First, a little background: Back in 2011, an Australian researcher named Peter Gibson conducted what would become a seminal study in the gluten-free movement. In a randomized, double-blind, and placebo-controlled study (essentially the gold standard of science), his team found that gluten caused "gastrointestinal distress" in non-celiac individuals.
But, something about the research seems to have been weighing on Gibson's mind, because he repeated the study last year in order to see just what was causing the negative reactions. This time, he controlled for as many variables as possible, only permitting subjects to eat meals provided by the research team. The researchers also made sure to remove all other conceivable digestive culprits from the equation — including dairy, preservatives, and a specific type of fermentable carbohydrates called FODMAPs.
Each of the 37 subjects were given a diet low in FODMAPs for two weeks, and were then put on the following food plans for three days: a high-gluten diet, a low-gluten regime, and a gluten-free placebo. The researchers asked the subjects to report any digestive unpleasantness over the course of the nine-day study. They found that each of the three diets elicited the same amount of subjects to report inflammation symptoms. As Gibson wrote in the study, which was published in the journal Gastroenterology, “In contrast to our first study…we could find absolutely no specific response to gluten.”
Indeed, the researchers think that FODMAPs might be the real cause behind what people think is gluten sensitivity. They found that putting the subjects on the FODMAP-free diet at the beginning of the experiment cleared up any digestive issues they had, but when they went on the three treatment diets (each of which contained FODMAPs), their symptoms returned, regardless of whether the diet contained gluten or not. Of course, there are two important caveats worth mentioning. First, this finding has nothing to do with celiac disease, which is specifically characterized by a failure to properly digest gluten itself. Second, FODMAPs tend to be found in many of the same foods as gluten — namely, bread, pasta, and other processed wheat products. So, it's unsurprising that many people have found that abstaining from those foods reduces digestive problems.
While the researchers don't rule out the reality of celiac disease, this study suggests we may have jumped the gun on gluten. Regardless, we think this finding demonstrates the vital importance of conducting nutritional studies that are precise and airtight. With all the controversial and contradictory information flying around about things like gluten, we need to be able to turn to hard science in order to truly understand how our bodies work.