Celiac disease: symptoms, testing, and the gluten-free rule

Celiac disease is an immune reaction to gluten that damages the small intestine, and its symptoms spread far beyond the gut. The digestive ones: bloating, diarrhea or sometimes constipation, stomach pain, gas, and weight loss. The beyond-the-gut ones surprise people: iron-deficiency anemia that will not stay fixed, fatigue, brain fog, an itchy blistering rash on the elbows or knees, mouth ulcers, joint pain, missed periods or fertility trouble, and in children, poor growth. Many adults have few gut symptoms at all and are found through an unexplained anemia. Symptoms range from severe to silent, and silent damage still counts.

The first test is a blood test, usually tTG-IgA, that looks for the antibodies the immune system makes against gluten. The critical rule: you must still be eating gluten when the blood is drawn, because the antibodies fade within weeks on a gluten-free diet and the test goes falsely negative. If you have already cut gluten, tell the clinician before testing - guidelines call for eating gluten daily for several weeks first, and it is better to plan that than to get a misleading result. A positive blood test is followed by an upper endoscopy with small biopsies to confirm the intestinal damage.

With a strict lifelong gluten-free diet - no tablets, no surgery, but no cheating either. Gluten means wheat, barley, and rye, and the learning curve is real: obvious sources like bread and pasta, and hidden ones like soy sauce, some sauces, beers, and shared toasters and fryers. Oats are fine for most people if labeled gluten-free. A dietitian referral is part of proper treatment, not an extra, and most people's symptoms improve within weeks of going strictly gluten-free while the intestine heals over months. Even tiny regular exposures keep the damage going, which matters because unhealed celiac raises the risk of osteoporosis and other complications.

No. Celiac disease is an autoimmune condition with measurable antibodies and intestinal damage, and it carries long-term risks when untreated. Non-celiac gluten sensitivity causes similar symptoms but without the antibodies or the intestinal damage, and it does not carry the same risks. Wheat allergy is a third, different thing - a classic allergic reaction. The distinction matters because it changes how strict you must be and what follow-up you need, which is why testing before starting a gluten-free diet is worth the short wait.

Celiac itself is a marathon, not an emergency. Get prompt care rather than waiting when there is significant unintentional weight loss, signs of dehydration from persistent diarrhea, severe abdominal pain, vomiting blood or black stools, or fainting. In a child, poor growth or a swollen belly with ongoing diarrhea deserves timely evaluation. Those patterns are about finding out what is wrong this week, not waiting for a routine referral.

Yes for everything up to the endoscopy. A remote clinician can review the symptom pattern, order the tTG-IgA blood test to a lab near you - reminding you to stay on gluten until the draw - and refer for endoscopy when the blood test is positive. After diagnosis, the follow-up checks and dietitian guidance translate well to remote care too. Texting an AI doctor is a quick way to check whether your pattern justifies the test and to avoid the classic mistake of going gluten-free before the blood draw.