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- Celiac disease symptoms include bloating, gas, constipation, and abdominal pain.
- A common, but lesser-known, celiac disease symptom is an itchy rash with small blisters.
- If celiac disease is untreated, other symptoms include unexplained weight loss and anemia.
- Visit Insider's Health Reference library for more advice.
An estimated 2.5 million Americans don't know they have celiac disease, an autoimmune disorder in which eating gluten damages the small intestine.
This may be due to the fact there are over 200 known symptoms of the condition, meaning it affects everyone differently. What's more, not all signs and symptoms may be present.
The following 10 signs of celiac disease are by no means an exhaustive list, but a good starting point if you suspect you have the condition.
1. Celiac disease rash
About 17% of people with celiac disease develop dermatitis herpetiformis, an itchy rash characterized by small blisters on the knees, elbows, lower back, or buttocks.
For people with celiac, dermatitis herpetiformis typically occurs within a month of consuming gluten, said Lizz Kinyua, MD, a medical consultant for Oh So Spotless.
In fact, many people develop a celiac disease rash without any digestive symptoms, making it an important first sign of the condition.
2. Gas
Some of the first signs of celiac disease are digestive problems, like gas.
While gas isn't always connected to a digestive disorder - it can also be caused by dietary changes, like an increased fiber intake - you should see your doctor if gas is persistent, interferes with your daily life, or is accompanied by other GI symptoms like bloating.
3. Diarrhea
Loose, watery stool is one of the most common symptoms of celiac disease, with one study finding it affected about 77% of patients.
People with celiac most likely experience diarrhea due to intestinal inflammation and damage caused by gluten, says Patrick Griffin, MD, gastroenterology specialist and Chief Medical Officer of 9 Meters Biopharma.
4. Abdominal pain
Another common initial sign of celiac disease is dull, mild abdominal pain after eating.
Fortunately, a gluten-free diet seems to be effective for improving this symptom. For example, a 2016 study found that untreated celiac patients had significantly more abdominal pain than those who were on a gluten-free diet.
5. Iron-deficiency anemia
If celiac disease is left untreated, the lining of the small intestine becomes so damaged, it is unable to properly absorb nutrients like iron, says Kinuya. This can cause an iron deficiency, which may ultimately lead to anemia.
Anemia is a condition where red blood cell count is abnormally low. It's associated with symptoms such as extreme fatigue, weakness, chest pain, headaches, and dizziness. A 2013 study found that 23% of celiac patients were anemic.
6. Peripheral neuropathy
About 10% of people with celiac disease also have an associated neurological condition like peripheral neuropathy, due to an inability to absorb vitamin B12, says Kinuya.
Peripheral neuropathy causes weakness, pain, or a burning/tingling sensation in the hands and feet due to nerve damage. It is more likely to be experienced in the late stages of untreated celiac.
7. Unexplained weight loss
Despite no changes in diet or appetite, celiac disease may lead to weight loss as the intestines can no longer absorb nutrients, says Griffin.
In fact, a small 2012 study found that 23% of celiac disease patients experienced weight loss. Another 2012 study of newly diagnosed celiac patients found that of the small percentage who were underweight, 69% gained weight after one year on a gluten-free diet.
8. Bloating
Due to inflammation in the digestive tract, celiac disease can also cause bloating. A small 2013 study found that bloating was the fourth-most common gastrointestinal symptom of celiac disease, affecting 11% of patients.
However, once you adhere to a strict gluten-free diet, this symptom should resolve.
9. Fatigue
Over time, poor absorption of certain nutrients can cause a general feeling of fatigue or decreased energy in people with celiac disease. Sometimes, the fatigue can be attributed to iron deficiency anemia.
In fact, a small 2010 study found that celiac disease patients who did not receive treatment had significantly worse fatigue than those who adhered to a gluten-free diet.
10. Constipation
Another common GI symptom of celiac disease is constipation, probably due to the fact damaged intestines absorb more moisture from stool, says Griffin. This leads to a hardened stool that's more challenging for your body to pass.
While most symptoms should resolve after starting a gluten-free diet, a small 2021 study found that 29.7% of people continued to experience constipation after starting a gluten-free diet. This may be because a gluten-free diet tends to be lower in fiber, which can reduce constipation.
Insider's takeaway
Celiac disease is a lifelong condition triggered by gluten. While there is no cure, people with the condition can manage their symptoms with a strict gluten-free diet. But an early diagnosis of celiac disease is important because if left untreated, the disorder can lead to serious complications.
"Celiac disease is a chronic disease that, if not diagnosed, can lead to far worse complications such as coronary artery disease, ulcerative colitis, and even lymphoma," says Kinyua.
Talk with your doctor if you experience any persistent digestive discomfort, diarrhea, or other symptoms lasting more than two weeks. Your healthcare provider can then conduct a blood test and endoscopy to determine if you have celiac disease and need to go on a gluten-free diet.