What early-life exposures might increase the risk of childhood asthma?
Childhood asthma risk is shaped by a mix of prenatal and early-life exposures. Research points to several factors that may increase the chances of a child developing asthma, including certain medications, chemicals, infections, and lifestyle factors. While no single cause guarantees asthma, avoiding or reducing these exposures where possible may help lower risk.
What the research says
A large Canadian cohort study (CHILD) identified several early-life exposures linked to childhood asthma, including antibiotic use, DEHP phthalate (a chemical in plastics), and mothers' use of cleaning products and disinfectants during pregnancy 3. These exposures were associated with epigenetic changes and altered microbiome and inflammatory markers in children 3.
Other studies highlight additional risk factors. Prenatal factors such as maternal diet and microbiome, as well as postnatal microbial exposures and colonization, contribute to asthma risk 5. Environmental exposures like tobacco smoke, air pollution, and farmyard environments also influence wheezing and asthma development 6. Preterm birth and rapid infant weight gain are other risk factors 6.
While vitamin D supplementation has not been shown to improve lung function in children with asthma 1, lower vitamin D levels have been observed in children with acute asthma exacerbations, though the association was not statistically significant after adjustment 4. Higher ferritin and eosinophil levels were independently linked to exacerbations 4. Childhood asthma itself is associated with a higher risk of obstructive sleep apnea 2.
What to ask your doctor
- Are there specific prenatal or early-life exposures I should avoid to reduce my child's asthma risk?
- Could my child's antibiotic use or my use of cleaning products during pregnancy have contributed to asthma?
- What role does my child's diet or microbiome play in asthma development, and are there steps I can take?
- Should I be concerned about my child's weight gain or preterm birth history in relation to asthma?
- How can I minimize my child's exposure to tobacco smoke, air pollution, and other environmental triggers?
This question is drawn from common patient questions about this topic and answered using cited medical research. We do not provide individualized advice.