Poor old wheat seems to be copping a hard time in the media at the moment all because it contains gluten. Gluten seems to have been demonised for every health condition under the sun in recent years, with the least attention paid to the condition it actually affects, celiac disease.
To make sense of the science around wheat, we need to sort the “wheat from the chaff” so to speak. To do this I am going to summarise two recently published scientific papers – one about NCGS (non-celiac gluten sensitivity) and one about NCWS (non-celiac wheat sensitivity).
Non-celiac “sensitivity” to gluten is described by Umberto Volta and colleagues as a “work-in-progress entity in the spectrum of wheat-related disorders” that affects less than 1% of individuals. Non-celiac gluten sensitivity is triggered by gluten in people without celiac disease or wheat allergy. The proposed mechanism for gluten causing symptoms involves the immune system. Most of the reported symptoms are gastrointestinal and overlap substantially with IBS. Because most of the research into NCGS happened prior to the evidence based FODMAP dietary approach to IBS management, it is impossible to determine whether the symptoms were caused by gluten or FODMAPs in much of the existing research. New research is needed to determine if other reported symptoms, particularly neurological ones like “foggy brain” might be related to gluten, or not.
No blood marker for NCGS is available, but half of sufferers test positive for coeliac IgG anti-gliadin antibodies, which disappear quickly after gluten-free diet. All this makes me wonder if NCGS exists in its own right or if people suffering the symptoms either suffer from IBS, or are “at risk” of celiac disease or maybe both?
A recent paper by Schuppan et al (2015) starts out by stating that non allergy-non-celiac wheat sensitivity (NCWS) has become a common and often overrated diagnosis. Skepticism mainly relates to those reporting gastro-intestinal symptoms in the absence of general or intestinal signs of inflammation. Such symptoms are invariably attributable to IBS-related intolerance to FODMAPs, rather than allergy to wheat.
Non-celiac wheat sensitivity is an immune reaction to wheat whereby sufferers present with symptoms such as worsening of an underlying inflammatory disease soon after eating wheat. Wheat amylase-trypsin inhibitors (ATIs) have been identified as the most likely triggers of NCWS. Wheat ATIs are a family of up to 17 similar proteins that represent 2–4% of the wheat protein. When wheat is consumed they activate immune-mediated responses within and outside the gastro-intestinal tract.
So, long story made short, if you suffer from a “foggy brain” or other nervous system responses to eating wheat or have tested positive to celiac IgG anti-gliadin antibodies, then we might be looking at NCGS. If you have an underlying inflammatory or autoimmune condition and react to wheat, NCWS might be the answer. For the vast majority of people who burp and bloat and get windy after eating wheat, the most likely cause is IBS.