The role of fish intake on asthma in children: A meta-analysis of observational studies

BACKGROUND: The evidence is mixed on the use of long chain Omega-3 fatty acids in the prevention and management of childhood asthma. METHODS: We conducted a systematic search and meta-analysis investigating the role of fish intake, the main dietary source of long chain omega-3 fatty acids, on asthma in children. RESULTS: A total of 1119 publications were identified. Twenty-three studies on fish intake in association with childhood asthma were included in the final review. In 15 of 23 studies, early introduction of fish (6-9 months) and regular consumption (at least once a week) improved asthma symptoms and reduced risk in children 0-14 years as compared to no fish consumption; 6 of 23 showed no effect and 2 of 23 studies suggest adverse effects. Meta-analysis revealed an overall "beneficial effect" for "all fish" intake on "current asthma" [OR: 0.75; 95%CI: 0.60-0.95] and "current wheeze" [OR: 0.62; 95%CI: 0.48-0.80] in children up to 4.5 years old. An overall protective effect of "fatty fish" intake as compared to "no fish" intake in children 8-14 years old was also observed [OR: 0.35; 95%CI: 0.18-0.67]. CONCLUSION: This meta-analysis suggests that introduction of fish early in life (6-9 months) and regular consumption of all fish (at least once a week) reduces asthma and wheeze in children up to 4.5 years old, while fatty fish intake may be beneficial in older children. Future well-designed clinical trials are recommended to confirm the promising findings documented in this literature analysis