Purpose: The aim of this study was to find the correlation between the number, type, and placement of symmetric functional tooth units and the nutritional status using body mass index (BMI) and Mini Nutritional Assessment (MNA) in patients with both maxillary and mandibular removable partial dentures. Materials and Methods: A randomized study was conducted at the Clinic for Prosthodontics, School of Dentistry, University of Belgrade, Serbia, followed by determination of number of functional tooth units. After insertion of the prostheses, the nutritional status was assessed, using BMI and MNA form. Nutritional status was reviewed 12 months after prosthetic treatment. Number of teeth and age were analyzed using analysis of variance and t test. For other variables such as BMI baseline, BMI follow-up, MNA baseline, MNA follow-up, change in BMI, and change in MNA, Kruskal-Wallis Test or Mann-Whitney Test were used. Results: The results on the MNA changes showed that patients with symmetric natural functional tooth units had significantly higher values (2.9 ± 0.8) compared with patients without natural functional tooth units (1.9 ± 0.6) or with asymmetric natural functional tooth units (1.6 ± 0.4). Patients with asymmetric artificial functional tooth units had significantly lower change in MNA (1.9 ± 0.4) than those with symmetric artificial functional tooth units (2.6 ± 0.9). Conclusion: The findings of this study suggest that adequate rehabilitation with symmetric positioning of the functional tooth units can improve the nutritional status of partially edentulous patients.