Effects of dihydrocapsiate on salivary secretion in healthy subjects: A randomized, double-blind, placebo-controlled, crossover study

Abstract

Purpose: We aimed to assess the effects of dihydrocapsiate (DHC), a non-pungent capsaicin analog, on salivary secretion in individuals experiencing mild dry mouth symptoms. Given the function of transient receptor potential vanilloid 1 (TRPV1) in salivation, we hypothesized that DHC, which activates TRPV1 with minimal irritation, could serve as a novel therapeutic agent for dry mouth (xerostomia).

Methods: A randomized, double-blind, crossover trial was conducted involving healthy adults aged 40 to 70 years who reported a tendency toward dry mouth. Participants were randomly assigned to receive either a test tablet containing 0.8 mg DHC or a placebo tablet. Saliva secretion was measured using a spitting method before and after tablet administration, with assessments conducted in the morning to minimize diurnal variations. For statistical comparisons, paired Student’s t-tests were applied.

Results: DHC intake significantly increased salivary secretion relative to the placebo group (p < 0.05). No adverse events or significant changes in safety parameters, including body weight, BMI, or blood pressure, were recorded during the study.

Conclusion: DHC effectively enhanced salivary secretion while minimizing the pungency associated with capsaicin. Its ability to stimulate TRPV1 with low irritation suggests potential as a safe and convenient therapeutic option for individuals experiencing dry mouth. 

Novelty: This study is the first randomized, placebo-controlled trial to demonstrate that dihydrocapsiate (DHC), a non-pungent capsaicin analog, significantly enhances salivary secretion in healthy individuals. These findings suggest that DHC may serve as a novel and tolerable functional ingredient for the management of oral dryness.

Keywords: dihydrocapsiate (DHC), capsaicin, TRPV1, salivary secretion, xerostomia, dry mouth.