Supplement manufacturer NOW has tested a suite of popular creatine gummies and found that almost half of them failed to meet label claim for creatine content, and some of them showed detectable levels of a breakdown product, raising stability concerns. 

NOW, which is based in Bloomingdale, Ill., has tested many different sets of products over the years, like berberine and astaxanthin. In other installments of the program, the focus has been on lesser-known brands selling products in given categories on either Amazon or Walmart.com. 

In this case, the focus was on gummies featuring a particular hero ingredient: creatine. The gummies were purchased on Amazon or direct from companies’ websites. 

Popular muscle building ingredient 

Creatine is a legacy ingredient with a long history of use.  According to the Mayo Clinic, “people take creatine orally to improve athletic performance and increase muscle mass.” 

“People also use oral creatine to treat certain brain disorders, neuromuscular conditions, congestive heart failure and other conditions,” the medical authority added. 

Creatine, a popular ingredient experiencing 65% growth on Amazon in the last year, plays a role in the ATP cycle within the cell. The most common form found in dietary supplements is creatine monohydrate, which is also by far the most common form used in sports performance studies and research on other endpoints. 

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Almost all the gummies tested by NOW claimed to feature creatine monohydrate. Only one featured a different form, which is a patented creatine HCl form. 

NOW found that seven of the 12 gummies tested met label claim and displayed significant overages. Six of those seven products claimed a 5-milligram (mg) dosage, divided into four or five gummies, depending on the manufacturer. The seventh claimed a 3.6-mg dosage, divided into three gummies. 

Little to no creatine found in five products 

The five remaining products, however, contained little to no creatine content, based on NOW’s tests. In addition, all the failing products displayed small to significant amounts of creatinine, which is a breakdown product of creatine. Creatinine can be found in the body part of the natural creatine cycle but seeing creatinine in a finished good raises additional quality control concerns, NOW said. 

NOW Senior Director of Quality Katie Banaszewski said gummies can be a challenging delivery vehicle, and it was impressive to see that some manufacturers appeared to have mastered creatine delivery in this form. 

Banaszewski also commented on others that showed little to no creatine content while also displaying signs of creatine degradation. 

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“Due to the nature of gummy manufacturing, there is a possibility that creatine in gummy formulations may have degraded to creatinine during manufacturing,” she said. “Additionally, the instability of creatine in liquid formulations could be a factor contributing to the observed degradation as a result of reduced shelf life. However, it is difficult to say which contributes the most degradation based on one data point.” 

Over the course of the testing program, NOW has worked with several trusted lab partners to provide a third-party to help verify its results. That didn’t happen here, as NOW found that gummy testing capabilities are difficult to find in the market. 

“We were surprised that none of the third-party labs we typically use – which we consider the best – said they were able to test these gummies,” said Banaszewski. “Given the rapid growth of that delivery system and the regulatory requirement to confirm label compliance, the industry needs to find a solution to this dearth of testing capacity.”  

Natural Products Insider sought comment from all the failing companies for which contact information could be found. None responded in time for publication. 

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