Gastroesophageal reflux disease (GERD) is a prevalent chronic condition affecting the well-being of both adults and children in general medical practice. Research on the effects of fermented soy-bean (FSB) supplementation in managing GERD is relatively new, with limited studies available. Existing research often lacks sufficient dosing regimens and study durations to differentiate be-tween transient placebo effects and sustained benefits. In this study, the beneficial effects of FSB supplementation were investigated in 50 voluntary participants. Participants were required to take 1g of FSB supplement once daily for twelve weeks. GERD symptoms were evaluated using the Reflux Disease Questionnaire (RDQ), while inflammatory markers, including interleukin-4 (IL-4), interleukin-6 (IL-6), and interleukin-8 (IL-8), were measured to assess inflammation. The Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire was used to evaluate partici-pants' quality of life. Results indicated that FSB supplementation significantly (P<0.05) alleviated heartburn and regurgitation symptoms and reduced levels of IL-4, IL-6, and IL-8, indicating a notable anti-inflammatory effect. Additionally, significant (P<0.05) improvements were observed in QOLRAD scores, particularly in vitality, emotional distress, and physical/social functioning. Collectively, our findings support the use of FSB as an adjuvant approach in managing GERD, with notable improvements in patients' quality of life.

Inclusion Criteria:

(1) experienced heartburn, acid reflux, regurgitation, or non-cardiac chest pain within the past three months; (2) aged 18 years or older; (3) demonstrated the ability to comprehend the study protocol and information provided by the investigators; and (4) provided in-formed consent.

Exclusion Criteria:

1) use of medications related to GERD, such as acid inhibitors, antacids, prokinetics, gastric mucosal protectors, herbs, probiotics, or related preparations within the past two weeks; (2) a history of gastro-esophageal or duodenal surgery; (3) diagnosis of peptic ulcer, gastrointestinal bleeding, esophageal or gastric varices, or upper GI malignancies confirmed by endoscopy at tertiary hospitals; and (4) pregnancy or lactation

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. All of the individual participant data collected during the trial, after deidentification will be shared upon reasonable request. Additional docu-ments including study protocol, statistical analysis plan, informed consent form and clinical study report will also be made available. The data will be available immediately following pub-lication with no end date. Data will be shared with anyone who wishes to access with reasonable request. The data can be used for any types of analyses.

Same appearance of the supplements given. Identity of participant was masked during examination.