14 Things You Need to Know About Celiac Disease

Celiac is an autoimmune disease triggered by the ingestion of gluten and other similar proteins found in wheat, rye, and barley among people with a genetic susceptibility to the disease, explains Stefano Guandalini, MD, founder and medical director of the University of Chicago Celiac Disease Center.

Celiac isn’t a food allergy, like the one people have with peanuts (allergies to wheat do exist, but mainly start in childhood and often disappear by adulthood, according to Food Allergy & Research Education). And it’s not an intolerance like lactose intolerance. Emphasizing the word “autoimmune” can clear up many misconceptions about the disease, says Daniel Leffler, MD, MS, director of clinical research at the Celiac Center at Beth Israel Deaconess Medical Center in Boston. Celiac disease is distinct from both allergies and intolerances, he says. “It’s more similar to other autoimmune conditions like type 1 diabetes or rheumatoid arthritis.”

Celiac disease also isn’t the same as the relatively new “non-celiac gluten sensitivity.” Doctors are still unpacking what this condition might mean, but there doesn’t appear to be any of the trademark GI damage of celiac disease with a sensitivity, says Dr. Guandalini.

Here’s what happens: You bite into a sandwich or eat a bowl of cereal and the gastric acid in your stomach goes to work breaking down the proteins in these grains. Some elements remain undigested though, so in people with celiac disease, lingering gluten proteins then prompt an immune reaction. The body attacks itself, damaging the small intestine.

Taking the brunt of this intestinal damage are the villi, finger-like structures lining the small intestine, where you absorb nutrients from your food into the bloodstream so they can do their job fueling, repairing, and generally helping your body function. Degeneration of the villi can lead to nutrient deficiencies. But the reaction isn’t only local—it can also create a cascading inflammatory response that “attacks other parts of the body, like joints, skin, and nerves, to create celiac symptoms around the body,” says Dr. Leffler.

Celiac disease can be difficult to parse because it’s not just GI symptoms that crop up. Some people with celiac are forced to make emergency trips to the bathroom or suffer abdominal pain after eating bread, but the disease doesn’t always hit like that. Kids with celiac disease most often come in with classic GI symptoms, like diarrhea or abdominal pain, but adults may not. In fact, only one-third of adults with celiac disease have diarrhea at all, according to the Celiac Disease Foundation (CDF). It’s not always glaringly obvious what’s going on, which is why the CDF estimates 2.5 million Americans with celiac are undiagnosed.

Just some of the more than 200 celiac disease symptoms include: abdominal bloating and pain, chronic diarrhea or constipation, vomiting, weight loss, iron-deficiency anemia, fatigue, joint pain, tingling or numbness in the legs, sores inside the mouth, tooth discoloration, unexplained infertility, and anxiety and depression.

The intensity of celiac disease symptoms isn’t always the same, either. “I have some patients who say they get bloated, but nothing bad. Others say they feel like they walk past a bakery and poop in their pants—this is not a one-size-fits-all disease,” says Mark T. DeMeo, MD, section chief of gastroenterology at Rush University Medical Center.

One out of 100 people worldwide are estimated to have celiac disease. Autoimmune conditions—including celiac—tend to cluster within families. If you have a first-degree relative with celiac disease, you have about a 10% chance of developing it. If you have a second-degree relative with celiac, your risk is up to 5% higher than someone with no family members with celiac, says Dr. Leffler, so you should get screened once a family member tests positive for the disease.

Another celiac disease risk factor is having an autoimmune condition in general. If you have one, you’re more likely to have another, according to Beyond Celiac, a non-profit organization that raises awareness about the disease. Finally, you may have a gene for celiac, although that doesn’t guarantee you’ll get the disease. Far from it: Up to 30% of the population carries these genes, according to the CDF.

Celiac is a genetic disorder, but a better term for it might be a partially genetic disorder, says Dr. Guandalini. While you need the gene for the disease to be triggered, “there are other factors that facilitate the onset of celiac, one of which is environmental,” he says. Such environmental factors include frequent use of antibiotics, particularly in the first month of life, as well as having been born via c-section, both of which can disturb the gut microbiome and trigger an immune response.

Infections, including the stomach flu, may also increase your celiac risk. Recent research from the University of Chicago that Dr. Guandalini co-authored pinpointed a specific infection that promoted an inflammatory response and the development of celiac in people who had a genetic predisposition to the disease.

At face value, celiac disease may sound rather mild, but left unchecked it can spark pretty significant future health issues. Severe intestinal damage due to celiac disease can lead to poor absorption of nutrients. When your body can’t pull the nutrients out of food and ferry them around, you suffer from nutrient deficiencies, which cause a host of other health problems, like osteoporosis, fertility issues, rashes, and anemia. In children, this can mess with development. “They can experience failure to thrive, delayed puberty, or a short stature,” says Dr. Guandalini.

Another serious risk of untreated celiac disease is inflammation. You’ve no doubt heard it’s the bad guy du jour for your body, implicated in all sorts of diseases like heart disease and type 2 diabetes. Chronic inflammation can even increase cancer risk. “Inflammation makes certain cells work extra hard and replicate faster than they should, which increases the chance of having genetic errors that can lead to cancer,” Dr. Leffler explains. Celiac patients may be susceptible to small bowel cancers or even lymphoma, since immune cells are also affected, thanks to the inflammation caused by celiac disease.

If you suspect you may be showing signs of celiac disease, it’s worth getting tested. One of the reasons so many people are undiagnosed is that celiac can show up in so many ways that the problem isn’t always obvious. “Often you hear people have had symptoms for 10 or 20 years and haven’t been treated effectively,” says Dr. Leffler. That was what happened with Marge Benham-Hutchins, 61, of San Antonio, Texas, a patient and family advisory council member at Beyond Celiac who was diagnosed in her early 50s. “At the time of my diagnosis, the gastroenterologist told me I had 20 years of damage to my small intestine,” she says.

If you’re suffering from persistent symptoms, like abdominal pain, fatigue, diarrhea, and headaches, talk to your doctor. The sooner you’re diagnosed, the sooner you can start treatment with a gluten-free diet, says Dr. Leffler.

Preliminary testing for celiac requires a simple blood test. “The blood tests we have to screen for celiac are very accurate, affordable, and widely available,” says Dr. Leffler. One is the tTG test, which screens for the tissue transglutaminase antibody, a protein often found in the blood of people with celiac disease. A positive test doesn’t mean that you definitely have celiac disease, but it gives doctors a hint that you do, says Dr. Guandalini. If a blood test is positive, a patient might go to a gastroenterologist who may run additional blood tests to confirm a celiac diagnosis. If blood tests aren’t clear, a specialist may want to do a biopsy of the small intestine or an endoscopy, a procedure where a small tube containing a camera is inserted down your throat to look for changes in the small intestine that would suggest celiac disease.

One thing to remember: Don’t stop eating gluten prior to being screened. You need to have at least two weeks (ideally four to six) where you’re eating gluten before taking the blood test. Otherwise, there’s a risk that the gluten will be cleared out of your system and antibodies won’t be present in your blood samples.

No matter how severe your symptoms, all celiac patients are advised to go on a strict gluten-free diet. “That is the only option,” says Dr. DeMeo. The goal is to feel better and ultimately heal the lining of the small intestine. Patients often notice their symptoms start to subside in just two weeks on a gluten-free diet, but healing can take up to two years, he says.

Since so many social activities revolve around food, let friends and family know if you’re avoiding gluten. “I tell people so that they may understand why I may decline invitations for restaurants or functions where it may be impossible for me to eat,” says Shannon Myers, 53, of Scottsdale, Arizona, who was diagnosed with celiac when she was 50, and is also a patient and family advisory council member at Beyond Celiac.

To call celiac part of a trend is a sad truth. In fact, 2.6 million people who don’t have celiac disease follow a gluten-free diet, says Dr. Gaundalini. With such a large consumer base, companies are coming out with gluten-free everything, and it’s easier than ever to find gluten-free menus at restaurants. That “blurs the strict need for a patient to be gluten-free,” he says.

If a server at a restaurant thinks you’re gluten-free to lose weight, they may not be as adamant about making sure your food isn’t contaminated. Patients need to express the severity of the situation. “I’ve posed the question, ‘What is safe for me to eat here,’ which puts an extra onus on the server to seriously think about what I can eat,” says Myers.

Also, while these new grocery store and restaurant choices are great for celiac patients, they also may prompt people to go on a gluten-free diet when they don’t need to, says Dr. DeMeo. According to research published in the journal the BMJ, doing so can have the surprising effect of raising your risk of heart disease, possibly because avoiding gluten may mean avoiding whole grains, which keep your ticker healthy.

With the expansion of the gluten-free market, you can be sure that beauty companies have hopped on board, offering a bevy of products made without gluten. Luckily, in most instances, you don’t have to go this far. Gluten has to be ingested for it to do damage, says Dr. Gaundalini. Shampoo, face cream, ointment, and the like are all safe for people with celiac disease, and you don’t have to worry about searching the label for gluten, although some patients do still choose to avoid such products with gluten in them. On the other hand, you’re more likely to swallow a bit of lipstick or toothpaste, so those products should be gluten-free.

Sometimes celiac disease symptoms are so sneaky, patients don’t notice them until after they’ve been diagnosed. One example Dr. Leffler hears patients talk about is brain fog. When they stop eating gluten, they realize a murky feeling going away. Others have told him they thought they were suffering from symptoms of early dementia. If these patients get exposed to gluten again, the fog rolls back in, and they realize it’s a symptom of celiac disease, he says.

Then there are the physical changes. After she healed, Myers could no longer eat whatever she wanted without gaining weight. Post-diagnosis, she put on 15 pounds in three years. That was a positive side effect of treatment, to be sure, as her body was finally absorbing her food properly, but one she wasn't anticipating.