As one of the most sought after gut health experts in the world, Mahmoud A. Ghannoum, PhD—who actually is the one who coined the term “microbiome“—looks at bacteria essentially all day, every day. Through his probiotic and gut health kit company Biohm, Dr. Ghannoum has collected thousands of samples from customers who are looking to find out exactly why they’re experiencing gut issues, and how they can tweak their diets to live their healthiest lives.

Recently, Dr. Ghannoum has noticed many “healthy” women were experiencing digestive problems. These were women who worked out regularly, bought organic food, and made an effort to cook nutritious meals. Yet his data showed many were low in prebiotics, which work alongside probiotics to keep the gut balanced. “Studying the data, I realized what they had in common was that they had cut gluten from their diets, and that led to them not getting enough prebiotics,” Dr. Ghannoum says.

So does this mean gluten is…good? Here, Dr. Ghannoum and another gut expert who regularly advises his patients to eliminate gluten give an in-depth look at exactly how cutting ties with the protein family affects the microbiome.

Keep reading to find out how cutting gluten affects the gut.

The gluten-fiber connection

“Unless someone has celiac disease, a gluten allergy, or sensitivity, I do not recommend people cut gluten from their diet,” Dr. Ghannoum says. He explains that wheat is high in inulin, a prebiotic fiber. “Multiple studies have shown that inulin supports the good bacteria and fungi in the gut,” he says. “Studies have also shown that people who are low in inulin have an increase in the bad bacteria in the gut, such as e. coli.”

According to Dr. Ghannoum, not getting enough inulin—that oh-so-helpful fibrous prebiotic—can lead to some pretty unpleasant side effects, like bloating, constipation, and diarrhea. (Hey, you were warned it wasn’t pleasant.) “Because of these findings, I recommend people have a moderate intake of wheat foods, unless they have celiac disease, a gluten allergy, or sensitivity,” he says.

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But gut doctor and Happy Gut author Vincent Pedre, MD, disagrees. “I have not seen this issue,” he says. “Most of the time, cutting gluten actually improves gut function because gluten increases the permeability of the gut, regardless of whether you are sensitive to it or not.”

The disparity can be enough to make you want to cry into your pasta bowl, but the doctors do agree on the same course of action: Try cutting out gluten and notice if you feel better or worse. If you feel better, keep it up. If you don’t notice a change or feel worse, add it back in.

How to get enough prebiotics while living a gluten-free life

If you do decide to cut out gluten, Dr. Pedre and Dr. Ghannoum offer up the same advice: Increase your fruit and veggie consumption and start taking a probiotic or prebiotic. (Pro tip: Look for one with inulin since that’s what you’re aiming to get more of.) “There are many ways to get prebiotics in the diet, [including] garlic, onions, dandelion greens, and blueberries,” Dr. Pedre says, adding that most people are only getting 10 grams of fiber a day when you really should aim for between 25 and 35.

Both experts say that if you’re not used to eating a lot of fiber, it’s important to add it in slowly so as not to overwhelm your digestive system, which, again, can lead to bloating. “Take small steps to increase it and spread it out throughout the day,” Dr. Ghannoum says.

When it comes to cracking your microbiome’s code, it almost always involves a bit of trial and error. The key isn’t to just automatically take anything with gluten off the table. It’s learning what works for your body and what makes you feel the best.

There’s another downside to going gluten-free. But if you are uber-sensitive to gluten, be careful—it could be in your beauty products.