The effects of bodybuilding and protein supplements on periodontal tissues have not yet been evaluated. The present study aimed to examine the periodontal status and interleukin (IL)-1 beta, apoptosis-associated speck-like protein containing C-terminal caspase-recruitment domain (ASC), and caspase 1 (CASP1) gene expression levels of body builders compared with those of controls. Twentyfive bodybuilders with gingivitis (BB-G) who used protein powder supplements were compared with 25 nonexercising males with (G) and 25 without (H) gingivitis. Saliva, gingival crevicular fluid (GCF), and serum were collected for gene expression analysis. Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP) were recorded. GI and BOP were higher in group BB-G and G than in group H (P < 0.01), but PI, PD, and CAL were similar between groups (P > 0.05). In GCF, CASP1, ASC, and IL-1 beta expression were upregulated in group G compared with groups BB-G and H (P < 0.01). In addition, ASC (P < 0.05) and IL-1 beta (P < 0.01) were downregulated in group BB-G compared with group H. CASP1, IL-1 beta (P < 0.01), and ASC in the saliva were downregulated in group BB-G compared with groups H and G (P < 0.05). CASP1, IL-1 beta, and ASC may play a role in the pathogenesis of gingivitis. Bodybuilding and supplement usage may decrease gingival inflammation by downregulating CASP1, and ASC.