Immune vs Non-Immune Reaction Pathways
Two different biological systems drive food reactions.
- Immune: Allergy pathway (IgE antibodies involved)
- Non-immune: Intolerance pathway (Enzyme or chemical basis)
- ~8%: Global food allergy rate (children, approx.)
- ~65%: Lactose intolerance rate (adults worldwide, approx.)
Immune system engagement
Allergy involves antibodies; intolerance does not, placeholder text.
Rapid Mast Cell Degranulation Response
IgE cross-linking triggers fast histamine release.
- <30 min: Typical onset (after allergen exposure)
- Histamine: Key mediator (released from mast cells)
- IgE: Key antibody (binds allergen and receptor)
- Anaphylaxis: Worst outcome (systemic, life-threatening)
Sensitization and re-exposure
First exposure sensitizes; second exposure triggers reaction, placeholder.
Lactase Deficiency and Delayed Digestive Symptoms
Missing enzyme leads to slow bacterial fermentation symptoms.
- 30–120 min: Typical onset (after ingestion)
- Lactase: Missing enzyme (breaks down lactose sugar)
- Fermentation: Symptom source (gut bacteria produce gas)
- None: Immune cells involved (purely digestive mechanism)
Undigested sugar fermentation
Bacteria ferment lactose producing gas and bloating, placeholder.
Life-Threatening Anaphylaxis vs Mild Discomfort
Allergy severity can escalate quickly; intolerance stays mild.
- Anaphylaxis: Allergy worst case (airway, blood pressure risk)
- Discomfort: Intolerance worst case (cramps, bloating, diarrhea)
- Allergy only: Fatality risk (intolerance rarely fatal)
- Intolerance: Dose dependence (symptoms scale with amount)
Risk stratification
Severity differs sharply between the two mechanisms, placeholder.
Differentiating Tests for Allergy and Intolerance
Different tests confirm each mechanism accurately.
- Skin prick/IgE: Allergy test (detects specific antibodies)
- Breath test: Intolerance test (measures hydrogen gas)
- Both: Elimination diet (used for confirmation)
- Oral challenge: Gold standard allergy (supervised food challenge)
Choosing the right test
Testing approach depends on suspected mechanism, placeholder.
Correct diagnosis prevents unnecessary food avoidance, placeholder sentence.