Magnesium is an essential dietary mineral and one of the common nutritional deficiencies in the world, especially in the US and other western countries. Magnesium has countless roles in the body, including the regulation of heart health, blood pressure, glucose, insulin, and is critical for maintaining mental health.
Magnesium acts as an NMDA antagonist,1www.ncbi.nlm.nih.gov/pmc/articles/PMC1280813/2www.ncbi.nlm.nih.gov/pubmed/6320006 causing a calming effect on the brain.3www.ncbi.nlm.nih.gov/pubmed/197804054www.ncbi.nlm.nih.gov/pubmed/9932380 NMDA antagonists prevent the brain from becoming overstimulated, and this effect can explain why magnesium is so effective for improving mental health.
Magnesium has been shown to improve sleep6 www.ncbi.nlm.nih.gov/pubmed/121639837 www.ncbi.nlm.nih.gov/pubmed/21199787, and deficient levels of magnesium have been strongly implicated in ADHD5www.ncbi.nlm.nih.gov/pubmed/9368236, depression8www.ncbi.nlm.nih.gov/pubmed/192714199www.sciencedirect.com/science/article/pii/S002839080400258811www.ncbi.nlm.nih.gov/pubmed/1882594612www.ncbi.nlm.nih.gov/pubmed/19085527, and anxiety.910www.sciencedirect.com/science/article/pii/S002839081100305411www.ncbi.nlm.nih.gov/pubmed/1882594612 Upon supplementation, magnesium has been shown to reduce all of the above symptoms, which demonstrates its critical role in brain health.
Where to Purchase Magnesium
Magnesium may be purchased at Nootropics Depot.
I recommend Nootropics Depot because they have been around for a long time and have maintained a solid reputation. They have excellent quality control metrics: they do in-house testing as well as independent 3rd-party testing, and they have certificates of analysis available for all of their products.
A standard dose is between 200-400mg of elemental magnesium. The best forms to take are magnesium citrate and magnesium glycinate, which contain 11.23% and 14.10% of elemental magnesium respectively. I prefer to take the magnesium glycinate since glycine actually acts as an NMDA antagonist not unlike magnesium, which means it may be even more effective than magnesium by itself.
If correcting for a deficiency, 400mg of elemental magnesium should be taken for the first week, then 200-300mg would be reasonable for daily doses afterwards. If taking magnesium citrate, 400mg of elemental magnesium would require a dose of 3.6g; with glycinate that dose would be about 2.8g. Magnesium does not generally cause sedation unless you are deficient and take a high dose, so it can be taken at any time of day, though many people prefer to at night to help with sleep.