Association of natural teeth, dietary diversity, and nutritional status in elderly nursing home residents

Objective Tooth loss in older adults was associated with an elevated risk of malnutrition, which may be compounded by limited dietary diversity. This study aimed to assess the associations between the number of natural teeth, dietary diversity (DD), and nutritional status among elderly nursing home residents. Materials and methods This cross-sectional study involved 1,710 nursing home residents aged ≥60 years from 26 facilities. Number of natural teeth, dietary diversity score (DDS), and nutritional status were assessed. Logistic regression and mediation analysis were used to examine the associations between the number of natural teeth, DD, and nutritional status, and the mediating role of DD. Results Participants had a mean age of 83.28 ± 8.66 years. After adjusting for confounding variables, compared with participants with 0 natural teeth, those with ≥20 natural teeth showed a positive correlation with normal nutritional status (Odds Ratio OR = 4.29, 95% Confidence Interval CI:2.26–6.15). Additionally, compared with those with a DDS of ≤5, a DDS of 8 was associated with better nutritional status (OR = 2.11, 95%CI: 1.17–3.82). DD mediated the relationship between the number of natural teeth and nutritional status ( β = 0.0075, 95%CI: 0.0041–0.0114). Conclusion Present study indicated that older adults in nursing homes with a greater number of natural teeth tended to have better nutritional status. DD played a mediating role in this association, indirectly influencing the nutritional status of the elderly. These findings highlight the critical significance of the number of natural teeth in maintaining favorable nutritional status among the elderly. Meanwhile, they suggest that DD should be incorporated into the scope of attention when focusing on the nutritional status of the elderly.