Our rating
 Question mark: This treatment has not been properly researched. It is not possible to say whether they are useful or not.


The rating system

  • 3 smiliesThese treatments are very useful. They are strongly supported as effective by scientific evidence.
  • 2 smiliesThese treatments are useful. They are supported by scientific evidence as effective, but the evidence is not as strong.
  • 1 smileyThese treatments are promising and may be useful. They have some evidence to support them, but more evidence is needed to be sure they work.
  • No smiley On the available evidence, these treatments do not seem to be effective.
  • Question markThese treatments have not been properly researched. It is not possible to say whether they are useful or not.
  • Exclamation MarkSafety or other concerns have been raised for the use of these treatments.

What is it?

Magnesium is an essential trace element found in many foods. Magnesium is used in many different processes in the body.

How does it work?

It is thought that magnesium deficiency may contribute to depression symptoms in some people. Treating this deficiency with magnesium supplements may lead to improvements in depression symptoms.

Is it effective?

There have been several small studies looking at the use of magnesium to improve mood, but the findings of these studies are mixed. Review of studies which looked at the treatment of depression using magnesium either by itself or in addition to other treatments have found inconsistent results.

More studies of higher quality are needed to better understand the effects of magnesium on depression.

Are there any disadvantages?

While magnesium is generally well tolerated there have been some reported side effects from magnesium, such as abdominal pain and diarrhea. Dietary supplements, including magnesium, may have negative interactions with prescribed medications or other supplements. They should always be taken under the supervision of a health care professional. 

Where do you get it?

Magnesium supplements can be purchased from a chemist and some supermarkets. If you think you might have a magnesium deficiency, it is important to discuss this with your doctor and have a blood test to check.


Given the lack of evidence on magnesium it cannot be recommended as a treatment for depression.

Key references

  • Botturi A, Ciappolino V, Delvecchio G, Boscutti A, Viscardi B, Brambilla P. The Role and the Effect of Magnesium in Mental Disorders: A Systematic Review. Nutrients. 2020;12(6).
  • Cheungpasitporn W, Thongprayoon C, Mao MA, Srivali N, Ungprasert P, Varothai N, et al. Hypomagnesaemia linked to depression: a systematic review and meta-analysis. Internal Medicine Journal. 2015; 45(4): 436-40.
  • Phelan D, Molero P, Martinez-Gonzalez MA, Molendijk M. Magnesium and mood disorders: systematic review and meta-analysis. BJPsych Open. 2018; 4(4): 167-79.
  • You HJ, Cho SE, Kang SG, Cho SJ, Na KS. Decreased serum magnesium levels in depression: a systematic review and meta-analysis. Nord J Psychiatry. 2018; 72(7): 534-41.

Last reviewed and updated: 7 August 2023