Zinc is an essential mineral for immune function, DNA synthesis, and metabolism, best obtained through a balanced diet.
Supplements may shorten the common cold's duration by about two days but do not prevent illness or significantly boost immunity in healthy individuals.
Evidence suggests that zinc supplementation does not reliably improve male fertility or sperm quality in larger, modern clinical trials.
Excessive intake can cause side effects like nausea and long-term health issues, including copper deficiency and weakened immunity.