J-shaped association between dietary zinc intake and new-onset hypertension: a nationwide cohort study in China

Hypertension is a leading cause of cardiovascular disease and premature death, affecting over a billion individuals worldwide. Zinc is the second most abundant transition metal in the body and plays a crucial role in various biological functions. Previous studies have shown inconsistent results regarding the association between zinc intake and hypertension.

Panpan He et al., at Division of Nephrology, Nanfang Hospital, Southern Medical University, China, conducted a study that focuses on J-shaped association between dietary zinc intake and new-onset hypertension.

The study used data from the China Health and Nutrition Survey (CHNS), a national, prospective open-cohort study. Participants were excluded if they were pregnant, under 18 years old, or had missing blood pressure data. Dietary intake was recorded using 24-hour recalls and converted into nutrient intake using Chinese food composition tables. New-onset hypertension was defined based on systolic and diastolic blood pressure measurements or antihypertensive treatment.

A total of 12,177 participants were included in the final analysis. The study found a J-shaped relationship between dietary zinc intake and the risk of new-onset hypertension, with an inflection point at 10.9 mg/day. The risk of hypertension decreased with increasing zinc intake below 10.9 mg/day and increased with intake above this threshold. The study also found that the minimal risk of hypertension was at dietary zinc intake levels of 10.0 to 12.2 mg/day.

The study provides new insights into the relationship between dietary zinc intake and hypertension. The observed J-shaped relationship suggests that both low and high zinc intake may be associated with an increased risk of hypertension. The study's findings may have implications for maintaining optimal dietary zinc intake levels for the prevention of hypertension.

This study contributes to the understanding of the role of dietary zinc in hypertension and could inform dietary guidelines and public health strategies for the prevention of hypertension.