Supplementary material

Supplementary Materials: This ZIP file contains six supplementary items supporting the manuscript. Resource S1: Patient Screening Questionnaire for Histamine Intolerance. Resource S2: Low-Histamine Diet Implementation Guidelines. Resource S3: DAO Supplementation Protocol. Table S1: Detailed Characteristics of Included Studies. Table S2: AOC1 Gene Variants and Their Functional Consequences. Table S3: Clinical Features Associated with Histamine Intolerance in Fibromyalgia. These materials provide clinical tools and detailed research data to support the implementation and interpretation of findings presented in the main manuscript.