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Although serotonin is not a major player in depression, its precursor is

Molecular Psychiatry volume 28, pages 3155–3156 (2023)Cite this article

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We read with great interest the umbrella review by Moncrieff et al. titled “The serotonin hypothesis of depression: a comprehensive umbrella review of the data” [1]. These authors conclude that serotonin plays no significant role in major depression (MDD) [1], and we completely agree, despite the fact that we [2, 3] and others [4] have repeatedly underscored the importance of low levels of its precursor in MDD.

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References

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Funding

The study was funded by the C2F program, Chulalongkorn University.

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Authors and Affiliations

  1. Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand

    Abbas F. Almulla & Michael Maes

  2. Medical Laboratory Technology Department, College of Medical Technology, The Islamic University, Najaf, Iraq

    Abbas F. Almulla

  3. Department of Psychiatry, Medical University of Plovdiv, Plovdiv, Bulgaria

    Michael Maes

  4. Department of Psychiatry, IMPACT Strategic Research Centre, Deakin University, Geelong, VIC, Australia

    Michael Maes

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  1. Abbas F. Almulla
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  2. Michael Maes
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Both authors contributed to the writing up of the current article.

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Correspondence to Michael Maes.

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Almulla, A.F., Maes, M. Although serotonin is not a major player in depression, its precursor is. Mol Psychiatry 28, 3155–3156 (2023). https://doi.org/10.1038/s41380-023-02092-1

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