Abstract
OBJECTIVE: Previous studies have extensively explored the association between body mass index (BMI) and the risk of diabetes. However, evidence regarding the relationship between body fat percentage (BF%) and diabetes risk remained limited. This study aimed to investigate the association between BF% and the risk of diabetes among Chinese adults. METHODS: We conducted a retrospective cohort study involving 211,833 Chinese adults who underwent health evaluations from 2010 to 2016. The relationship between baseline BF% and diabetes risk was analyzed using Cox proportional hazards regression models. Additionally, cubic spline functions and smooth curve fitting were used to examine the nonlinear relationship between BF% and diabetes onset. Sensitivity and subgroup analyses were performed to validate the robustness of our findings. RESULTS: After adjusting for the variables, our analysis demonstrated that a 1% increase in BF% is associated with a 1.04-fold higher risk of diabetes (HR: 1.04, 95% CI: 1.04-1.05, p < 0.0001). Diabetes risk progressively increased across BF% quartiles (Q1 to Q4), with Q4 showing a significantly higher risk than Q1 (adjusted HR: 2.72, 95% CI: 2.19-3.37). Furthermore, a nonlinear association between BF% and diabetes risk was identified, with a critical inflection point at 25.09%. Below this threshold, the HR was 1.17 (95% CI: 1.13-1.21), while above it, the HR was 1.02 (95% CI: 1.02-1.03). The subgroup analysis and sensitivity analysis demonstrated the robustness of these results. CONCLUSION: This study indicates a positive, nonlinear relationship between BF% and diabetes risk in Chinese adults. Reducing BF% below the identified threshold could significantly lower the risk of developing diabetes.