Do “gluten-digesting” pills work?

“Helps digest gluten and carbs,” reads the label of me+my Gluten Assist. Really?

Breaking down gluten

“Gluten is a really tough plant protein,” notes Daniel Leffler, director of clinical research at the Celiac Center at Beth Israel Deaconess Medical Center in Boston. “A variety of enzymes in the stomach are responsible for chopping up proteins, but they don’t work on gluten.”

That allows long fragments of undigested gluten to leave the stomach and enter the small intestine. Most people can tolerate those fragments. But not those with celiac disease.

“Their immune system mistakes gluten for a dangerous foreign protein, and attacks it the way it would attack bacteria or a virus,” explains Leffler. “That damages the intestine, and causes abdominal pain and diarrhea and so on.”

The only option for people with celiac: a lifetime of avoiding gluten…if they can.

“We think that a lot of people with celiac disease never fully heal,” says Leffler. “It’s not that they aren’t doing their very best to be as gluten-free as can be. It’s just that there’s no such thing as being completely gluten-free in our environment because foods, particularly restaurant foods, are often contaminated by small amounts of gluten.”

Enjoy gluten with the help of a pill?

Researchers are looking for an enzyme that can break down the small amounts of gluten that people with celiac disease are inevitably exposed to. “While it has to be able to snip gluten in a test tube,” says Leffler, “it also has to digest gluten in the stomach in the presence of acid and other foods. And it has to digest gluten quickly, before it can leave the stomach and enter the small intestine. It’s a very high bar.”

High, indeed. In an industry-funded study, five “gluten-digesting” supplements—they went unnamed—couldn’t even pass the test-tube snip test.

What about brands that add Tolerase G, an enzyme that seemed promising in test tubes and in people without celiac disease? The only study in people with celiac was useless because study participants had no symptoms after taking either Tolerase G or a placebo.

Of course, weak evidence hasn’t stopped supplements from using names—like Gluten Assist, Gluten Cutter, Gluten Rid, Gluten Digest, GlutnGo, Gluten Block, or Gluten Free-er—that sound like they help.

“I worry that they provide a false sense of security,” says Leffler. “People who take them may think they can be less careful with their diet, and that can do significant harm in the long run.”

But Leffler, who is working with a company on a new enzyme, is optimistic. “The idea makes so much sense therapeutically,” he notes. “The right enzyme and the right formulation could be effective.”

Just don’t expect to find that right enzyme and right formulation on your drugstore shelves anytime soon.

Bottom Line

“There’s no good evidence that the currently available enzymes can protect people with celiac disease from even small amounts of gluten,” says Leffler.

Photo: thodonal/

The information in this post first appeared in the April 2017 issue of Nutrition Action Healthletter.

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7 Replies to “Do “gluten-digesting” pills work?”

  1. I understand that only about 1% of all people have celiac disease and must avoid gluten. Is there any benefit in avoiding it for the rest of us?

    1. Thanks for your question, Fred! The recommendation from leading celiac disease experts is that people without celiac disease don’t need to avoid gluten. There’s no benefit in doing so.

  2. I don’t have celiac, but I do have a gluten sensitivity. I get a bad stomach ache if I eat gluten. I have found that a couple of the “gluten clippers” do work for me. I can have an occasional small glutenous cookie or other item without the stomach ache if I take one of those pills first. Apparently it breaks down the gluten enough for my system.

    1. Studies have shown that a high percentage of people who think they have non-celiac gluten-sensitivity are actually sensitive to FODMAPs (Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols) and not to gluten itself.

      1. Carol, the diet can be difficult. Not all foods that contain FODMAPs will necessarily be problematic. My understanding is that an elimination diet is needed to ascertain which food(s) cause you symptoms.

        Your best bet is to talk to a dietitian, either directly or via your doctor, for guidance.

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