Tehran University of Medical Sciences Journal of Nutritional Sciences and Dietetics 4 1 2018 01 02 216 216 EN Mehran Rahimlou School of Paramedicine, Jundishapur University of Medical Sciences, Ahvaz,Iran Elham Rayyani Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences, Tehran, Iran Seyed Ahmad Hosseini School of Paramedicine, Jundishapur University of Medical Sciences, Ahvaz,Iran Durdana Husain School of Paramedicine, Jundishapur University of Medical Sciences, Ahvaz,Iran 2018 02 20 2018 05 18 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 reviewof all available studieswas 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 n3 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 diagnosedwith 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. https://jnsd.tums.ac.ir/index.php/jnsd/article/view/216 https://jnsd.tums.ac.ir/index.php/jnsd/article/download/216/201