Three distinct categories with three very different risk levels — here's how to tell them apart.
An immune system response (via IgE antibodies) that can cause symptoms ranging from hives to life-threatening anaphylaxis — even trace amounts can trigger it, and it's diagnosed through allergy testing.
A digestive issue, not an immune response (lactose intolerance is the classic example) — uncomfortable, often dose-dependent, but not life-threatening.
A looser, less clinically defined term for foods that seem to cause symptoms without a confirmed allergic or intolerance mechanism — genuinely real for some people, harder to test for definitively.
A true allergy requires strict avoidance and, often, carrying emergency medication — a fundamentally different risk level than an intolerance, which is usually about comfort and dose rather than danger.
If you suspect an allergy — especially with any history of severe reactions — get properly tested by an allergist rather than self-diagnosing through elimination alone.