Quick Navigation


Depression is a chronic state of low mood often associated with hopelessness, apathy, and fatigue. Unlike sadness, depression is a disorder that persists for weeks or months and interferes with daily life.

Our evidence-based analysis on depression features 37 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
Last Updated:


  1. ^ The content of this page was partially adapted from MedlinePlus of the National Library of Medicine.
  2. ^ Sinyor M, Rezmovitz J, Zaretsky A. Screen all for depression. BMJ. (2016)
  3. ^ Ferrari AJ, et al. Burden of depressive disorders by country, sex, age, and year: findings from the global burden of disease study 2010. PLoS Med. (2013)
  4. ^ GBD 2015 Disease and Injury Incidence and Prevalence Collaborators. Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. (2016)
  5. ^ Hirschfeld RM. History and evolution of the monoamine hypothesis of depression. J Clin Psychiatry. (2000)
  6. ^ Krishnan V, Nestler EJ. The molecular neurobiology of depression. Nature. (2008)
  7. ^ Andrews PW, et al. Is serotonin an upper or a downer? The evolution of the serotonergic system and its role in depression and the antidepressant response. Neurosci Biobehav Rev. (2015)
  8. ^ van der Veen FM, et al. Effects of acute tryptophan depletion on mood and facial emotion perception related brain activation and performance in healthy women with and without a family history of depression. Neuropsychopharmacology. (2007)
  9. ^ Malberg JE, et al. Chronic antidepressant treatment increases neurogenesis in adult rat hippocampus. J Neurosci. (2000)
  10. ^ Arumugam V, et al. The impact of antidepressant treatment on brain-derived neurotrophic factor level: An evidence-based approach through systematic review and meta-analysis. Indian J Pharmacol. (2017)
  11. ^ Brites D, Fernandes A. Neuroinflammation and Depression: Microglia Activation, Extracellular Microvesicles and microRNA Dysregulation. Front Cell Neurosci. (2015)
  12. ^ Sanacora G, Treccani G, Popoli M. Towards a glutamate hypothesis of depression: an emerging frontier of neuropsychopharmacology for mood disorders. Neuropharmacology. (2012)
  13. ^ Anacker C, et al. The glucocorticoid receptor: pivot of depression and of antidepressant treatment?. Psychoneuroendocrinology. (2011)
  14. ^ McClung CA. Circadian genes, rhythms and the biology of mood disorders. Pharmacol Ther. (2007)
  15. ^ Psaltopoulou T, et al. Mediterranean diet, stroke, cognitive impairment, and depression: A meta-analysis. Ann Neurol. (2013)
  16. ^ Lee H, Kim S, Kim D. Effects of exercise with or without light exposure on sleep quality and hormone reponses. J Exerc Nutrition Biochem. (2014)
  17. ^ Leone M, et al. Effects of an exercise program on the physiological, biological and psychological profiles in patients with mood disorders: a pilot study. Int J Psychiatry Clin Pract. (2018)
  18. ^ Lo JC, et al. Cognitive Performance, Sleepiness, and Mood in Partially Sleep Deprived Adolescents: The Need for Sleep Study. Sleep. (2016)
  19. ^ Lastella M, Lovell GP, Sargent C. Athletes' precompetitive sleep behaviour and its relationship with subsequent precompetitive mood and performance. Eur J Sport Sci. (2014)
  20. ^ McClung CA. How might circadian rhythms control mood? Let me count the ways. Biol Psychiatry. (2013)
  21. ^ Fried EI. The 52 symptoms of major depression: Lack of content overlap among seven common depression scales. J Affect Disord. (2017)
  22. ^ Rush AJ, et al. The Inventory of Depressive Symptomatology (IDS): psychometric properties. Psychol Med. (1996)
  23. ^ HAMILTON M. A rating scale for depression. J Neurol Neurosurg Psychiatry. (1960)
  24. ^ Montgomery SA, Asberg M. A new depression scale designed to be sensitive to change. Br J Psychiatry. (1979)
  25. ^ Parletta N, et al. A Mediterranean-style dietary intervention supplemented with fish oil improves diet quality and mental health in people with depression: A randomized controlled trial (HELFIMED). Nutr Neurosci. (2019)
  26. ^ Phillips CM, et al. Dietary inflammatory index and mental health: A cross-sectional analysis of the relationship with depressive symptoms, anxiety and well-being in adults. Clin Nutr. (2018)
  27. ^ Cooney GM, et al. Exercise for depression. Cochrane Database Syst Rev. (2013)
  28. ^ Krogh J, et al. Exercise for patients with major depression: a systematic review with meta-analysis and trial sequential analysis. BMJ Open. (2017)
  29. ^ Piercy KL, et al. The Physical Activity Guidelines for Americans. JAMA. (2018)
  30. ^ Bennie JA, et al. Associations between aerobic and muscle-strengthening exercise with depressive symptom severity among 17,839 U.S. adults. Prev Med. (2019)
  31. ^ Chand SP, Kuckel DP, Huecker MR. Cognitive Behavior Therapy (CBT).
  32. ^ Cuijpers P, et al. How effective are cognitive behavior therapies for major depression and anxiety disorders? A meta-analytic update of the evidence. World Psychiatry. (2016)
  33. ^ Beck A, et al. Increasing access to Cognitive Behaviour Therapy in Low and Middle Income Countries: A strategic framework. Asian J Psychiatr. (2016)
  34. ^ Kirsch I, et al. Initial severity and antidepressant benefits: a meta-analysis of data submitted to the Food and Drug Administration. PLoS Med. (2008)
  35. ^ Cipriani A, et al. Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder: a systematic review and network meta-analysis. Lancet. (2018)
  36. ^ Munkholm K, Paludan-Müller AS, Boesen K. Considering the methodological limitations in the evidence base of antidepressants for depression: a reanalysis of a network meta-analysis. BMJ Open. (2019)
  37. ^ Wang SM, et al. Efficacy of antidepressants: bias in randomized clinical trials and related issues. Expert Rev Clin Pharmacol. (2018)