Background: Vitamin D and calcium deficiency in the diet accelerate bone loss and osteoporosis. We investigated if taking vitamin D and calcium supplements impacts periodontal disease status since vitamin D metabolites may alter the inflammatory response and have antimicrobial effects. Methods: A total of 51 patients were recruited from two dental clinics who were getting periodontal maintenance therapy. 23 of them were taking vitamin D (400 international units/day) and calcium (1000mg/day) supplements, while the remaining 28 were not. All of the participants experienced clinical attachment loss of 3 mm at two interproximal locations. Nutritional analysis was used to estimate daily calcium and vitamin D intakes (from food and supplements). Results: Supplement users exhibited shallower probing depths, fewer bleeding sites, lower gingival index values, fewer furcation involvements, less attachment loss, and less alveolar crest height loss than those who did not take vitamin D and calcium supplements. The differences in clinical indicators were borderline significant (P=0.08), according to the repeated-measures analysis. Conclusion: In these subjects receiving periodontal maintenance therapy, there was a trend for better periodontal health with intake of vitamin D and calcium supplementation. More expanded longitudinal studies are required to determine the potential of this relationship.