Omega-3 fatty acids and anxiety: A systematic review of the possible mechanisms at play

Nutr Neurosci. 2020 Jul;23(7):494-504. doi: 10.1080/1028415X.2018.1525092. Epub 2018 Sep 28.


Introduction: Anxiety is prevalent, costly, and associated with significant adverse outcomes. The importance of nutrition is underestimated in the management of mental health disorders. In particular, omega-3 fatty acids (ω-3 FAs) are a critical component for healthy development and have been shown to reduce anxiety symptoms. Objective: This paper reviews the current state of the research to identify potential mechanisms underlying the relationship between ω-3 FAs and anxiety reduction. Method: Studies were identified using PubMed, PsycINFO, and CINAHL databases. Results: Of the 197 full-text studies screened, six met criteria for inclusion. Four mechanisms were identified based on primary outcomes reported by each study, Inflammatory Response, Brain-Derived Neurotrophic Factor (BDNF), Cortisol, and Cardiovascular Activity. Conclusion: Five key recommendations are provided to guide future research examining ω-3 FAs and anxiety. They include: (1) standardization of dosage and duration of ω-3 supplementation, (2) more rigorous measurement of variables, (3) effective blinding of participants, (4) designing experiments that test mediation, and (5) increasing sample diversity.

Keywords: Anxiety; Brain-derived neurotrophic factor; Inflammation; Omega-3 fatty acids.

Publication types

  • Systematic Review

MeSH terms

  • Anxiety / complications
  • Anxiety / diet therapy*
  • Anxiety / physiopathology*
  • Brain-Derived Neurotrophic Factor / metabolism
  • Dietary Supplements
  • Fatty Acids, Omega-3 / administration & dosage*
  • Humans
  • Hydrocortisone / metabolism
  • Inflammation / complications
  • Stress, Physiological


  • Brain-Derived Neurotrophic Factor
  • Fatty Acids, Omega-3
  • BDNF protein, human
  • Hydrocortisone