According to Now, most of the brands tested failed to include the chelated magnesium form stated on the label.
Now’s (Bloomingdale, IL) latest round of testing products from lesser-known supplement brands purchased on Amazon reveals misleading and inaccurate labeling of Magnesium Glycinate products. According to Now, most of the brands tested failed to include the chelated magnesium form stated on the label. Chelated forms of magnesium such as magnesium bisglycinate or glycinate offer high levels of water solubility and lack a laxative effects, as well as superior absorption. However, the chelates are more expensive and therefore at risk for substitution with lower quality materials such as magnesium oxide and magnesium carbonate, simply blended with glycine.
Now purchased 16 magnesium glycinate products, including two of its own, on Amazon and tested them in two facilities: its own in-house lab and the Eurofins contract laboratory. Magnesium content was tested using Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES), and levels of water-soluble magnesium glycinate were determined by using the same ICP-OES technology, but by applying a gentle water extract instead of acid digestion to the samples.
Results showed that 12 out of the 16 products met label claims when tested for total magnesium content, but only Now’s products met the label claim when testing for chelated forms of magnesium. This suggests that the other brands are using non-soluble forms of magnesium in place of chelated forms.
“Unfortunately, it is known in the industry that many brands either knowingly or unknowingly simply blend glycine with magnesium oxide or carbonate and then label the product as ‘Magnesium Glycinate,’” said Dan Richard, Now’s vice president of global sales and marketing, in a press release. “The difference is that the improperly labeled product is much lower in cost and is not a fully reacted or bonded chelate.”
The test results also found that some brands may be intentionally mislabeling their products in order to get high potency claims, which one brand claiming 750 mg of Magnesium Glycinate per capsule when legal labeling should in fact list the elemental dose of magnesium and not the total weight of a RDI ingredient.
“It’s disheartening to see consumers misled and cheated when they buy products on Amazon, over and over again,” Richard added. “This should matter to everyone in our industry; consumers may grow to distrust the entire supplements industry when not getting the benefits they expected and deserved. And companies that work hard to do things right are losing sales to these bad actors.”
Read full breakdown of results here.