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

What does this rating mean?

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.
  • These treatments are not recommended and could be dangerousSafety 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 studies looking at the use of magnesium to improve mood, but the findings of these studies are mixed.

Some small studies have found that magnesium can be effective at reducing depression symptoms in people with both depression and magnesium deficiencies. However, larger studies have not been able to find a clear link between magnesium intake and depression symptoms.

More studies of better 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

  • Barragan-Rodriguez L, Rodriguez-Moran M, Guerrero-Romero F. Efficacy and safety of oral magnesium supplementation in the treatment of depression in the elderly with type 2 diabetes: a randomized, equivalent trial. Magnesium Research. 2008; 21(4): 218-23.
  • 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.
  • Eby GA, Eby KL. Rapid recovery from major depression using magnesium treatment. Medical Hypotheses. 2006; 67(2): 362-70.
  • Martinez-Gonzalez MA, Sanchez-Villegas A. Magnesium intake and depression: the SUN cohort. Magnesium Research. 2016; 29(3): 102-11.
  • Mehdi SM, Atlas SE, Qadir S, Musselman D, Goldberg S, Woolger JM, et al. Double-blind, randomized crossover study of intravenous infusion of magnesium sulfate versus 5% dextrose on depressive symptoms in adults with treatment-resistant depression. Psychiatry and Clinical Neurosciences. 2017; 71(3): 204-11.
  • 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.
  • Rajizadeh A, Mozaffari-Khosravi H, Yassini-Ardakani M, Dehghani A. Effect of magnesium supplementation on depression status in depressed patients with magnesium deficiency: A randomized, double-blind, placebo-controlled trial. Nutrition. 2017; 35: 56-60.
  • Tarleton EK, Littenberg B, MacLean CD, Kennedy AG, Daley C. Role of magnesium supplementation in the treatment of depression: A randomized clinical trial. PloS One. 2017; 12(6): e0180067.
  • 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: 1 November 2019