Figure 1.

Relationship between dietary Cu/Zn ratio and hazard ratios of Type 2 diabetes fitted with restricted cubic splines (three knots placed at the 5th, 10th, and 50th percentiles). Risk estimates were adjusted for age, family history of diabetes, smoking status, physical activity, educational level, hypercholesterolemia, hypertension, body mass index, and total energy. Reference value for hazard ratios: minimum Cu/Zn ratio (0.054); the solid blue line represents the hazard ratio; the dashed lines the lower and upper 95% confidence interval. p_overall = 0.0194; p_NONLIN = 0.0173 and the solid green line represents the reference line of hazard ratio equal 1.