Are You Being Misled About Magnesium?

published by Anna O'Byrne on in

Are You Being Misled About Magnesium?

Magnesium is a hot topic these days. People are finally realizing that it’s one of the most important nutrients for health.

But some magnesium marketers are going a little too far. We’re trying to be diplomatic here, but …certain claims are completely unfounded.

If you scroll to the very bottom of this post, for example, you’ll read a very surprising admission by a Naturopathic Doctor who works for a big, Canadian magnesium glycinate brand.

Let’s start with the “absorbability” claims, because that’s where some companies are getting creative with their marketing.

The Facts on Magnesium Absorbability

Research shows that absorbability is what matters when it comes to magnesium supplementation. Many brands claim higher absorption, but what does the science say?

Natural Calm Canada commissioned research by a scientific advisor and PhD in microbiology, Dr. Jon-Paul Powers – formerly of the National Health Products Directorate, Health Canada.

Here, we share the findings from his review of the published research on magnesium absorption.

What Dr. Powers’ Research Shows

As concisely as possible, these are the need-to-know facts on magnesium absorption:

  • Fact: Magnesium supplements that are more soluble are more absorbable.
  • Myth: Magnesium citrate is flushed out of the body and not absorbed.
  • Fact: Studies show that magnesium citrate is very absorbable and directly increases blood plasma and salivary levels of magnesium.
  • Myth: Magnesium needs an amino acid to be absorbed, so magnesium chelates are better.
  • Fact: If anything, the current research shows that magnesium chelates are less absorbable than organic magnesium salts, like magnesium citrate.

If you’re wondering how we arrived at these conclusions, read on.

All Magnesium Forms Are Not Equal

To understand the facts about magnesium absorption, you first have to know the basic forms in which magnesium supplements are available. The three main types of magnesium in oral supplements are:

  • Inorganic magnesium salts, such as magnesium oxides, carbonates, chlorides and hydroxides;
  • Organic magnesium salts, including magnesium citrates (like Natural Calm), lactates, and gluconates; and
  • Magnesium amino acid chelates, like magnesium glycinate, bisglycinate, aspartate, taurate and orotate.

Natural Calm magnesium is an organic magnesium salt. Combining magnesium carbonate with citric acid produces magnesium citrate when dissolved in liquid.

It’s true that different forms of magnesium behave differently in the body, but you’d be surprised at the gap between what’s proven and what’s claimed.

How Magnesium is Absorbed: Creative Marketing vs. Facts

Let’s start with the closest to incontestable truths available.

We know that magnesium supplements are first dissolved in the gastric fluid of the stomach.

The dissolved magnesium becomes ‘ionic’, which is the form that can be absorbed in the small intestine.[2],[3]

The magnesium ions then enter the bloodstream for transport to tissues and organs across the body.

Now, this is where many marketers are getting very creative. You’ll hear a wide range of science-sounding ideas about what happens to the magnesium molecule in the intestine.

Some companies are claiming that only magnesium glycinate can effectively pass through the intestine to the bloodstream. This is smart marketing, but is it science?

It’s not.

These claims are not backed with research from peer-reviewed journals. They’re not proven science. When Dr. Powers scoured the science for the source of their claims, no studies were found.

Here’s What the Science Does Say About Absorption

We can all speculate about what makes one form of magnesium more effective at passing through the intestine into the bloodstream. We can claim that amino acids help, or that tiny unicorns are needed to chauffeur the magnesium into the bloodstream.

Researchers believe that ‘solubility’ is what matters for absorption. Magnesium supplements that dissolve well are more effectively taken up in the intestine.[4]

We know that stomach acid helps with solubility; it keeps the magnesium broken down. But as the magnesium progresses through the small intestine, that acidity drops.

Some forms of magnesium may become less soluble as acidity drops in the intestine. Magnesium citrate is proven to stay soluble during this journey, which means those ions are available for uptake throughout the intestine. Researchers believe this is one reason magnesium citrate is more absorbable than inorganic magnesium salts.[10],[11]

Yes, we’ve backed that up with data.

(Update September 22, 2017: Want more data? Now you can review the results from a NEW double-blind study comparing Natural Calm magnesium absorbability with other leading magnesium brands – including CanPrev.)

Organic Vs. Inorganic Magnesium Salts

Organic magnesium salts, like magnesium citrate, are generally more soluble than inorganic magnesium salts.[4],[5],[6],[7] Numerous in vitro studies have demonstrated the superior absorption of organic magnesium salts, including magnesium citrate, in comparison with inorganic salts.[7]

Research proves that magnesium citrate:

  • produces a direct increase in blood plasma levels[8]
  • is readily ‘bioavailable’.[9] (In other words, available for use in the body.)

Organic Magnesium Salts Vs. Amino Acid Chelates

What about magnesium amino acid chelates, like glycinate or bisglycinate?

Despite some marketing claims, there is no published research to suggest these forms are more absorbable than organic magnesium salts.

Seriously. None.

The sources for claims that magnesium glycinate is better absorbed are either non-existent or not peer-reviewed. In other words, the claims are backed with no science or with opinions.

We prefer data.

Here’s what the research does say about citrate vs. glycinate:

  • One study comparing magnesium bisglycinate with magnesium oxide (an inorganic form of magnesium) found little difference in absorbability.[12]
  • A detailed review ranked citrate and glycinate in the same category, as equally absorbable forms of magnesium.[13]
  • One well-designed study showed that compared to a magnesium chelate (remember, magnesium glycinate is in that chelate category), only magnesium citrate supplementation increased blood plasma and salivary levels of magnesium.[14]

The conclusion?

The available clinical research indicates that magnesium citrate is on par with or more absorbable than magnesium glycinate or bisglycinate.

Don’t Keep Calm About Fake Science

We like to play nice and be friendly. But sometimes we have to speak up. You, as consumers, deserve better than fake science.

Here’s a funny story. A natural health practitioner we know once wrote into CanPrev to ask them for the source of their claims that glycinate is more absorbable than citrate. From their claims, you would think they were swimming in robust science.

But, no.

Cecilia Ho, ND from CanPrev wrote back saying, “There currently is no research that directly compares magnesium bisglycinate and magnesium citrate per se.”[15]

So, there you have it. “No research.”

Listen, we all make mistakes in understanding science. There’s a lot that is currently unknown. If you ever have questions about our interpretation of the science, we’re committed to getting to the bottom of it in a transparent way.

Let’s stand up for science in marketing!

Interested in learning more about magnesium glycinate vs. magnesium citrate? Read our post on What You Need to Know About Magnesium Glycinate.



[2] Coudray et al. (2005). Magnesium Res  18(4): 215-23

[3] Ranade and Somberg (2001). Am J Therapeutics 8: 345-357

[4] Siebrecht, S. (2013). Journal International de la medicine orthomoleculaire et analgogue 144

[5] Lindberg et al. (1990).  J Amer Col of Nutrition, 9(1): 48-55

[6] Firoz and Graber (2001). Magnesium Research 14(4): 257-262

[7] Coudray et al. (2005) Magnesium Research 18(4): 215-23

[8] Wilimzig et al. (1996). Euro J Clin Pharmacol 49: 317-323

[9] Ranade and Somberg (2001). Am J Ther 8: 345-357

[10] Couday et al. (2005) Magnesium Res 18(4):215-23

[11] Lindberg et al. (1990) J Amer Col Nutr 9(1): 48-55

[12] Schuette et al. (1994) J Parenter Enteral Nutr 18: 430-435

[13] Ranade and Somberg (2001). Am J Ther 8: 345-357

[14] Walker et al. (2003) Magnes Res 6(3): 183-91

[15] Ho, Cecilia, ND. Personal electronic correspondence. Dated August 3, 2016.


Anna O'Byrne

Anna O'Byrne manages the social media, writes web content and runs digital marketing for TOP Nutritionals two brands: Natural Calm Canada and SuperLeaf™ Moringa. You can read her on our other site, at