Zinc is an essential nutrient that participates in many biological processes, modulating the activity of more than 300 enzymes and 2,000 transcription factors. It plays critical roles in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. A recent study found that moderate zinc intake reduces the risk of hypertension; however, higher intakes markedly increase the risk.

The study involved more than 12,000 participants who did not have hypertension at their enrollment. Researchers assessed the participants' dietary intake using three consecutive 24-hour dietary recalls combined with a household food inventory. They tracked participants for about six years to identify new cases of hypertension, defined as having a systolic blood pressure of 140 mmHg or higher, a diastolic blood pressure of 90 mmHg or higher, being diagnosed by a physician, or being under antihypertensive treatment.

They found that the relationship between zinc intake and hypertension risk demonstrated a J-shaped curve – that is, the risk fell with moderate intake but dramatically increased with higher intake. Moderate zinc intake (up to 10.9 milligrams daily) decreased the risk of developing hypertension by 7 percent. However, when consuming 10.9 milligrams or more daily, each additional milligram of zinc increased the risk of hypertension by 14 percent.

These findings suggest that moderate zinc intake may help reduce the risk of developing hypertension, but excessive intake markedly increases the risk. Zinc plays a crucial role in maintaining healthy blood pressure by supporting the activity of nitric oxide synthase, an enzyme that regulates blood flow and vasodilation. Zinc deficiency impairs the vasodilatory response and can reduce taste sensitivity, potentially increasing salt intake and elevating blood pressure. Learn more about zinc in our comprehensive overview article.

• Read study abstract.