Application of a Fasting-mimicking Diet in Obese Patients With Periodontitis Stage III-IV

This study will evaluate whether a fasting-mimicking diet (FMD) can improve the systemic and periodontal response to non-surgical periodontal treatment in obese adults with severe periodontitis. Periodontitis is a serious inflammatory disease that damages the tissues supporting the teeth and may also contribute to inflammation elsewhere in the body. Obesity is also associated with increased systemic inflammation, which may worsen periodontal disease and affect treatment outcomes.

In this pilot randomized cross-over clinical trial, eligible participants will receive full-mouth non-surgical periodontal therapy and will be assigned either to an FMD group or to a control group continuing their usual diet. The FMD will be administered in three 5-day cycles around the periodontal treatment period. After a wash-out period, the groups will switch interventions.

The study will assess whether FMD can reduce systemic inflammation, measured primarily by serum C-reactive protein (CRP), and improve periodontal healing after treatment. Additional outcomes include clinical periodontal measurements, inflammatory markers in gingival crevicular fluid, and changes in oral and gut microbiota. Findings from this study will help determine the feasibility of this dietary approach and provide preliminary data for a larger clinical trial.