Happy Celiac Awareness Month!
Testing for Celiac Disease and Gluten Sensitivity
As a wellness coach with a specialty in gluten-free living, I am often questioned about testing for celiac disease (CD) and gluten sensitivity. In honor of Celiac Awareness Month, I have written this article to share what I’ve learned about testing. I hope you find it informative and useful.
Gluten sensitivity is defined as an immune response by the body to the protein molecules of certain types of “gluten” found in the kernels of wheat, rye and barley (see graphic below). Other grains such as rice, corn and millet have gluten as well but these gluten molecules appear to be less toxic to people with gluten sensitivity. Keep in mind although, one can have sensitivity to the gluten in these grains as well. Dr. Alessio Fasano, center director at Maryland Center for Celiac Research, estimates that that gluten sensitivity affects 6-7% of the population which works out to one in five people. Other researchers have estimated it affects up to 50% of the population.
Gluten sensitivity can affect people in a variety of ways. According to Dr Vikki Peterson, author of The Gluten Effect, over 100 diseases and 300 symptoms have been associated with gluten sensitivity including arthritis, Hashimoto’s disease, certain types of diabetes, lupus, multiple sclerosis (or MS) as well as neurological disorders such as autism, depression, anxiety, migraines and even schizophrenia. It is also the cause of CD a genetic autoimmune condition where the body’s immune system attacks and damages the villi of the small intestine. The villi are like small tiny fingers or “shags” (like shag carpeting) that greatly increase the surface area of the intestine maximizing absorption of nutrients. Once damaged the villi become flattened thereby drastically decreasing the possibility of nutrient absorption which can result in deficiencies. CD affects 1% of the population which is around 3 million Americans with an estimated 95% undiagnosed. It can lead to a number of serious complications including anemia, osteoporosis, infertility, thyroid disease and cancer.
Non-Celiac Gluten Sensitivity (NCGS) involves a different type of immune response to gluten. The immune system attacks the gluten protein molecule as if it is an invader and responds with inflammation both inside and outside the digestive system. It is not yet researched on how this immune response affects your overall health including possibly related auto-immune conditions. It is estimated that NCGS affects 16 million Americans or one in four people. Another type of immune response to gluten is an allergic reaction referred to an IgE immune response. It can be measured through a skin prick or a blood draw. See the diagram below for each type of immune reaction. Whether you have CD or NCGS, the symptoms can cover a broad range including bloating, gas, anemia, hair loss, chronic constipation, diarrhea, fatigue, lack of concentration and skin rashes. The most common symptom among children is irritability. Other disturbing symptoms in children with CD are delayed growth or puberty and thinning bones which can lead to increased fractures.
Testing for both CD and gluten sensitivity can be frustrating. The current recommendations for CD testing according to the National Foundation of Celiac Awareness are: anti-tissue transglutaminase antibody (iTG – IgA and IgG) and total serum IgA which are measured through a blood draw. The test recommended for children under two years old is anti-gliadin antibody (AgA –IgG and IgA). It is important to be consuming gluten at the time of these tests as they measure the response to gliadin, just one of the many peptides of gluten. If you have already eliminated gluten from your diet or are sensitive to one or more of the other peptides in gluten (other than gliadin) the test may come out negative. If the blood test is positive, a colonoscopy and an upper endoscopy will be ordered to confirm whether villi damage is present. Keep in mind a positive blood test is not a CD diagnosis. The verification of damaged villi is what warrants the official diagnosis. Genetic testing through a blood draw or cheek swap is also available to see if you are susceptible to CD. Ninety plus percent of people diagnosed with CD carry one or both of the genes, HLA DQ2 and HLA DQ8. If you carry one or both of these genes, but test negative to everything above, there is a strong possibility you could be gluten sensitive and develop CD later in life. Please note, detection of the genes does not mean you have CD but rather the potential to develop it. If the genes are absent, the likely hood of one developing CD is very slim (but still possible).
Most of the tests above can be ordered through your general practitioner with the exception of the gene cheek swap. This test can be ordered through this direct-to-consumer lab, Entero Lab. If you test negative to the iTG – IgA, IgG and total serum IgA tests but have a strong suspicion that you or your child could be gluten sensitive, there are new gluten sensitivity panels available through Cyrex Laboratories that can test for sensitivities to 10 peptides of gluten rather than just gliadin. The gluten sensitivity panel is currently debated by some medical circles and is typically not covered by insurance. The test can be ordered and interpreted through qualifying practitioners.
Testing is especially important if CD runs in your family. According to the University of Chicago’s Celiac Center, the prevalence of CD in the US is “1 in 133” for average healthy people. For those with first-degree relatives (parent, child, sibling) diagnosed with CD, the prevalence makes a drastic jump to “1 in 22.” In people with second-degree celiac relatives (aunt, uncle, cousin), it’s “1 in 39.”
Keep in mind that any negative test result does not mean that it is safe for you to consume gluten. The gold standard, as of right now, is a gluten challenge. Take gluten out of your diet and if you feel better, there is a good possibility you could have a sensitivity to it. The challenge requires 100% clean up of your diet though. Research to discover the many places gluten can lurk including toasters and cutting boards, etc. The average time for a patient to be accurately diagnosed with CD is 6-10 years. A lot of damage can be done during that time. In a landmark US prevalence study, 60% of children and 41% percent of adults were asymptomatic (without symptoms) when diagnosed. CD can be silently damaging the body. In a 1999 study, children diagnosed between the ages of 4-12 are 50% less likely to develop an auto-immune issue caused by CD making early detection crucial.
The prescription for CD or NCGS is a strict lifetime adherence to a gluten-free lifestyle. Besides the obvious foods such as bread, cake, crackers and pasta, gluten can also lurk in soy sauce, gravies, adhesives, play dough, skin products (wheat germ oil) and vitamins to name a few. The gluten-free market has grown tremendously making it easier than ever for a person with gluten sensitivity to eat safe foods. Keep in mind, most people with CD or NCGS have gut inflammation and intestinal permeability (AKA Leaky Gut). It is imperative to eat a healthy diet of nutrient dense organic foods to help facilitate healing and cool inflammation. Half of your food consumption should consist of vegetables and limited low-glycemic fruits such as berries and cherries. Lean clean protein and healthy fats are also imperative to healing the gut. There are many gluten-free grains you can experiment with including brown rice, millet, buckwheat, quinoa, sorghum and teff. Individuals going gluten-free should work with a practitioner and/or nutritionist to monitor nutritional levels to avoid deficiencies. There are many great supplements available to help heal the gut and reduce inflammation.
Connecting with a support groups can also be very beneficial. Search your area for a group. You can check the Gluten Intolerance Group (GIG) of America Web site for local support groups. Many celiac centers or organizations have support groups as well. If you or your children are gluten sensitive, reach out for help. Taking control of your family’s health can be very empowering and prevent serious health issues down the road.
Watch for my post next week. I will share one of my favorite naturally gluten-free spring time meals. Meanwhile, be well and continue to thrive gluten-free.