New Research on Gluten Sensitivity
Gluten sensitivity has been a hot topic for a couple of years now. If you haven’t personally experimented with a gluten free diet, I’m sure you know someone who has. At the very least, you’ve seen Jimmy Kimmel make fun of people for avoiding gluten while being unaware of what it is.
Arguably, because it is in the public eye to the degree that it is, it has become trendy and many people are self-diagnosing non-celiac gluten sensitivity with little or no evidence. Of course, as with all health trends, there has been a certain amount of skepticism that gluten sensitivity is as wide-spread as it seems or that it even exists at all.
Unfortunately there has been little research to answer these questions. There has been some speculation and limited evidence that there is no such thing as non-celiac gluten sensitivity. A new study refutes those claims.
A in the added to this discussion. The study was performed using the gold standard of scientific inquiry, a randomized, double-blind, placebo-controlled, cross-over design. This is rare in nutritional research and gives the results a little more weight.
61 participants who self-identified as being gluten sensitive were randomly assigned into two groups. All participants were eating a gluten containing diet for 2 months prior to the start of the study. Both groups were assigned a gluten-free diet that lasted 5 weeks. During week two, one group was given 4.375g (about the amount found in two slices of white bread) of gluten and the other was given the same amount of rice starch. The thing that makes this a double-blind study is that neither the participants or the researchers knew which group was getting what until after the study was over. In week three, the groups were switched. The gluten group was given rice starch and vice versa. During weeks 4 and 5 both groups stopped taking the pills and just ate their gluten-free diets. Every day, each of the participants self-reported their experience with a battery of gluten associated symptoms including 15 intestinal and 13 extra intestinal. Fifty nine participants finished the trial
At the end of the trial, the authors found a statistically significant (p = 0.034) difference between the gluten and placebo (rice) treatments.
From the study’s results:
Abdominal bloating ( P =.040) and pain ( P =.047), among the intestinal symptoms, and foggy mind ( P =.019), depression ( P =.020), and aphthous stomatitis ( P =.025), among the extra-intestinal symptoms, were significantly more severe when subjects received gluten than placebo.
Digging a little deeper into the results, we see that 31 of the participants had an equal response to gluten or placebo, 13 had no significant difference (there was a difference but it was not enough to be statistically meaningful), 5 individuals had stronger negative effects to placebo, and 9 had stronger effects to gluten.
The findings of this work are significant enough to pay attention to. It lends some much needed credibility to the gluten free movement. However, we need to keep in mind that 9/51 is roughly 15% and that comes from a group of people that all identify themselves as having a gluten sensitivity. That’s a small subset of a small subset. It cannot be well extrapolated to a population at wide.
It is important because it is the first well designed study that indicates there may be such a thing as non-celiac gluten intolerance. That is beneficial because it will hopefully lead to more studies testing a wider base of individuals.
Photo Credit: Bart Everson