Zinc (as Citrate): What the Science Says
The prostate accumulates more zinc than any other soft tissue in the body, and lower zinc levels are consistently observed in diseased prostate tissue. That association is well documented.
What is far less established is whether supplementing zinc reverses it. The observed link may be a consequence of the disease rather than a cause. The frequently cited testosterone study was small and conducted in men who were already zinc deficient, so the result does not generalise to men with adequate intake.
One point worth knowing: some large cohort studies have associated very high long-term zinc intake, above 100mg daily, with increased prostate cancer risk. The 12mg here is a normal dietary dose and well within safe limits, but stacking multiple zinc-containing supplements is not a good idea.

