The adverse association of animal zinc intake with cardio-cerebrovascular and metabolic risk factors.

ABSTRACT

Background: The effect of zinc intake on cardio-cerebrovascular and metabolic diseases has always been controversial. Aims: We hoped to evaluate the associations of the daily dietary estimate (DDE) of zinc intake with cardio-cerebrovascular and metabolic risk factors. Methods: Baseline data from the Study of Women's Health Across the Nation (SWAN) were obtained. Multivariable linear regression analysis was used to examine associations of the DDE of zinc intake with cardio-cerebrovascular and metabolic risk factors. Results: The smooth curve demonstrated positive associations of the DDE of animal zinc intake with low-density lipoprotein-cholesterol (LDL-C), triglycerides, total cholesterol, fasting blood glucose, insulin, systolic blood pressure (BP) and diastolic BP and an inverse association of the DDE of animal zinc intake with high-density lipoprotein-cholesterol (HDL-C). Consistently, multivariable linear regression models also showed that an increased DDE of animal zinc intake was closely related to a higher risk of cardio-cerebrovascular and metabolic risk factors [systolic BP 0.37 (0.13, 0.61); diastolic BP 0.17 (0.02, 0.33); fasting blood glucose 1.13 (0.67, 1.59); insulin 0.26 (0.05, 0.47); LDL-C 0.82 (0.34, 1.29), triglycerides 1.65 (0.75, 2.55), total cholesterol 0.91 (0.38, 1.43) and HDL-C -0.24 (-0.45, -0.03)] when age, race/ethnicity, total family income, smoking status, alcohol consumption and menopausal status were controlled for. Importantly, stratified analysis supported that the independent associations between the DDE of animal zinc intake and risk factors for cardio-cerebrovascular and metabolic diseases were hardly affected by age and body mass index (BMI). Conclusion: We found that an increased DDE of animal zinc intake was associated with higher cardiovascular and metabolic risks among middle-aged women, which did not support the benefit of zinc intake in reducing cardiovascular and metabolic risks. The association seems to be incongruous with the anti-inflammation and antioxidation physiological functions of zinc. Thus, additional well-designed and prospective studies are needed to confirm this association.