Food Allergy

Food allergy is the immune system reacting to a specific food protein. It is different from food intolerance (like lactose intolerance, which is a digestive issue, not immune). True food allergies are less common than people believe — but when they are real, the reactions can be life-threatening, and they need to be managed seriously.

Common allergens in India

• Cow's milk and egg — in children; most outgrow by school age.
• Peanut and tree nuts (cashew, walnut, almond, pistachio) — often lifelong.
• Fish and shellfish (prawn, crab) — common in coastal India.
• Wheat — true IgE wheat allergy is rarer than coeliac disease.
• Soya, sesame (til).
• Fruits (banana, mango, kiwi, pineapple, orange) — often cause oral itching rather than full anaphylaxis.

Allergy vs. intolerance

• Allergy: minutes to 1–2 hours after food; hives, swelling, wheeze, anaphylaxis; IgE-mediated.
• Intolerance: hours later; abdominal cramps, bloating, diarrhoea; not life-threatening (lactose, FODMAPs).
• Coeliac disease is a separate autoimmune reaction to gluten — see Coeliac Disease.

Red flags — anaphylaxis (dial 112)

• Swelling of lips/tongue/throat, hoarse voice, difficulty breathing or swallowing.
• Wheeze, chest tightness.
• Dizziness, collapse.
• Widespread hives + vomiting or abdominal pain.
• Action: use adrenaline auto-injector if available, call 112, lie flat with legs raised, go to hospital. Antihistamines are NOT a substitute.

Diagnosis

• Clinical history first — what was eaten, how fast did symptoms start, what happened.
• Skin-prick test and specific-IgE blood tests at an allergist.
• Supervised oral food challenge is the gold standard when results are unclear.
• Random "food intolerance panels" (IgG tests) sold online are not evidence-based — they label many normal foods as "positive" and lead to unnecessary restriction.

Management

• Strict avoidance of the specific food — read labels, ask at restaurants, inform school/family.
• Adrenaline auto-injector for anyone with previous anaphylaxis — carry two, know how to use.
• Second-generation antihistamines for mild reactions (hives, itch).
• Oral immunotherapy for peanut allergy is an emerging option in specialist centres; not DIY.
• Children with milk/egg/wheat allergy — periodic re-evaluation; many outgrow.
• Wear a medical-ID bracelet or card for serious allergies.