Headlines are, once again, making bold statements based on a recent study conducted in England, such as the headlines from the Science 2.0 website: “Double-Blind Randomized Placebo Trial Shows Gluten Has No Effect.”
Is this true?
Let’s take a look at the study. 28 participants were chosen on the basis of having no known intolerance to gluten, wheat, or grains, i.e., eating a conventional diet without gastrointestinal symptoms. All were instructed on how to follow a gluten-free diet. Half (14) were given sachets containing gluten (14 grams), the other half (14) were given gluten-free sachets for two weeks to add to food. At the end of the two week period, both groups were assessed for gastrointestinal symptoms such as abdominal pain, reflux, constipation, diarrhea, etc. No differences in the gluten-consuming versus the gluten-free groups were observed. Conclusion: Gluten avoidance is unnecessary for people without celiac disease.
Those of you who have been following the Wheat Belly conversation likely already see all the “holes” in this study—there are many. First of all, if you choose participants who consume an unrestricted diet and have no abdominal symptoms, it is no surprise that essentially continuing to consume gluten should result in no change. In other words, by screening people for not having gluten intolerance, they introduced bias into the participant selection process.
Beyond this, there are other issues:
- We know that gliadin (within gluten) is the initiating event in many, if not most, autoimmune diseases. But this is a process that requires months to years to develop and cannot be observed in the 2 weeks of this study. Triggering of autoimmunity does not require celiac disease nor genetic celiac predisposition to be present. The increased intestinal permeability initiated by gliadin occurs in the majority of people.
- Gliadin-derived opioid peptides serve as appetite stimulants whether or not you have a celiac predisposition. This, of course, was not assessed.
- Because purified gluten was administered, there was no wheat germ agglutinin, the potent lectin gastrointestinal toxin and disrupter of digestion.
- Purified gluten lacks the amylopectin A of wheat and grains, the super-carbohydrate responsible for the extravagant blood sugar-raising potential of gluten-containing grains. It’s also amylopectin A that triggers insulin and, over time, generates insulin resistance, the process that underlies type 2 diabetes and weight gain.
- Purified gluten contains no phytates that block absorption of magnesium, calcium, iron, and zinc.
- There are no alpha-amylase inhibitors, thioreductases, and many other proteins that trigger allergic responses.
In other words, administered purified gluten to a small number of people screened for no overt intolerance to grains over a short period proves nothing.
One of the great disappointments in this study is that one of the researchers behind the study was Dr. M. Hadjivassiliou who has pioneered studies that have connected a specific form of gliadin protein within gluten with several neurological disorders, especially cerebellar ataxia and idiopathic peripheral neuropathy. Hadjivassiliou, for instance, demonstrated that half of all people who have idiopathic (without known cause) peripheral neuropathy and lose, for instance, all sensation to their legs, have antibodies against gliadin and the majority improve over time with gliadin (gluten) avoidance. Why he would participate in such a flawed study as the one above is beyond me.
This silly study therefore adds nothing to our wisdom on diet and health, but does illustrate how far people are willing to go to defend the role of wheat and grains in diet.