Magnesium Supplement Reference

I’m a big advocate of science-backed supplements to optimize mental and physical performance. These articles represent my own distilled research on effectiveness, risk, and other things to consider before supplementing. To see what supplements I am currently taking, definitely check out the “My Current Supplements” article at the top of this section. Most of the sources are dervived from, which is a great resource, but my intent is to distill it down and add my own research + anecdotes.

What is Magnesium?

Magnesium is an essential dietary mineral that is critical to numerous functions within the human body. The human body is so reliant on magnesium that it stores more than 25g of the mineral across different systems at any given time - with most of this mineral storage occurring in soft tissues.1 More than 50% of the United States is deficient in magnesium because it is relatively difficult to obtain proper amounts of magnesium through diet alone. Older populations are more prone to magnesium deficiency, but supplementation is recommended for anyone who does not eat a ton of nuts or dark leafy greens.

Magnesium Sources

Two places:

  1. Diet - Spinach, various types of nuts, brown rice, and avocados all magnesium rich. However, it is difficult to meet the RDA (300-400mg) for magnesium through diet alone.
  2. Supplements

A report by the US Nutritional Health and Examination Survey in 2006 (Research: 1) found that 60% of Americans are magnesium deficient.2 This is second only to Vitamin D deficiency.

Benefits of Supplementing Magnesium

Benefits are listed from best supported to least supported

  • Protects Against Diabetes - Magnesium makes the pancreas more efficient, which results in lowered blood glucose and increased insulin sensitivity in magnesium deficient non-diabetics.3
  • Lowers Blood Pressure - correcting a magnesium deficiency resulted in a blood pressure drop of 7.1% (systolic) and 4.7% (diastolic) in healthy subjects.4
  • Improves Sleep Quality - Magnesium supplementation increased time spent in slow-wave sleep, which is linked to improvements in overall memory. Also reduced sleeping cortisol levels.5
  • Might Help With ADHD - Strong correlation was found between ADHD and magnesium deficiency in children. No conclusive evidence has been found regarding a causal relationship.6
  • Might Help With Depression - Weaker correlation here between depression and magnesium deficiency. The neat thing is that magnesium may be synergistic with SSRIs, which would improve depression treatments. (Research:4)
  • Might Increase Aerobic Exercise Capacity - One study showed a marked improvement in cardio performance in trained athletes supplementing with magnesium.[^14]

Downsides and Toxicity to Magnesium Supplementation

Magnesium Oxide (the form you don’t want to buy) causes laxative effects when taken orally. It is recommended below to take a non-laxative and higher bioavailable form of magnesium.

It is almost impossible to reach the toxicity level for magnesium, as the kidneys are very efficient at filtering out excess quantities. There are extremely rare cases of magnesium toxicity, but only because the patients kidneys failed. The worst thing that will happen if you take too much will be laxative effects, which is more embarrassing than life threatening.1

Dosages and Timing For Magnesium

Magnesium supplements are a little more complicated than one would think. Magnesium is not easily absorbed by the body on its own, so manufacturers often attach it to a transporting substance so that it can be absorbed. This results in many variants of magnesium supplements that all have differing effectiveness. There are two factors that you should watch out for: elemental magnesium and bioavailability. Elemental magnesium is the actual content of magnesium in the supplement - often this is printed on the bottle. Bioavailability, on the other hand, relates to the effectiveness of the transporting substance. High elemental magnesium and high bioavailability is the goal, since taking tons of huge pills sucks.

List sorted from most recommended to least

  • Magnesium Glycinate - Most recommended. Has a high bioavailability (80%), but low elemental magnesium by weight, so you will be taking a couple large pills daily. The “Glycinate” part helps with sleep, so best taken before bed.7
  • Magnesium Taurinate - Also has a great bioavailability and is very similar to Magnesium Glycinate. The taurine molecule bound to the elemental magnesium makes it a great candidate to take before bed, since taurine can be used to enhance sleep quality.7
  • Magnesium-L-Threonate - Upregulates NMDA receptors and increases brain BDNF levels, which boosts active memory and learning. Only rat studies available, but the nootropics community seems to like it.8
  • Magnesium-L-Orotate - Shown to increase physical performance in triathletes and similar extreme athletes. Not much research on this yet.9
  • Magnesium Oxide - Cheapest, most common option. Magnesium Oxide is the most common form of magnesium supplementation, but has very poor absorption rates (4-5%) and can cause gastro-intestinal distress. You need to take a lot of this to get any of the above benefits.7

Magnesium Glycinate or Taurinate are the most recommended. The optimal time to take these supplements is before bed due to the glycine/taurine acting as sleep-enhancing agents.

Dosing for magnesium is a piece of cake. Just shoot for the recommended daily intake of 300-400mg of elemental magnesium.7 See the “When and how to take” section regarding exactly what this means - picking out the right form of magnesium gets tricky depending on what you are going for.

Conclusion and Recommendations

Magnesium is another major dietary deficiency that can be easily fixed with little cost. The upsides are pretty big in the long run, and honestly the better sleep quality is nice day to day. Overall, highly recommended for daily use.

Recommended Brand: Doctors Best Magnesium Glycinate or Nootropics Depot Magnesium Glycinate. They both rank well in terms of purity and quality.

The cost of magnesium supplementation is right around $0.12 - $0.16 per day. That is cheap enough to justify adding to any supplement stack.

Research / Sources