Tuesday, 23 August 2016

Still think gluten sensitivity isn’t real?

wheat

While the scientific community has widely accepted celiac disease as a condition caused by gluten and other related proteins, non-celiac gluten sensitivity has remained a topic of heated debate in the media and among the general public. In this article, I’ll talk about the reasons I have acknowledged non-celiac wheat sensitivity as a real condition for many years, and I’ll describe the results of a new research study performed at Columbia University that adds supportive evidence. Before we jump in, though, let’s review the difference between celiac disease and non-celiac wheat/gluten sensitivity.

Celiac disease vs. non-celiac wheat sensitivity

Celiac disease and non-celiac wheat sensitivity are two distinct conditions, with a few major differences. Celiac disease (CD) is an autoimmune disease characterized by an inflammatory immune response to wheat gluten, rye, barley, and related proteins. It results in marked disruption of normal gut tissue structure, including atrophy of epithelial cell projections called villi and an enlargement of intestinal crypts where new epithelial cells form from stem cells. CD is strongly associated with the haplotypes DQ2 and DQ8 of the HLA gene (1). In terms of blood markers, transglutaminase 2 (TG2) autoantibody is considered the most sensitive marker for celiac disease (2). Non-celiac wheat sensitivity (NCWS, and also called non-celiac gluten sensitivity) is a term applied to individuals who experience symptoms in response to wheat or gluten ingestion but lack the characteristic markers of celiac disease. Symptoms can range from GI discomfort to fatigue and other neurological issues. These people tend to improve on a gluten-free diet (3). Unfortunately, many are mocked or ridiculed for avoiding wheat and told that their sensitivity is “all in their head.”
New research says there is such a thing as gluten sensitivity.

Wheat sensitivity: Is it all in your head?

In response to continued suggestion by the media and some of the medical community that wheat sensitivity is merely psychological, I have written extensively on my blog in support of NCWS as a real condition. For one thing, a variety of different proteins in wheat can elicit an immune response beyond gluten. NCWS might even be more serious than celiac disease, as many people who test negative for celiac disease continue to eat wheat and put themselves at serious risk for developing autoimmunity. Gluten free is not a fad, and self-reported NCWS has been associated with a wide variety of disorders in epidemiological studies. Those who claim that gluten sensitivity isn’t real often cite this study, attributing any negative reactions to gluten to FODMAPS. However, as I addressed in a previous article, the researchers chose whey protein for their control group, a pretty poor choice considering that many of their subjects likely had inflamed guts and multiple food sensitivities. The evidence, both on paper and from my own clinical experience, clearly points to the existence of NCWS.

The latest research study

Still not convinced? In a recent study, researchers at Columbia University Medical Center sought to obtain objective evidence to determine if NCWS is real (4). They enrolled 80 individuals with self-reported non-celiac wheat sensitivity (NCWS), 40 individuals with celiac disease, and 40 healthy subjects for the study. NCWS patients were excluded if they showed any of the characteristic diagnostic markers of celiac disease (celiac-specific IgA, anti-TG2 autoantibody, or celiac-like histology). The researchers took blood samples and intestinal biopsies from all 160 patients. The blood samples were used to look for particular signaling molecules and proteins in the blood, while the biopsies were used for histological analysis of the tissue microstructure. In addition to comparing these measures between conditions, they also took a subset of 20 NCWS patients who had adhered to a gluten-free diet for six months and compared their blood and biopsy samples before and after gluten avoidance.

Gluten-sensitive individuals have leaky gut

So what did they find? Non-celiac wheat sensitive individuals have … drumroll … leaky gut! NCWS subjects showed increased intestinal permeability compared to healthy subjects. This is not really all that surprising, since we know that gliadin, a component of gluten, can affect tight junction proteins (5). In addition, subjects in the NCWS group had systemic immune activation. Serum levels of both lipopolysaccharide-binding protein (LBP) and sCD14 were significantly elevated in individuals with NCWS in comparison with individuals with celiac disease and healthy controls. These are sensitive markers of microbial translocation. In other words, they indicate that bacteria and other microbes from the gut interior are “leaking” into the bloodstream, inducing a low-grade, chronic inflammatory response from the immune system (6). Histological analysis of biopsy tissues showed that the NCWS group also had epithelial cell damage similar to the celiac disease group, a result supported by elevated levels of serum marker FABP2 (7). Moreover, in the subset of NCWS individuals analyzed before and after adherence to a gluten-free diet, they found that inflammation and cell damage markers improved significantly after six months of gluten avoidance.

Gluten sensitivity exists—here’s how to know if you might have it

Evidently, there are certain individuals who possess non-celiac wheat sensitivity and would benefit greatly from avoiding wheat. It’s unfortunate that so many people who might benefit from a gluten-free diet never try it or don’t stick with it because of the lack of support from media, the medical community, and the general populace. I hope that this new research study (and others that will surely follow) will make it just a bit easier for people to make the right choice for their health. So how can you know if you have NCWS? The biological markers used in this particular study may be used in the future to help diagnose NCWS, but at the moment, they are purely used for research purposes. Nevertheless, there are two ways to determine your gluten tolerance:
  • A Cyrex panel: Cyrex Array 3 is a panel that tests your potential for wheat and gluten protein reactivity and autoimmunity. It must be ordered by a healthcare practitioner.
  • A self-experiment: Eliminate gluten from your diet for 60 days and then perform a gluten challenge, taking careful note of any symptoms. I still hold that this is the best way to determine your tolerance for gluten.
Now I’d like to hear from you. Did this article change your perception of gluten sensitivity? Do you or someone you know have non-celiac wheat sensitivity? Have you ever tried a gluten challenge? Share your opinion in the comments!

from Chris Kresser http://chriskresser.com/still-think-gluten-sensitivity-isnt-real/
via Holistic Clients

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