What do systematic reviews say?

Zinc vs placebo

Zinc showed no clear difference in progression to visual loss (loss of 3 or more lines on logMAR chart) compared with placebo (moderate certainty).

• Antioxidant vitamin and mineral supplements for slowing the progression of age‐related macular degeneration 2023 · Cochrane Headline outcomes only
  OR 0.87 [0.75, 1]
  2 studies · 3791 participants
  Moderate