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HEALTH

The Claim

There is insufficient scientific evidence to conclude that depression is caused by neurotransmitter changes in the brain.

Verified by Lenz ·

The Short Version

Current evidence does not justify concluding that depression is caused by neurotransmitter changes alone. The strongest reviews find the classic serotonin/chemical-imbalance theory unproven, while major medical institutions describe depression as multifactorial and not fully understood. Neurotransmitters are involved in depression biology, but causation has not been established.

Caveats

  • Most direct evidence addresses serotonin and monoamines; the claim is broader than that literature alone.
  • Neurotransmitter abnormalities can be associated with depression severity without showing they are the primary cause.
  • The claim should not be read as saying neurotransmitters are irrelevant to depression or its treatment.

The Receipts

  1. The serotonin theory of depression: a systematic umbrella review of the evidence

    Nature

  2. Once more with feeling: what does the evidence say about the serotonin theory of depression?

    The BMJ

  3. History and evolution of the monoamine hypothesis of depression

    PubMed

  4. Serotonin and depression: A disconnect between the advertisements and the scientific literature

    PubMed

  5. Monoamine Hypotheses of Mood Disorders - Basic Neurochemistry

    NCBI Bookshelf

  6. Depression

    World Health Organization

  7. Depression

    National Institute of Mental Health

  8. Rethinking Depression—Beyond Neurotransmitters: An Integrated Psychiatry Approach

    Frontiers in Psychiatry (via PMC)

  9. Analysis: Depression is probably not caused by a chemical imbalance in the brain - new study

    UCL

  10. What causes depression?

    Harvard Health

+ 19 more sources — see the full list on Lenz

Filed Under

Depression

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