Table 3.

Threshold effect analysis of relationship of zinc intake and Helicobacter pylori seropositivity.

	Zinc
	Adjusted OR_95CI	p value
Two model
Zinc intake < 24.925	0.982 (0.965 ~ 0.999)	0.0346
Zinc intake ≥ 24.925	1.026 (0.968 ~ 1.087)	0.3868
Non-linear test 1		0.048
Non-linear test 2		0.005

Adjusted for age, gender, marital status, poverty-income ratio, education, body mass index, cardiovascular disease (heartfailure, coronary heart disease, angina, and heart attack), smoking, alcohol, diabetes, and serum indicators (CRP, albumin, total cholesterol, and creatinine). Hp, Helicobacter pylori; CRP, C-reactive protein; CI, confidence interval; OR, odds ratios; Ref, reference.