Background: Capsaicin receptors are abundant in the esophagus of NERD (non-erosive reflux disease) patients. Heartburn may develop by acid stimulation of these receptors during gastroesophageal refluxes (GER) and may be improved by desensitization with capsaicin-containing chili.
Objective: To determine the therapeutic effects of chronic chili ingestion on GER symptoms in NERD patients.
Methods: Eight NERD patients with a positive 24 hr pH test were included. Patients were randomized to receive either chili powder in 2 gelatin capsules orally or identical-looking placebo capsules three times per day before meals (total capsaicin 2.7 mg/day in the capsaicin group) for 6 weeks, in a randomized double-blinded crossover fashion with a 6-week washout period. Heartburn, food regurgitation, epigastrium burning, epigastrium pain, abdominal fullness, nausea, chest discomfort, and early satiety symptom scores were assessed by 10-cm long visual analog scales (VAS) at week 0, 1, 2, 4, and week 6. Total symptom scores (the sum of all scores), GERD symptom scores (the sum of heartburn, acid regurgitation and food regurgitation scores), and each individual symptom score were compared between the chili treatment group and the placebo group. Two-hour postprandial acid and non-acid refluxes were evaluated in all patients at baseline and the end of treatment, using the MII-pH (Multichannel Intraluminal Impedance-pH) monitoring after ingestion of a cup of noodle soup with 2 grams of red chili powder.
Results: All patients completed the study without serious adverse events. At baseline, the total symptom scores (26 ± 14 vs 22 ± 16), GERD scores (7.6 ± 3.7 vs 4.7 ± 2.8), and individual symptom score were not statistically different in the chili and the placebo groups (p >0.05). Ingestion of chili could significantly lower total symptom scores (10 ± 9 vs 20 ± 14), GERD symptom scores (0.9 ± 1.2 vs 4.9 ± 2.4), heartburn symptom scores (0.4 ± 0.6 vs 3.7 ± 1.6), and food regurgitation symptom scores (0.5 ± 0.8 vs 1.3 ± 1.6) in NERD patients compared to placebo at the end of treatment (p <0.05). Other symptoms were not significantly improved by red chili (p >0.05). The significant improvement of heartburn and food regurgitation was observed by the end of week-2, and persisted up to the end of treatment. Although the number of gastroesophageal refluxes was decreased, the numbers and the durations of the 2 hours postprandial acid and non-acid refluxes were not significantly different in the chili and the
placebo groups, whether before or at the end of treatment (p >0.05).
Conclusions: Chronic chili ingestion was shown in this study to improve heartburn and food regurgitation
symptom in NERD patients compared to placebo, without significant effects on postprandial gastroesophageal
acid/non-acid refluxes. The results suggested that capsaicin-containing red chili improved GERD symptoms mainly
by its effect on esophageal sensation, rather than on the lower esophageal sphincter functions.