Weight Loss and Number of Present Teeth in Community-Dwelling Japanese Older Adults: A Cross-Sectional Study in Niigata

Background and objectives: Weight loss is a critical health issue among the older population. This study aimed to explore the association between weight loss and oral health in older adults.

Methods: We used cross-sectional data from the Uonuma Chronic Kidney Disease Cohort Study. The binary logistic regression models were fitted to estimate the relationship between weight loss and independent variables including the number of teeth present.

Results: The participants included 1656 females and 1625 males. There were 1217 females (73.4%) and 1236 males (76.0%) with normal BMI (18.5 ≤ BMI < 25) in the previous year. Weight loss was determined over a 12-month period. Individuals with normal BMI in previous year, and those with weight loss (≥ 5%) or those whom maintained a stable weight were further analysed. The regression analysis (model 3, fully adjusted) showed that females with 0 and 1-10 teeth present had a higher likelihood of losing weight (OR = 4.07; 95% CI = 1.85-8.93, OR = 2.33; 95% CI = 1.24-4.39) compared with those with 20 or more teeth. Current smokers had a higher likelihood of losing weight (OR = 3.15; 95% CI = 1.01-9.76) than lifelong abstainers. Among males, both current and previous smokers showed a higher likelihood of losing weight (OR = 4.94; 95%CI = 1.76-13.8, OR = 3.35; 95% CI = 1.29-8.68) than those who never smoked.

Conclusions: This study indicates that the number of teeth and smoking are both linked to weight loss in females. However, in males, the association between the number of teeth and weight loss may be compromised due to the high prevalence of smoking in this group.