Is IgE useful for Allergie?

IgE (Immunoglobulin E) is a key biomarker for immediate-type (Type I) allergic reactions. Elevated total IgE or specific IgE to particular allergens (e.g., pollen, foods) can indicate an allergy. However, IgE alone is not diagnostic: many individuals have elevated IgE without symptoms, and not all allergies (e.g., delayed Type IV reactions) are IgE-mediated. MyBody-X offers IgE blood tests as a screening tool, but clinical evaluation with history and possibly provocation tests remains essential. False positives and negatives are possible. The evidence for IgE utility in allergy is strong but context-dependent. Caveat: Do not self-diagnose or treat based on a single lab value.