Over the past decade, legions of men have given gluten the boot. Aside from those who've given it up because they were diagnosed with celiac disease (meaning this protein found in wheat and other grains provokes a harmful autoimmune response) or for no other reason other than "everybody's doing it," only an estimated 6 percent of Americans should be going gluten-free because of a non-celiac gluten sensitivity (NCGS). For these people, ingesting gluten doesn't do serious intestinal damage, but it can cause major stomach upset, bloating, diarrhea, joint aches, fatigue, and more.

Or so doctors thought. Groundbreaking new research questions whether the condition is real, or if it likely affects far fewer people.

The study in question is from one of the world's top gastroenterology researchers, Peter Gibson of Monash University in Australia. It was Gibson's past research that helped put NCGS on the map as an actual condition, but a few years back, he began questioning whether it is actually gluten or something else entirely that causes so many people so much gastrointestinal distress. So Gibson went back to the drawing board. For his new study, he rounded up people who did not have celiac disease but believed they had NCGS. He cycled them through a series of diets over several weeks without them knowing which was which. But this time, rather than focusing solely on gluten, Gibson separated out all potentially problematic ingredients, including lactose, specific preservatives, and FODMAPs, a class of carbohydrates found in a variety of foods. He wanted to determine if one of these, rather than gluten, was responsible for the participants' symptoms.

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Sure enough, the study revealed that FODMAPs, not gluten, was the likely cause of bloating, gas, and other unwanted effects normally ascribed to gluten. In fact, Gibson found no evidence that gluten had any impact at all. Since this study examined only 37 people, much more research must be done on larger sample groups to confirm these findings and to determine whether gluten may indeed cause problems for some people beyond this small group – or if NCGS really isn't legit. 

Still, the study is making waves. "This is a monumental study," says Dr. KT Park, a gastroenterologist at Stanford University School of Medicine. "It's the first of its kind to generate this type of prospective data specific to NCGS."

The Villain: FODMAPs or Gluten?
Even if this study is found to be true, the diet recommended may not look much different than a gluten-free diet. According to Gibson, the misunderstanding stems from the fact that many of the same foods that contain gluten are also high in FODMAPs. "The two co-exist in wheat and rye," he says. "People who eliminate gluten from their diets are also reducing their FODMAP intake–and this may be sufficient to improve their gut symptoms. It was not until we separated FODMAPs from gluten, and then re-challenged people in the study with a diet that contained gluten but was free of FODMAPs, that we were able to show that it's not the gluten in wheat that's the culprit for many people."

But FODMAPs are found in more foods than just grains. "They're also in onions, garlic, apples, pears, legumes, stone fruits, mushrooms, and much more," says Gibson. Therefore, given their prevalence in a range of foods, FODMAPs could be the hidden cause of many people's GI issues.

Still, Park believes it's too early to put NCGS on the chopping block. "Do I think NCGS is over-reported and overemphasized? Absolutely," he says. "But do I still think the possibility exists of a true entity caused NCGS? Absolutely. The problem is that, at the moment, NCGS is the most common diagnosis after seemingly everything else has been ruled out. But there's a huge grey area between NCGS, irritable bowel syndrome, and other issues. Gastroenterologists have the impossible task of trying to differentiate between them in patients."

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The Problem With Gluten Elimination for the Gut 
But getting to bottom of your issue is crucial. According to Park, when you constantly consume a substance your system is sensitive to, whether it's gluten or FODMAPs, you mess up the balance of good and bad bacteria in your digestive tract, which can negatively impact your overall health. Therefore, you want to make sure you're avoiding–and not avoiding–the correct foods. 

You especially don't want to eliminate healthy gluten-containing foods when you don't really need to, because whole grains provide much-needed fiber and are nutrient rich. "We want this research to discourage people from going gluten-free unnecessarily," Gibson says. He adds that, "it is more challenging to eat a nutritionally complete diet if you eliminate gluten, it's more expensive to eat gluten-free, and it makes it difficult to eat at restaurants. If you suspect gluten is causing gut symptoms, it's essential that you get checked for celiac disease."

The New Recommendation: Starting With FODMAPs
But if your celiac test comes back negative, Gibson suggests cutting back on FODMAPs before axing gluten. "You're better off trying a low FODMAP diet first," he says. "It will have a 70 percent chance of a very good effect. We do not know what chance a gluten-free diet has, but it often only partially helps, because gluten isn't usually the main problem."

Park also recommends the low-FODMAP diet. "When patients come to me with GI symptoms, and they don't have celiac, I do not tell them to ditch gluten," he says. "Instead, I give them a handout explaining a low-FODMAP diet. I also tell them to eat a quarter- or half-cup of Greek yogurt, one without added sugars or other additives, every morning to help balance gut bacteria and support digestion."