March 7, 2015 (foodconsumer.org) -- Scientists at University of Ulsan College of Medicine and other universities in Seoul, Korea conducted a study and found evidence suggesting that exposure to antibiotics during infancy may increase the risk of childhood asthma.

The study also identified bronchiolitis and a history of parental asthma as risk factors for asthma in children.

Data used for the study were collected from 7,389 middle school students in eight districts of Seoul, Korea who were surveyed using the International Study of Asthma and Allergies in Childhood questionnaire.

The study found bronchiolitis in the first two years of life and antibiotic usage during infancy and parental asthma were independent risk factors for pediatric asthma.

Specifically, children who used antibiotics and had a history of bronchiolitis together were five times more likely to develop childhood asthma, compared to those who did not use antibiotics nor had bronchiolitis.

The risk increase was higher among children with CC genotype of TLR4 who would have to face nearly six times higher risk for childhood asthma if they used antibiotics and suffered bronchiolitis during infancy.

Other studies have associated use of antibiotics with increased risk of breast cancer.  But a causal relationship has not been established.  (David Liu, PHD)

Lee E, Kwon JW, Kim HB, Yu HS, Kang MJ, Hong K, Yang SI, Jung YH, Lee SH, Choi KY, Shin HL, Hong SA, Kim HY, Seo JH, Kim BJ, Lee SY, Song DJ, Kim WK, Jang GC, Shim JY, Hong SJ.  Association Between Antibiotic Exposure, Bronchiolitis, and TLR4 (rs1927911) Polymorphisms in Childhood Asthma.  Allergy Asthma Immunol Res. 2015 Mar;7(2):167-74.