Magnesium is hot. 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 …a lot of claims are completely unfounded.
If you scroll to the very bottom of this post, for example, you’ll read a very surprising admission from 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 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 clinical research 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.
Facts vs. Myths: The Concise Version
This is a long, intense post, so if you aren’t down with reading the whole thing, here are the Coles Notes:
- 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 by some magnesium companies.
How Magnesium is Absorbed: Creative Marketing vs. Facts
Let’s start with what seem like the incontestable truths.
We know that Magnesium supplements are first dissolved in the gastric fluid of the stomach.
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?
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 little 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.
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 in the more alkaline 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.,
Yes, we’ve backed that up with data.
Organic Vs. Inorganic Magnesium Salts
Organic magnesium salts, like magnesium citrate, are generally more soluble than inorganic magnesium salts.,,, Numerous in vitro studies have demonstrated the superior absorption of organic magnesium salts, including magnesium citrate, in comparison with inorganic salts.
Research proves that magnesium citrate:
- produces a direct increase in blood plasma levels
- is readily ‘bioavailable’. (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.
Some magnesium glycinate brands publish pseudo-science on absorbability, but you’ll notice their sources are either non-existent or not peer-reviewed. In other words, they’re backing their claims 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.
- A detailed review ranked citrate and glycinate in the same category, as equally absorbable forms of magnesium.
- 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.
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. (That is, science-sounding claims with no basis.)
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.”
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!
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