In this explainer post, Dr. Alison Smith breaks down the findings from Dr. Powers’ white paper on magnesium absorption.
Natural Calm has been on a quest to publish the truth about magnesium absorption.
To get an unbiased, authoritative perspective, they hired Dr. Jon Paul Powers, a microbiologist, partner, and scientific advisor with Gowling WLG in Ottawa, to write a scientific white paper on the effectiveness of magnesium citrate in comparison to other forms of magnesium on the market using data from all the current peer-reviewed literature about magnesium absorption.
Dr Powers happens to also be a former unit head and assessment officer for the National Health Products Directorate of Health Canada. Needless to say, he’s a highly qualified scientific expert capable of illuminating the truth about magnesium supplements.
Prerequisite: Understanding the Different Types of Magnesium Supplements
To understand Dr. Powers’ review of the science, you need to understand the forms in which magnesium supplements are available.
Magnesium supplements contain a variety of different magnesium salts. There isn’t just one type of magnesium salt on the market.
In general, magnesium salts are classified into two major types: organic and inorganic.
Organic magnesium salts are created in a laboratory by combining an inorganic magnesium salt with either an acid or an amino acid (a protein). For example, magnesium citrate is created by combining magnesium with citric acid, and magnesium glycinate is created by combining magnesium with the amino acid, glycine.
Inorganic magnesium salts are naturally derived from harvested earth and rock sources.
** Important to know ** — Natural Calm contains magnesium citrate. The magnesium citrate is created when you dissolve powdered magnesium carbonate (a mineral sourced from deep in the ocean) with citric acid in water. The reaction takes place quickly when dissolved in hot water, and more slowly in cooler water.
Organic Magnesium Salts Commonly Used in Supplements
Magnesium that contains an acid:
- Mg Citrate (Natural Calm)
- Mg Gluconate
- Mg Malate
- Mg Orotate
- Mg Ascorbate
- Mg Lactate
- Mg Fumerate
Magnesium that contains an amino acid:
- Mg Glycinate
- Mg Pidolate
- Mg Taurate
- Mg Glutamate
- Mg Aspartate
- Mg Threonate
Inorganic Magnesium Salts Commonly Used in Supplements
- Mg Chloride
- Mg Carbonate
- Mg Oxide
- Mg Sulfate
Ok, now that we have the Magnesium 101 covered, let’s do a re-cap on what the published research really says – that is, the peer-reviewed research available in scientific journals. I’ll then move on to the new results from the clinical trial.
What the Published Research Says About Magnesium Absorption
To summarize Dr. Power’s review of the literature:
- There has never been any scientific study comparing magnesium glycinate against magnesium citrate. In fact, very few scientific studies have compared magnesium glycinate against other magnesium salts at all.
- Which type of magnesium salt is the best: organic or inorganic? Well, research tells us that organic magnesium salts –– the ones that contain an acid or an amino acid –– are more soluble, absorbable, and bioavailable than inorganic magnesium salts.  Ranade and Somberg (2001). Am J Ther. 8(5), 345-57.
- Magnesium citrate can withstand drastic acidic changes in the gut; therefore, giving it more time to be absorbed and to become bioavailable.  Lindberg et al. (1990). J Amer Col Nutr. 9(1), 48-55.
- Magnesium citrate is more absorbable and bioavailable than inorganic magnesium oxide. Lindberg et al. (1990) J Amer Col Nutr 9(1), 48-55.
- Magnesium citrate is more absorbable and bioavailable than an amino acid chelate against which it was tested in a study. (Magnesium glycinate is an amino acid chelate, so this is indirect evidence that magnesium citrate might be more effective than magnesium glycinate, but we need more research…and that’s coming up. Stay tuned!)  Walker et al. (2003) Magnes Res 6(3), 183-91.
What Does this Mean About the Difference Between Magnesium Citrate and Magnesium Glycinate?
So, what conclusions can we come to about magnesium absorption, based only on the scientific literature?
- Overall, there is very little research comparing magnesium salts against each other. This is a problem, and it contributes to the issue of misinformation and bogus claims.
- We definitely know that organic magnesium salts are more effective than inorganic magnesium salts, but when it comes to comparing ALL of the organic magnesium salts against each other, we simply do not have enough published research to say which is more effective.
- Magnesium glycinate isn’t any more effective than other organic magnesium salts including magnesium citrate.
- Magnesium citrate can significantly absorb into the bloodstream to become bioavailable. [2,3]e4 Lindberg et al. (1990). J Amer Col Nutr. 9(1), 48-55; Walker et al. (2003) Magnes Res 6(3), 183-91.
- The claims about magnesium glycinate are not based on science and are therefore bogus information.
We know this much from the existing, peer-reviewed, published science.
Soon, we’ll also be able to share the results of the new clinical study comparing magnesium supplements head-to-head.
- Ranade and Somberg (2001). Am J Ther. 8(5), 345-357.
- Lindberg et al. (1990). J Amer Col Nutr. 9(1), 48-55.
- Walker et al. (2003) Magnes Res 6(3), 183-91.