RESUMO
BACKGROUND: This study was carried out to assess the effects of omega-3 supplementation as an adjunct treatment for eating and psychological symptoms in patients with anorexia nervosa. METHODS: We conducted a systematic review of the literature using the terms 'anorexia nervosa' AND 'Fatty Acids, Omega-3'. Five randomised controlled trials with a total of 144 participants, published between 2003 and 2022, were included. RESULTS: The effects of supplementation of omega-3 on anxiety were standardised mean difference (SMD) 0.79, 95% confidence interval (CI) -0.08 to 1.66; p = 0.08; I² = 3%; two studies, 33 participants; moderate quality of evidence. For depression, the supplementation of omega-3 was SMD: 0.22, 95% CI: -0.50 to 0.93; p = 0.18; I² = 45%; two studies, 33 participants; moderate quality of evidence. For obsessive-compulsive disorder, the supplementation of omega-3 was SMD: -0.22, 95% CI: -0.70 to 2.25; p = 0.36; I² = 0%; three studies, 32 participants; low quality of evidence. CONCLUSION: This research showed that regardless of dose, time or, if associated with other components, the use of omega-3 supplementations as an adjuvant treatment showed no evidence of effect in eating and psychological symptoms in patients with anorexia nervosa.