When is an intolerance an allergy? And why do some suffer more than others?
Pray for me, for I am planning a group camping trip. Two of our group cannot eat gluten. One can’t do dairy. One swells up when bitten by mosquitos, and half of us have hay fever. Were we always so allergic to our food and environment? The camping trips of my childhood seemed a whole lot simpler to organise: Army tents, roll mats, singed meat and white rolls.
What has happened to us since then? In fact, research by the NHS out at the end of July showed that the rate of dangerous allergies has more than doubled in the past 20 years, now causing 25,000 NHS hospital stays a year. For severe food-related allergic reactions, the rise in admissions is even greater.
Are we itchy, sniffling and bloated campers actually allergic, or just intolerant to the things that cause us grief? Many of us are unsure and the only way to establish the root cause of our symptoms is by consulting a doctor, who’ll then take a detailed case history and conduct allergy tests. There’s a tendency, these days, for people to self-diagnose, often declaring they’re “allergic” to wheat or dairy.
Yet according to Dr Adam Fox, consultant paediatric allergist at Guy’s and St Thomas’ hospitals, allergies and intolerances are “scientifically very clearly delineated”. The word “allergy” stems from the Latin for “other response”. Typically, the immune system, Fox explains, reacts to foreign substances in one of two ways: either it recognises them as benign (food, say) and ignores them, or identifies them as infectious agents (like bacteria, or viruses) and attacks them. Allergic reactions involve a third response.