Celiac disease
An autoimmune disorder where gluten — a protein in wheat, barley, and rye — triggers the immune system to attack the small intestine.
What it is
Celiac disease affects around 1.4% of people worldwide. The most common symptoms are diarrhea and/or constipation, bloating, and malnutrition, but it can also show up in less obvious ways — anemia, osteoporosis, an itchy skin rash called dermatitis herpetiformis, and even neurological symptoms.
The gluten-free diet is the treatment
Unlike many conditions on this site, celiac disease has one clear, well-established treatment: strict, lifelong avoidance of gluten. Most people see symptoms improve within days to weeks of full adherence, and the small intestine gradually heals.
Cross-contamination is the hidden risk
About half of people with celiac disease still experience ongoing gut inflammation, often from unintentional trace gluten exposure rather than knowingly eating gluten. Shared toasters, cutting boards, frying oil, and cooking surfaces are common culprits. Checking for a certified gluten-free label matters too — labeling regulations cap gluten at 20 parts per million, but that threshold isn't zero.
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