Abstract Body (Do not enter title and authors here): Background: Zinc is an essential trace element that can affect cardiovascular health through a variety of pathways including influencing vascular endothelial cell stability and signaling processes. Dietary intake is the main source of zinc in humans. Epidemiologic studies on the association between dietary zinc and cardiovascular disease remain scarce, especially in China.
Aims: To investigate the associations of dietary zinc intake with the risk of cardiovascular disease and mortality in Chinese adults.
Methods: Based on the Prospective Urban and Rural Epidemiology in China (PURE-China) study, we included people aged 35-70 years from 12 provinces in China. The daily dietary intake was recorded by a semi-quantitative food frequency questionnaire designed for Chinese people, and the daily dietary zinc intake was obtained based on the nutrient content of each food provided in the Chinese Food Composition Table (2002). Cox frailty proportional hazards models were developed to evaluate the association between dietary zinc intake with mortality and major cardiovascular diseases.
Results: A total of 41 310 participants were included in the study after excluding participants with incomplete information, cardiovascular disease at baseline, and no follow-up information. The mean dietary zinc intake was 14.07±6.10 mg/d and the median level was 12.98mg/d. After 11.9 years of follow-up, 3 209 (7.8%) developed new cardiovascular diseases, 5.3% (2 170) died during follow-up, 714 (1.7%) died from cardiovascular diseases and 4 594 (11.1%) had a composite endpoint event. Compared with those in the second quartile of dietary zinc intake, those in the fourth quartile had a higher risk of all-cause mortality (HR[95%CI]: 1.20 [1.01-1.44]), stroke (HR[95%CI]: 1.25 [1.05-1.48)), and composite outcomes (HR[95%CI]:1.17 [1.03-1.32]). Those in the fourth quartile had a higher risk of major cardiovascular disease (HR[95% CI]:1.17 [1.03-1.32]) compared with those in the first quartile of dietary zinc intake.
Conclusions: Excessive dietary zinc intake in the Chinese population may be associated with an elevated risk of cardiovascular disease and death. Further studies should be conducted to clarify the upper limit of dietary zinc intake.