Food sensitivity
A vague term for uncomfortable reactions to foods that are neither an allergy (no IgE) nor a clearly established enzyme intolerance, with mechanisms often poorly understood.
« Food sensitivity » is an imprecise, catch-all term. It describes unpleasant reactions to certain foods that fit neither the allergy box (IgE immune reaction) nor the classic enzyme intolerance box (such as lactose). It is a grey area.
A fresh angle (beware of false tests): a crucial and protective point, many commercial « food sensitivity » tests (measuring IgG antibodies to foods) are sold but not scientifically validated. Allergy societies (EAACI and others) formally advise against them.
Why? IgG antibodies to foods are in fact a normal sign of exposure and tolerance (not a pathological reaction). A high IgG level to a food often simply means you eat it often! Relying on these tests leads to unjustified exclusion of many foods, with a risk of deficiencies, eating disorders and anxiety, for no benefit.
The real possible mechanisms: behind a genuine « sensitivity » there may be:
- FODMAPs (fermentation → bloating), the most common cause
- Histamine intolerance (DAO deficiency)
- Gluten/wheat (via FODMAPs or non-coeliac gluten sensitivity)
- Gut dysbiosis causing hypersensitivity
- Additives (sulphites, glutamate in some people)
- A stress/gut-brain axis component (IBS)
The right approach: rather than a dubious test, the reliable method is a food diary plus a supervised elimination and reintroduction (ideally with a professional). You identify the real triggers objectively, without needlessly cutting out healthy foods.
In practice: be wary of « sensitivity » tests sold online or in pharmacies; seek advice for a structured approach; do not heavily restrict your diet on the basis of beliefs or unreliable tests.