Pediatrics · Medical Literature
Early-life high-dose omega-3 polyunsaturated fatty acid supplementation reduces risk of childhood asthma/wheezing: A meta-analysis of randomized controlled trials.
Abstract
Asthma, a chronic inflammatory airway disease characterized by wheezing, imposes a substantial global health burden on children. Given the potential of early-life omega-3 polyunsaturated fatty acid (omega-3 PUFA) supplementation as an anti-inflammatory intervention to prevent childhood asthma and wheezing, this meta-analysis aims to clarify its efficacy and investigate dose-dependency. This systematic review and meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three reviewers independently evaluated the studies, extracted data, and assessed bias using the Jadad scale. The outcomes included the risk of asthma/wheezing: pooled odds ratios (ORs) were calculated using fixed-effects models, along with sensitivity/subgroup analyses and dose-response meta-regression. Twelve randomized controlled trials (RCTs) involving 4,156 participants showed no overall association between omega-3 PUFA and a reduced risk of asthma/wheezing (odds ratio [OR]: 1.00; 95% confidence interval [CI]: 0.84-1.18). However, high-dose supplementation (≥1,200 mg/day) significantly decreased the risk (OR: 0.66; 95% CI: 0.46-0.94). Similarly, high-dose eicosapentaenoic acid (EPA≥1,000 mg/day) also significantly reduced the risk (OR: 0.67; 95% CI: 0.46-0.97). Dose-response analysis confirmed a linear relationship (p=0.002), indicating a 26.6% reduction in risk for every 1,000 mg/day increase in dose (OR: 0.734; 95% CI: 0.602-0.896). Subgroup analyses revealed no heterogeneity with respect to study location, allergy risk, or follow-up duration. Early-life omega-3 PUFA supplementation reduces childhood asthma/wheezing risk in a dose-dependent manner. High-dose regimens, particularly those involving EPA, provide substantial protection, suggesting a potential clinical strategy for prevention, although further validation is required.
Clinical relevance
Childhood asthma represents a major global health burden, and there is an unmet need for safe, early preventive interventions targeting its inflammatory pathogenesis. This meta-analysis of 12 RCTs (n=4,156) addresses the longstanding uncertainty around omega-3 PUFA supplementation efficacy by specifically interrogating dose-dependency — a dimension previously underexplored in pooled analyses. Clinicians managing high-risk pregnancies or infants with atopic predisposition now have quantitative dose thresholds to inform counseling and preventive strategies.
Key findings
1. Overall omega-3 PUFA supplementation showed no statistically significant reduction in childhood asthma/wheezing risk across 12 RCTs (n=4,156): pooled OR 1.00 (95% CI: 0.84–1.18), indicating neutral effect at aggregate doses. 2. High-dose omega-3 PUFA supplementation (≥1,200 mg/day) significantly reduced the risk of asthma/wheezing: OR 0.66 (95% CI: 0.46–0.94), representing a 34% relative risk reduction. 3. High-dose EPA specifically (≥1,000 mg/day) also conferred significant protection: OR 0.67 (95% CI: 0.46–0.97), closely mirroring the effect seen with total high-dose omega-3 PUFA. 4. Dose-response meta-regression confirmed a statistically significant linear relationship between omega-3 PUFA dose and risk reduction (p=0.002): every 1,000 mg/day increase in dose was associated with a 26.6% reduction in asthma/wheezing risk (OR: 0.734; 95% CI: 0.602–0.896). 5. Subgroup analyses revealed no significant heterogeneity by study geographic location, baseline allergy risk status, or duration of follow-up, suggesting the dose-dependent effect is robust across diverse populations and study designs. 6. Study quality was assessed using the Jadad scale with three independent reviewers, and analyses were conducted under fixed-effects models per PRISMA guidelines; sensitivity analyses supported the stability of high-dose findings.
Practice implications
For clinicians counseling pregnant women or caregivers of high-risk infants, these data suggest that omega-3 PUFA supplementation should target a threshold of ≥1,200 mg/day total omega-3 (with EPA ≥1,000 mg/day) to achieve meaningful asthma/wheezing risk reduction, as lower aggregate doses appear ineffective. Patient selection should prioritize those with known atopic or allergic risk factors, and supplementation initiated in early life (prenatal or postnatal periods as per individual RCT protocols) appears to be the relevant intervention window. While the linear dose-response relationship is compelling, further large-scale RCTs are warranted to validate optimal dosing regimens, define the precise intervention window, and establish long-term safety before universal prophylactic recommendations can be issued.