Poor gluten. It’s really had a tough couple of years, and there doesn’t seem to be any end in sight.
Approximately 1% of the worldwide population has Celiac disease which requires management with a gluten-free diet; this combined with the estimated 15-25% of North Americans choosing gluten-free products has driven the gluten-free food industry to roughly $1.5 billion in revenue.1
So do we need to be avoiding all things gluten? I routinely speak with people who have given up gluten for everything from weight loss to arthritis, yet there appears to be a knowledge gap on what it is, where it is found, and if it is in fact the big bad wolf huffing and puffing to blow our health down.
So let’s take a peek behind the gluten curtain, starting with what it is and what’s known thus far about gluten-related conditions.
Celiac Disease vs. Wheat Allergy vs. Gluten Sensitivity
Gluten is a protein contained in wheat, barley, and rye. Most think of bread, pasta, and cereals as the things to avoid when going gluten-free. But it is actually contained in a much wider variety of items – everything from beer, soy sauce, and communion wafers to medications, vitamins, and lipstick (a more inclusive list can be found here). Only recently did the Food and Drug Administration (FDA) issue a regulation standardizing the labeling of gluten-free items.
Gluten is the irritant for Celiac disease (CD), an autoimmune condition that causes damage to the intestinal lining and is genetically linked.2 Individuals with other autoimmune conditions are predisposed to develop CD and vice versa.2
Although most consider gastrointestinal symptoms (abdominal pain, diarrhea, constipation, vomiting) as the only signs of CD, it can actually effect many other body systems. Infertility, osteoporosis, neurological disturbances, and a skin condition called dermatitis herpetiformis have all also been attributed to untreated CD.
Diagnosis requires blood work and an intestinal biopsy. The only known treatment: gluten-free diet.
A wheat allergy varies in that it is an immune system response to proteins contained in wheat, not necessarily gluten. Symptoms after consuming wheat are immediate and may be gastrointestinal in nature, but more common allergy reactions include hives, watery eyes, or a dangerous swelling in the throat which could lead to anaphylaxis.
Diagnosis requires an allergy skin-test or a medically supervised food challenge with wheat. Besides treating symptoms with medications, the only option is avoidance of wheat-containing products.
Non-celiac gluten sensitivity, although identified in the 1980’s, has made a recent research comeback in gluten-related conditions. There seems to be a population of individuals where, despite being negative for all Celiac disease diagnostic tests, symptoms are eliminated when gluten is removed from the diet. These symptoms may be similar to those seen in CD but they are often non-intestinal in nature: joint pain, behavior disorders, muscle pain, or chronic fatigue.2 Although gluten has been blamed for certain conditions such as autism and schizophrenia, there has yet to be conclusive evidence that gluten is the main culprit.4 A small subset of patients seem to respond positively to a gluten-free diet but it’s not the case in many others – all indication that further research is needed in this area.4
The question arises in some, however, if it’s the elimination of gluten or some other component of wheat that changes symptoms.1,6 For example, individuals with irritable bowel syndrome (IBS), who can have similar gastrointestinal problems to those with CD, often find relief by following what is known as a low FODMAP diet. 5,6
It’s not based on the removal of gluten, but rather certain types of carbohydrates in foods which can lead to gas, bloating, diarrhea, and constipation.5 Wheat contains a type of carbohydrate called fructan which is considered a trigger in the FODMAP approach.
To complicate matters, a test for gluten sensitivity does not yet exist – diagnosis is really a matter of eliminating all other possibilities and conducting a trial of gluten removal and reintroduction to monitor the effects. Unfortunately this imperfect science can’t pinpoint gluten as the problem, nor can it explain the chain of events leading to symptoms.
Should you eliminate gluten?
Before you swear off wheat consider the following:
1. Speak to your physician before making any dietary changes if you suspect CD. If you eliminate gluten prior to testing you could get false negative results.
2. If you have unexplained non-intestinal symptoms (headaches, fatigue, joint pain) it may be worthwhile investigating for CD or gluten sensitivity, especially if you have other autoimmune conditions or a 1st-degree relative with CD.
3. Work with a dietitian to develop a nutrient-dense gluten-free diet if appropriate. Lots of whole foods are naturally gluten-free, but many gluten-free processed foods are more expensive, higher in calories, and lack nutrients obtained from gluten-containing whole grains (such as fiber, B vitamins, and protein.) To replicate the texture provided by gluten, they also often use ingredients that can be gastrointestinal irritants to people with IBS, such as xanthan gum.
Those pursuing a gluten-free diet for weight loss purposes should recognize any weight changes aren’t likely related to gluten but rather a reduction in calorie intake when eliminating previously consumed wheat-containing items. Individuals experiencing gastrointestinal symptoms without relief on a gluten-free diet may benefit from working with a dietitian experienced with the low FODMAP approach or other food sensitivities.
References
Aziz I, Hadjivassiliou M, Sanders DS. Does gluten sensitivity in the absence of celiac disease exist? BMJ. 345; 2012.
Sapone A, Bai J, Ciacci C, Doinsek J, Green PHR, Hadjivassiliou M, Kaukinen K, Rostami K, Sanders DS, Schumann M, Ullrich R, Villalta D, Volta U, Catassi C, Fasan A. Spectrum of gluten-related disorders: consensus on new nomenclature and classification. BMC Medicine. 10:13; 2012.
National Digestive Diseases Information Clearing House. http://digestive.niddk.nih.gov/ddiseases/pubs/celiac/ . Accessed March 30, 2014. Last updated January 27, 2012.
Catassi C, Bai JC, Bonaz B, Bouma G, Calabro A, Carroccio A, Castillejo G, Ciacci C, Cristofori F, Doinsek J, Francavilla R, Elli L, Green P, Holtmeier W, Koehler P, Koletzko S, Meinhold C, Sanders D, Schumann M, Schuppan D, Ullrich R, Vecsei A, Volta U, Zevallos V, Sapone A, Fassano A. Non-Celiac Gluten Sensitivity: The New Frontier of Gluten Related Disorders. Nutrients. 5(10): 3839-3853; 2013.
Shepherd SJ, Lomar MC, Gibson PR. Short chain carbohydrates and functional gastrointestinal disorders. Am J Gastroenterol. 108(5):707-717; 2013.
Molina-Infante J, Santolaria S, Montoro M, Esteve M, Fernandez-Banares F. Non-celiac gluten sensitivity: a critical review of current evidence. Gastroenterol Hepatol. doi: 10.1016/j.gastrohep.2014.01.005 [epub ahead of print].
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