Table 2.

Odds ratios (ORs) (95% CI) for metabolic syndrome and its components according to the quartiles of total iron intake (mg/day) among all participants in the SDHS 2012–2013.

	Quartiles of Dietary Iron Intake, ORs (95% CI)
	Q1	Q2	Q3	Q4	p-Value for Trend 1
Total Iron Intake (mg/day)	<12.72	(12.72–16.50)	(16.50–21.88)	≥21.88
n	776	773	776	774
Metabolic syndrome
Crude model	Reference	1.12(0.88,1.42)	1.24(0.98,1.57)	1.17(0.92,1.48)	0.335
Adjusted model 2	Reference	1.37(1.06,1.78) *	1.47(1.11,1.94) **	1.59(1.15,2.20) **	0.022
				p-Value for interaction 3 = 0.060
Metabolic syndrome components
Elevated blood pressure
Crude model	Reference	0.95(0.79,1.13)	1.19(1.00,1.42) *	1.07(0.89,1.27)	0.063
Adjusted model 2	Reference	1.14(0.92,1.41)	1.33(1.06,1.66) *	1.21(0.93,1.57)	0.100
Elevated waist circumference
Crude model	Reference	1.07(0.89,1.29)	1.09(0.91,1.32)	1.00(0.83,1.21)	0.691
Adjusted model 2	Reference	1.25(1.01,1.53) *	1.29(1.04,1.60) *	1.25(0.96,1.61)	0.096
Elevated fasting glucose
Crude model	Reference	1.03(0.83,1.27)	1.16(0.94,1.42)	1.12(0.91,1.38)	0.458
Adjusted model 2	Reference	1.18(0.94,1.49)	1.25(0.98,1.60)	1.33(1.00,1.77)	0.221
Elevated triglycerides
Crude model	Reference	1.17(0.95,1.43)	1.46(1.20,1.77) **	1.34(1.10,1.64) **	0.001
Adjusted model 2	Reference	1.14(0.92,1.42)	1.37(1.09,1.72) **	1.31(1.00,1.71) *	0.047
Reduced HDL-C 4
Crude model	Reference	1.09(0.86,1.38)	1.11(0.87,1.41)	0.91(0.71,1.16)	0.348
Adjusted model 2	Reference	1.27(0.98,1.65)	1.42(1.08,1.87) *	1.31(0.94,1.83)	0.088

* p < 0.05, ** p < 0.001. ¹ The p-value for the trend was examined using the medians in each quartile of dietary iron intake. ² The models were adjusted for age, sex, income, physical activity level, intentional physical exercise, smoking status, alcohol use and dietary total energy intake. ³ The p-value for the interaction was tested for the quartiles of dietary iron intake by gender. ⁴ HDL-C: high-density lipoprotein-cholesterol.