Background <p>The aim of this pilot study was to evaluate the effects of probiotic supplementation and diet-supported probiotic use on periodontal clinical parameters in individuals with periodontitis.</p> Methods <p>A total of 120 female participants aged between 20 and 60 years, diagnosed with periodontitis and without systemic diseases, were included in the study. Participants were randomly assigned into three groups: control group (conventional treatment), probiotic group (conventional treatment + probiotics), and diet + probiotic group (conventional treatment + probiotics + personalized diet). Clinical evaluations were performed using measurements of probing depth (PD) and clinical attachment loss (CAL), while dietary intake was assessed using three-day food records. Data were analyzed using SPSS 21.0 software, and <i>p</i> &lt; 0.05 was considered statistically significant.</p> Results <p>After a six-week follow-up, significant reductions in PD and CAL were observed in the probiotic and especially the diet-supported probiotic groups (<i>p</i> &lt; 0.001). In the diet + probiotic group, PD improved by 41.5% and CAL by 42.7%. Nutritional analysis revealed that protein and fiber intake supported periodontal improvement, whereas sugar and carbohydrate consumption had negative effects (<i>p</i> &lt; 0.05).</p> Conclusion <p>Probiotics were found to support periodontal healing, and this effect was significantly enhanced by a personalized anti-inflammatory diet. It is recommended that probiotics and balanced nutrition be integrated into a holistic approach in the treatment of periodontitis.</p> Trial registration <p>ClinicalTrials.gov Identifier: NCT06944938, First Submitted: 10/04/2025 (Retrospectively registered) First Posted: 25/04/2025.</p>