IBS-Specific IgG ELISA-Based Elimination Diet in IBS

The IBS-specific IgG ELISA-based elimination diet is a personalized dietary intervention designed to address food sensitivities in individuals with irritable bowel syndrome (IBS). This approach leverages an IgG antibody assay to identify specific food triggers that may contribute to IBS symptoms, such as abdominal pain, bloating, and altered bowel habits. The study evaluating this diet aimed to improve upon methodological flaws seen in earlier IgG-related dietary research.

In a randomized, double-blind, sham-controlled multicenter trial conducted across 8 centers, adults with IBS who tested positive for one or more food sensitivities via the IgG assay were assigned to either an antibody-guided elimination diet or a sham diet for 8 weeks. The experimental group excluded foods identified as triggers by the IgG assay, while the sham group followed a diet excluding random foods.

The primary outcome was achieving a clinically meaningful reduction in abdominal pain intensity (≥30%) for at least 2 of the final 4 weeks of treatment. Results showed that the experimental group had significantly higher response rates compared to the sham group (59.6% vs 42.1%; P = .02). Subgroup analysis revealed stronger improvements among individuals with constipation-predominant IBS (IBS-C) and mixed-type IBS (IBS-M).

These findings suggest that the IgG-guided elimination diet may serve as a safe, non-pharmacologic treatment option for IBS, particularly for patients unresponsive to conventional therapies. However, larger trials are needed to confirm these results, refine dietary protocols, and assess long-term efficacy and adherence.