Background: Japan’s rapidly aging population has increased the urgency of addressing frailty among older adults. Oral hypofunction and malnutrition are recognized as key contributors to frailty, and both are considered reversible through early interventions. However, little is known about the effectiveness of integrating nutritional guidance and oral function training in community dental clinics. This study aimed to examine the association between dietary variety, oral function, and body composition among outpatients aged 50 years and older, and to evaluate the effects of targeted interventions over a 1-year period. Methods: A total of 74 outpatients (mean age 72.3±9.6 years) were assessed at baseline and after 1 year. Dietary variety was evaluated using the Dietary Variety Score (DVS), and oral function was assessed using seven standardized parameters. Body composition, including weight, body fat percentage, and muscle mass, was assessed using a bioelectrical impedance analyzer. Based on DVS results, registered dietitians provided nutritional counseling, while dental hygienists delivered tailored oral function training. Statistical analyses included the Wilcoxon signed-rank and McNemar’s tests. Results: Significant improvements were observed in eight of the ten DVS food groups, resulting in a higher total DVS score. Tongue coating index and tongue pressure also improved significantly, and the prevalence of oral hypofunction declined. No significant changes were found in body composition. Conclusion Integrating nutritional guidance and oral function training in a community dental setting improved dietary variety and oral function in older adults. These findings suggest that multidisciplinary care in community dental clinics may contribute to health promotion and frailty prevention.

The purpose of this study was to investigate the effects of Lactobacillus gasseri OLL2809 (MG2809) intake on salivary secretory immunoglobulin A (SIgA) secretion and incidence of upper-respiratory tract infection (URTI) symptoms among college rugby athletes. Sixty-seven subjects were assigned to a MG2809 group (n = 33) or a placebo group (n = 34) using a double-blind procedure. Each subject took MG2809 or placebo tablets for 9 weeks. Resting saliva samples were collected before (0 week) and after 2, 4, 6, 8, and 9 weeks of the MG2809 intakes. A log of URTI symptoms was kept every day during the study period. Our results showed that salivary SIgA level was significantly increased at 6 weeks in the MG2809 group (p < 0.05), although the placebo group did not show significant change. The duration of URTI symptoms episode in the MG2809 group was significantly shorter than that in the placebo (p < 0.05). These results suggest that regular intake of MG2809 may enhance oral immune function mediated by SIgA and reduce the risk of URTI in athletes.