Omega 3 and 6 oils for primary prevention of allergic disease: systematic review and meta-analysis
Article first published online: 7 APR 2009
© 2009 John Wiley & Sons A/S
Volume 64, Issue 6, pages 840–848, June 2009
How to Cite
Anandan, C., Nurmatov, U. and Sheikh, A. (2009), Omega 3 and 6 oils for primary prevention of allergic disease: systematic review and meta-analysis. Allergy, 64: 840–848. doi: 10.1111/j.1398-9995.2009.02042.x
- Issue published online: 11 MAY 2009
- Article first published online: 7 APR 2009
- Accepted for publication 11 February 2009
- allergic rhinitis;
- food allergy;
- omega oils;
- systematic review
Background: There is conflicting evidence on the use of omega 3 and omega 6 supplementation for the prevention of allergic diseases. We conducted a systematic review evaluating the effectiveness of omega 3 and 6 oils for the primary prevention of sensitization and development of allergic disorders.
Methods: We searched The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, LILACS, PsycInfo, AMED, ISI Web of Science and Google Scholar for double-blind randomized controlled trials. Two authors independently assessed articles for inclusion. Meta-analyses were undertaken using fixed effects modelling, or random effects modelling in the event of detecting significant heterogeneity.
Results: Of the 3129 articles identified, 10 reports (representing six unique studies) satisfied the inclusion criteria. Four studies compared omega 3 supplements with placebo and two studies compared omega 6 supplements with placebo. There was no clear evidence of benefit in relation to reduced risk of allergic sensitization or a favourable immunological profile. Meta-analyses failed to identify any consistent or clear benefits associated with use of omega 3 [atopic eczema: RR = 1.10 (95% CI 0.78–1.54); asthma: RR = 0.81 (95% CI 0.53–1.25); allergic rhinitis: RR = 0.80 (95% CI 0.34–1.89) or food allergy RR = 0.51 (95% CI 0.10–2.55)] or omega 6 oils [atopic eczema: RR = 0.80 (95% CI 0.56–1.16)] for the prevention of clinical disease.
Conclusions: Contrary to the evidence from basic science and epidemiological studies, our systematic review and meta-analysis suggests that supplementation with omega 3 and omega 6 oils is probably unlikely to play an important role as a strategy for the primary prevention of sensitization or allergic disease.