Our body relies on magnesium (Mg) for multiple functions. It is a cofactor for more than 325 enzyme systems helping in various biochemical reactions – including blood pressure regulation, glucose control, protein synthesis, and mood stabilization. [Source: IMMH]
Over the years, many studies and researches have also linked magnesium to depression, anxiety, and ADHD. So, if you suffer from depression or other mental health disorders it might be due to magnesium deficiency. 
Note: Magnesium deficiency may not be the only cause of your depression, but it plays a significant role in mood and stress management.
Therefore, it is essential to maintain adequate magnesium levels to prevent mood irregularities like feeling low, anxious, or depressed.
Despite its importance, many people suffer from subclinical magnesium deficiency (aka Hypomagnesemia). This common occurrence in clinical medicine often goes undetected because magnesium levels are rarely evaluated. 
Recent data indicates that 10%-30% of the population in developed countries has a subclinical magnesium deficiency. Moreover, a review of around 30 plus articles concluded that magnesium deficiency was a possible global public health concern for adults.
Since most people are unaware of magnesium deficiency, it is highly recommended to take magnesium supplements to maintain adequate Mg levels, thus, ensuring a healthy mind and body. 
Impact of Low Magnesium Levels on The Brain
In terms of magnesium deficiency and brain health connection, low magnesium levels have been linked to: 
- Higher levels of stress
- Insomnia or sleep disturbances
- Headaches or muscle pain/tightness
Magnesium deficiency in the brain contributes to the symptoms mentioned above due to:
- Overstimulation of Excitatory Neurotransmitters
Regulation of Excitatory neurotransmitters is directly involved in mental health and mood disorders. Excess excitatory transmitters can cause overexcitation of brain cells, leading to poor cognitive performance and unhealthy neurological conditions. [Source: IJPSR]
Magnesium regulates these neurotransmitters but its deficiency enhances the activity of the stimulating transmitters and weakens calming receptors – especially gamma-aminobutyric acid (GABA) receptors. Thus, resulting in a more restless and anxious state.
- Increased Production of Stress Hormones
How Magnesium Deficiency Worsens Depression
As stated earlier, magnesium plays a huge role in brain chemistry and impacts mood regulation through many enzymes, pathways, hormones, and neurotransmitters. So, those with magnesium deficiency may experience a multitude of physical and emotional symptoms.  Some can not only complicate and worsen depression but also cause it; these include:
- Premenstrual dysphoric disorder (PMDD) and Premenstrual syndrome (PMS)
- Lower back pain
- Migraines and general headaches
- Chest pain (particularly during an anxiety attack)
- Muscle aches
- Joint pain
- Digestive issues or Irritable Bowel Syndrome (IBS)
- Fatigue and exhaustion
- Issues with sleep
- Low energy and motivation
- Poor concentration
From A Meta-Analysis Study:
An article in The Journal of the American Board of Family Medicine found a deep correlation between low magnesium levels and depression by testing the National Health and Nutrition Examination Survey data set from 2004 to 2010. It indicated a 95% risk ratio (RR) of low magnesium intake and presence of depression. 
From: Rapid recovery from major depression using magnesium treatment by George A Eby et al. Med Hypotheses. 2006
Another analysis of over 8,800 people found that people with low magnesium intake have a 22% higher risk of suffering from depression.
From a Clinical Trial:
The Journal of PLoS One published a randomized clinical trial in 2017 revealing that magnesium chloride intake significantly improved depressive symptoms. The study also concluded that the participants taking antidepressants experienced improved benefits with magnesium, proving it useful in conjunction with antidepressants.
Benefits of Taking Magnesium For Depression
The beneficial effects of magnesium supplements on mood and depression are so well-known that it has attracted nicknames like ‘the original chill pill,’ ‘nature’s valium,’ and the ‘mind mineral.’
Bassem El-Khodor, Ph.D., has conducted various studies linking magnesium to chronic health disorders. He states that magnesium is ‘the forgotten nutrient, and its supplementation can significantly reduce depression and its symptoms compared to placebo. 
Studies show that restoring normal levels of magnesium (magnesium repletion) creates positive changes in both mental and physical health; these include:
- Better mood and cognition
- Healthy eating behavior
- Healthy stress responses
- Lower risk of depression
- Improved quality of sleep
- Better efficacy of other modalities (such as depression medication)
What Can You Do to Improve Your Magnesium Levels?
Foods high in magnesium include:
- Leafy greens
- Dark chocolate
- Whole grains
It would also be best if you got your magnesium levels checked. If you have low magnesium, you can take magnesium supplements. According to NHS UK, a healthy daily magnesium dose for men (19 to 64 years) is 300 mg a day and 270mg a day for women (19 to 64 years).
Remember: Always consult your psychologist, nutritionist, naturopath, or GP before making any changes to your regimen or diet. Also, avoid taking any supplements without your doctor’s recommendation if you are already under treatment for depression or any mental health disorder.
- Institute of Pharmacology Polish Academy of Sciences. Published by Elsevier Urban & Partner (2013). Magnesium in depression. Retrieved from https://www.sciencedirect.com/science/article/abs/pii/S1734114013710326
- Published by Emily K. Tarleton, Benjamin Littenberg, Charles D. MacLean, Amanda G. Kennedy, and Christopher Daley (2017). Role of magnesium supplementation in the treatment of depression: A randomized clinical trial. Retrieved from https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0180067
- Rapid recovery from major depression using magnesium treatment by George A Eby et al. Med Hypotheses. 2006 https://pubmed.ncbi.nlm.nih.gov/1654278/
- The Journal of the American Board of Family Medicine March. Published by Emily K. Tarleton and Benjamin Littenberg (2015). Magnesium Intake and Depression in Adults. Retried from https://www.jabfm.org/content/28/2/249.short
- Published by Marie-Laure Derom, Carmen Sayón-Orea, José María Martínez-Ortega & Miguel A. Martínez-González (2013). Magnesium and Depression: A Systematic Review. Retrieved From https://www.tandfonline.com/doi/full/10.1179/1476830512Y.0000000044
- Department of Applied Pharmacy, Medical University of Lublin. Published by Anna Serefko, Aleksandra Szopa, Ewa Poleszak (2016). Magnesium in Depression. Retried From https://www.jle.com/en/revues/mrh/e-docs/magnesium_and_depression_308520/article.phtml
- Published by George A. Eby, Karen L. Eby, and Harald Murk (2011). Magnesium in the Central Nervous System. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK507265/
- Published by Afsaneh Rajizadeh, Hassan Mozaffari-khosravi and Mojtaba Yassini (2016). The Effect of Magnesium Supplementation on Depression Status in Depressed Patients with Magnesium Deficiency: A Randomized, Double-blind, Placebo-Controlled Trial. Retrieved from https://www.researchgate.net/publication/309886398_The_Effect_of_Magnesium_Supplementation_on_Depression_Status_in_Depressed_Patients_with_Magnesium_Deficiency_A_Randomized_Double-blind_Placebo-Controlled_Trial