What is IgG Antibody Reactivity Profile (184 foods)?
Food-specific IgG antibodies are produced when dietary antigens cross the intestinal epithelium and trigger an adaptive immune response. IgG is the most abundant immunoglobulin in serum and has a half-life of approximately three weeks, making it a marker of repeated or sustained exposure rather than acute reaction. The presence of IgG to a food may reflect normal immune tolerance, increased intestinal permeability, or an immunologically mediated sensitivity; distinguishing these scenarios requires clinical correlation. Unlike IgE-mediated allergy, which provokes immediate mast-cell degranulation, IgG reactions are postulated to involve immune-complex formation and delayed inflammatory pathways, though this mechanism remains contested in the allergy literature.