The Effect of Chlorhexidine Mouthwash on Postprandial Glucose Response in Healthy Individuals

Blood glucose is measured at baseline and following food intake using a blood glucose meter (ACCU-CHEK Performa, Roche, USA). Participants are then provided with 10 mL of the assigned mouthwash according to randomisation. Mouthwashes are blinded for both researchers and participants, as they are prepared by an external individual, covered, and labelled with group numbers. This ensures that neither participants nor researchers can identify the treatment allocation.

Oral rinsing is performed for 2 minutes before participants spit out the mouthwash. The mouthwashes used include:

Chlorhexidine di-gluconate (0.2%) (Corsodyl, GlaxoSmithKline, England) Placebo (water with yellow food colouring)

Following the mouth rinse, participants consume a pre-weighed breakfast meal consisting of 40 g of Hubbard's Foodstore® strawberry jam (Sainsbury's Supermarkets Ltd., London, UK) spread over 50 g of soft white bread (Sainsbury's Supermarkets Ltd., Northern Ireland, UK).

Blood glucose measurements are taken at 15, 30, 45, 60, 90, and 120 minutes post-meal.Baseline blood glucose values are used as reference points. For analysis, only the differences between baseline and subsequent time-point measurements are considered. The mean iAUC is calculated for each mouthwash condition (chlorhexidine and placebo).

Each participant completes the protocol twice, once for each mouthwash condition, with a minimum washout period of 48 hours between sessions.

Inclusion criteria

Healthy adults (> 18 years/old)

Exclusion criteria

The main exclusion criteria is pregnancy, people following cancer treatment, taking immunosuppressant or antibiotics and using antibacterial mouthwash for less than 2 weeks before the study.