A recent study performed by investigators at the Celiac Disease Center at Columbia University Medical Center (CUMC) and presented at the recent Digestive Disease Week meeting in Washington, DC, tested 22 major probiotics (the researchers have declined to name the specific brands). It found some traces of gluten in 12 of them.
"Many patients with celiac disease take dietary supplements, and probiotics are particularly popular," said first author Dr Samantha Nazareth from CUMC.
“When it comes to gluten-free compliance and the FDA, the FDA does not require certification. For the FDA, it’s about the definition which for gluten-free the agency sets at 20 ppm or less,” Jackie Bowen, NSF’s manager of gluten free certification programs, told NutraIngredients-USA.
One product fails clam
In those supplements which had gluten, the researchers found four that had more than 20 ppm. Only one of those products made a gluten-free claim.
"We know that most patients with celiac disease only develop intestinal damage when consuming more than 10 milligrams of gluten daily, and it is unlikely that contaminated probiotics can lead to that amount unless patients are ingesting mega-doses," added study co-author Dr Benjamin Lebwohl. He did question, however, why gluten could be found in any of them.
Question of excipients
Gluten could be in probiotics for several reasons. One is the kind of food the bugs are fed could contain gluten, and some traces of that might find its way through the manufacturing process. Or the excipients used to make a finished product could contain gluten. Or in a poorly controlled manufacturing environment, some cross-contamination could occur.
“Our members adhere to GMPs which are very strict about what you allow into your plants. A product could contain gluten as a result of the standardizing agents that are used. If a customer wants a different level of CFUs, say 10 million instead of 20 million, you would in effect ‘cut’ that with an excipient. It’s not like there are only bugs in the capsule,” said George Paraskevakos, executive director of the International Probiotics Association.
In a statement about the research, the IPA said that certain growth media or excipients “may introduce very small amounts of gluten. To control for this, certified production ingredients can be used or, if those are not available, products should be tested using accredited labs and methods to ensure levels remain below the ‘gluten-free’ labeling limit.”
NSF's Bowen said the key question is how excipients are handled through the manufacturing process. No one disputes that they are necessary parts of the finished product.
“Excipients serve really important functions,” Bowen said. “They can be starches that absorb water make capsules expand and disintegrate and that is an important function.”
Confirmation of what you already know
Bowen said when companies dietary supplement companies come to NSF for gluten-free certification, such as Twinlab, those companies generally already have all their ducks in a row and are seeking confirmation of something they already know to be true.
“For the most part you are going to have companies that have done their due diligence up front and want verification of that. For the most part they have got really solid quality systems set up in advance,” she said.
“If your raw materials are well defined and controlled, and your manufacturing process is well defined and controlled, you can’t help but make a high quality product. But just because you have an ingredient that you bought that was certified gluten-free, if you bring it into an environment that it not certified to exclude gluten contamination, then you can’t necessarily still trust that,” Bowen said.
For more on NutraIngredients-USA's ongoing Probiota Americas, click here.