A number of observational and review studies have examined omega-3 fatty acids in relation to asthma prevalence, airway inflammation, and respiratory symptoms.

A review published in the European Journal of Clinical Nutrition (2005; 59(12):1335–1346) summarized research investigating omega-3 fatty acid supplementation and asthma. The authors discussed evidence suggesting that fish oil intake may influence inflammatory pathways and airway function, based on findings from both experimental and observational studies.

Dietary intake of omega-3 fatty acids during pregnancy has also been explored. Research published in the A study published in the International Journal of Tuberculosis and Lung Disease (2007;11:103–109) evaluated 1,002 pregnant Japanese women and found that higher fish intake and a greater ratio of omega-3 to omega-6 fatty acids were associated with a lower prevalence of asthma.

Population-level dietary patterns have been examined as well. A study published in Clinical and Experimental Allergy (2007; 37(11):1616–1623) assessed dietary habits in 16,187 adults aged 23 to 54 years. The investigators reported that modest fish consumption was associated with a lower risk of developing asthma, while individuals who reported never consuming fish during childhood had a higher risk of early-onset asthma.

Interventional research in early life has also been reported. A study published in Pediatric Allergy and Immunology (2004; 15:517–522) examined omega-3 fatty acid exposure in infants born to mothers considered at increased risk of having a child with asthma. In this study, 616 newborns were assigned to receive either 500 mg per day of fish oil or placebo. Breastfed infants did not receive supplementation until six months of age, reflecting the presence of omega-3 fatty acids in breast milk. At 18 months of age, 376 children were evaluated. Higher blood levels of omega-3 fatty acids were associated with fewer asthma symptoms, reduced nocturnal coughing, and fewer physician visits related to asthma.

Taken together, these studies describe associations between omega-3 fatty acid intake, dietary patterns, and asthma-related outcomes across different populations and life stages. The findings vary by study design, population, and exposure assessment, but collectively reflect sustained research interest in the relationship between fatty acid balance and respiratory health.