| Condition | Cause | Major Triggers | Symptoms | Immune System Involvement | Onset Time | Diagnostic Tests | Treatment | Cross-Reactivity |
| Wheat Allergy | IgE-mediated immune reaction to wheat proteins | Wheat proteins (Omega-5 Gliadin, LTPs, ATIs) | Hives, swelling, wheezing, nausea, vomiting, anaphylaxis (severe cases) | IgE antibodies trigger mast cell activation and histamine release | Minutes to hours after wheat consumption | Skin prick test, serum IgE, oral food challenge | Strict wheat avoidance, epinephrine for anaphylaxis | Possible with barley, rye, oats, grass pollen, LTP-containing fruits/nuts |
| Celiac Disease | Autoimmune reaction to gluten damaging the small intestine | Gluten (Gliadin, Glutenin) | Chronic diarrhea, weight loss, bloating, fatigue, malabsorption | Autoimmune T-cell response leading to villous atrophy | Gradual, over weeks or months with gluten exposure | Tissue transglutaminase (tTG-IgA) test, biopsy of the small intestine | Lifelong gluten-free diet (strict avoidance of wheat, barley, rye) | No IgE cross-reactivity, but gluten-containing grains (wheat, barley, rye) must be avoided |
| Gluten Intolerance (NCGS) | Non-autoimmune, non-IgE reaction to gluten-containing foods | Gluten and wheat components, but without autoimmunity | Bloating, brain fog, headache, abdominal pain, fatigue | Innate immune response with inflammation, but no autoimmunity | Hours to days after consuming gluten | No definitive test; diagnosis by elimination diet | Gluten reduction or avoidance, based on symptom management | No proven cross-reactivity, but some report sensitivity to FODMAPs |
Key Differences:
- Wheat Allergy is an IgE-mediated reaction, leading to immediate allergic symptoms (hives, swelling, anaphylaxis).
- Celiac Disease is an autoimmune disorder, where gluten damages the small intestine, causing malabsorption and long-term health issues.
- Gluten Intolerance (NCGS) is not autoimmune or allergic, but causes digestive and neurological symptoms after consuming gluten.
- Only Wheat Allergy can trigger life-threatening anaphylaxis, requiring strict avoidance and emergency epinephrine treatment.
- Celiac Disease and Gluten Intolerance require a gluten-free diet, but Wheat Allergy is specific to wheat proteins and may allow gluten from other sources (barley, rye, oats) in some cases.