Gluten. There is wave of gluten avoidance sweeping around the modern world. 22% of Americans currently follow a gluten-free diet, compared to 15% in 2013. In 2014, consumers spent $8.8 billion on gluten-free products — an increase of 63% from 2012
So what is gluten? Gluten is a mix of two proteins (gliadin + glutenin) found in the Triticeae family of grains including wheat, barley and rye.
Alpha-gliadin is the problematic part of gluten, and we know have a pretty good idea why this is. There are now two well defined medical conditions where gluten avoidance is a medical necessity. These are celiac disease (CD) and non-celiac gluten sensitivity (NCGS). Whether or not you have true celiac disease CD or NCGS, there are some very good reasons to avoid gluten.
What is Celiac Disease?
CD is actually an autoimmune disease (AID) triggers by gluten where our immune system is tricked into attacking the cells that line our intestines. CD is unusual for several reasons. CD is the only autoimmune disease where specific genetic markers are found in >95% of patients. The target of CD, is a human enzyme called transglutaminase (TTG). The trigger for CD (gluten) is known, and avoidance of the singular trigger causes a complete resolution of the autoimmune process.
The autoimmune process of CD causes a destruction of the cells lining our intestines. At a microscopic level, healthy intestines are highly convoluted with two layers of rippling that yield a massive surface area. The effect of this cell death in CD is to dramatically reduce the surface area of our intestines and cause malabsorption of all nutrients. The traditional gold standard for diagnosing CD is to do a gut biopsy and look at it for this intestinal flattening.
IgA antibodies to tissue transglutaminase (TTG) is a laboratory test that can detect the CD. This marker is faulty because CD often decreases the production of IgA itself. For this reason, it is a good idea to also order a total IgA test. If TTG is normal and IgA is not low, then the chance that the patient has CD is low, but not zero. These two tests are the most cost effective way to diagnose CD (~$40). Deaminated-gliadin IgG antibodies is another lab marker that can detect CD one step further the metabolic line in patients that have decreased total IgA.
Non celiac gluten sensitivity (NCGS) is reaction to ingestion of gluten-containing grains in which both allergic and autoimmune mechanisms have been ruled out. It is not an autoimmune disease, and causes a wide variety of symptoms, most commonly: bloating, abdominal pain, loose stools, fatigue and “brain fog”.
NCGS symptoms widely overlap with irritable bowel syndrome IBS: This plus the absence of a good laboratory marker, makes NCGS very difficult to diagnose. Thankfully the treatment (avoiding gluten containing foods) is free.
Most patients diagnosed with CD are older children or adults. The most common signs and symptoms span the entire body and include: Dermatitis Herpetiformis, Dental enamel hypoplasia of permanent teeth, Iron-deficient anemia resistant to oral Fe, Osteopenia/Osteoporosis, Short Stature, Delayed Puberty, Hepatitis, Arthritis, Epilepsy (with occipital calcifications).
We used to think that genetics and a diet with gluten alone would cause celiac, but that is clearly not the case. You can have the genetic markers (HLA-DQ2 or -DQ8) and eat lots of wheat and never develop celiac. Some people with the celiac risk genetics eat wheat all their lives and only develop CD at age 70. From this we know that there must be more to causing CD than genes and gluten alone.
We now know that three other factors are key to developing CD: Increased gut permeability (“leaky gut”), an immune response (inflammation and antibody production), and an altered gut microbiome.