy and the development of food allergy in young Japanese children up to 3 years of age. METHODS: The study involved 1522 mother-child pairs. Data on maternal caffeine intake during pregnancy were assessed with a validated diet history questionnaire. Food allergy was defined by a self-reported claim of having a physicians' diagnosis of food allergy or of having an acute reaction to a food. RESULTS: Compared with the lowest tertile of maternal caffeine intake during pregnancy, the second tertile, but not the highest tertile, was significantly associated with an increased risk of food allergy. Further adjustment on suspicion or diagnosis of atopic eczema at around 4 months postpartum in a follow-up survey did not substantially change the association between maternal caffeine intake during pregnancy and the risk of food allergy in children: further adjusted hazard ratios (95% confidence intervals) for the second (T2), the highest tertiles (T3) and the second and the highest tertiles combined (T2 + T3) were 1.46 (1.10-1.96), 1.16 (0.85-1.56) and 1.31 (1.01-1.70), respectively. CONCLUSIONS: Our findings suggest that maternal caffeine intake during pregnancy may be positively associated with the risk of food allergy in children.