Effects of Magnesium Supplementation on Unipolar Depression: A Placebo-Controlled Study and Review of the Importance…
When magnesium was tested double-blind on top of an antidepressant, it made no difference to depression scores — is adding it to my treatment worth it, or just an extra pill?
Well-supported by good-quality research. how we score evidence
Caveat on this rating: The authors' own stated limitation is the small sample: 37 people cannot rule out a modest real benefit, so this is an absence of evidence rather than firm evidence of absence. The 120 mg/day dose is also low relative to the 248 mg used in the Tarleton trial, which the authors themselves flag as a possible explanation.
Oral magnesium sold for mood, anxiety, or sleep is a dietary supplement under the Dietary Supplement Health and Education Act of 1994 (DSHEA).
Thirty-seven patients with recurrent depressive disorder in a depressive episode were randomized, double-blind, to fluoxetine plus 120 mg/day of magnesium ions or fluoxetine plus placebo for eight weeks. There was no significant difference between the groups on the Hamilton Depression Rating Scale at any point, and no difference in serum magnesium either. A secondary multivariate model suggested magnesium augmentation was among several factors associated with better odds of response, but that is an exploratory analysis in 37 people and does not overturn the trial's negative primary result.
Worth asking
When magnesium was tested double-blind on top of an antidepressant, it made no difference to depression scores — is adding it to my treatment worth it, or just an extra pill?
Source
Effects of Magnesium Supplementation on Unipolar Depression: A Placebo-Controlled Study and Review of the Importance of Dosing and Magnesium Status in the Therapeutic Response. — Ryszewska-Pokraśniewicz B, Mach A, Skalski M, et al. (2018)
Indexed peer-reviewed journal
Read the source: https://doi.org/10.3390/nu10081014
DOI: 10.3390/nu10081014
How this was scored
- Study design
- Randomised controlled trial
- Funding
- Independently funded
- Published in
- Indexed peer-reviewed journal
- Sample size
- 37
- Preregistered
- No
- Conflicts disclosed
- Yes
- Independent of proponent
- Yes
- Retracted
- No
Read the full scoring rubric, including what it can't tell you.
Published August 19, 2026.
Where we put this study in context
Questions
How strong is the evidence behind this?
Resolv rates this source "strong evidence". Well-supported by good-quality research. It scores 74 out of 100 on our published rubric. One caveat travels with that badge: The authors' own stated limitation is the small sample: 37 people cannot rule out a modest real benefit, so this is an absence of evidence rather than firm evidence of absence. The 120 mg/day dose is also low relative to the 248 mg used in the Tarleton trial, which the authors themselves flag as a possible explanation. The score is calculated from recorded facts about the source — study design, funding, publication venue, sample size, preregistration — not typed in by an editor.
What is the source for this?
Effects of Magnesium Supplementation on Unipolar Depression: A Placebo-Controlled Study and Review of the Importance of Dosing and Magnesium Status in the Therapeutic Response. — Ryszewska-Pokraśniewicz B, Mach A, Skalski M, et al. (2018). Published in: Indexed peer-reviewed journal. DOI: 10.3390/nu10081014. The full source is linked on this page so you can read it yourself.
Who paid for this research, and does that matter?
Study design: Randomised controlled trial. Funding: Independently funded. The researchers were independent of whoever benefits from the result. Industry sponsorship is one of the most reliably measured biases in medicine, which is why funding carries real weight in the score rather than sitting in a footnote.
Is magnesium, magnesium glycinate, magnesium citrate, magnesium oxide, magnesium chloride, magnesium aspartate, magnesium l-threonate, magtein, epsom salts FDA approved for this use?
No. Its current status is: Not FDA-evaluated for this use. Oral magnesium sold for mood, anxiety, or sleep is a dietary supplement under the Dietary Supplement Health and Education Act of 1994 (DSHEA).
Is this medical advice?
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.
This is information to bring to your prescriber, not medical advice and not a reason to change anything on your own. Nothing here is an instruction to stop or reduce a medication. If you are in crisis, call or text 988.