An updated systematic review on the effects of n-3 long-chain polyunsaturated fatty acids on autistic spectrum disorder

Objectives: It has been suggested that omega-3 fatty acids deficiency could play a role in the pathogenesis of several psychiatric disorders, especially autism spectrum disorder (ASD). This systematic review of all available studies was conducted to assess the efficacy of omega-3 fatty acid supplementations on the core features of ASD. Methods: To find the relevant articles, databases including MEDLINE, EMBASE, PsycINFO, PubMed, Scopus and Cochrane between 1966 and December 2016 were searched. The criteria of selecting studies were English language; oral administration of n-3 fatty acids supplements; clinical trials involving human patients with autism; and relationships between omega-3 fatty acids, DHA or EPA supplementation, as well as fish oil, and autism-related clinical- and social-related outcomes. Results: We identified 337 articles in the systematic search, nine articles were finally chosen to be included in the review. Most studies have shown that omega-3 fatty acid supplementation can reduce hyperactivity and social problems in individuals diagnosed with autism. However, no significant association has been reported between omega-3 fatty acid supplementation as compared to placebo in behavioral abnormalities in most of the studies. Conclusion: Based on the available literature, omega-3 fatty acids can act as an effective supplement in individuals with autism.