After refractive surgery, the doctor suggested taking 1000mg of vitamin C daily to help minimize scarring. When I went to pick up the vitamins, I also noticed that there was a supplement claiming to be designed to support eye health that also included vitamin C. Specifically, it has:

  • 250mg vitamin C
  • 200 IU vitamin E
  • 40mg zinc (as 50mg zinc oxide)
  • 1mg copper

...per tablet. The recommended dosage is 1 tablet/day, and I'd have to take 4 times that amount to get 1000mg of vitamin C/day.

From what I can determine 800 IU of vitamin E and 4 mg copper are within safe/tolerable limits, however 160mg of elemental zinc is quite high. There are only a few conditions I can find where dosages around that level are recommended for therapeutic purposes:

  • Acne (for up to 8 weeks)
  • Wilson's disease (ongoing)
  • Macular degeneration (ongoing)

So my question is, what's the safe maximum dosage of zinc over a course of 4-6 weeks? From what I can find, it seems like the biggest risk is that high dosages of zinc lead to copper deficiency (hence why it's used to as a treatment for Wilson's disease). Does it therefore follow that 160mg/day should be okay as long as it's supplemented with some extra copper and not continued on a long-term basis?

1 Answer 1


You are right, too much zinc could be harmfull but in your case you are at the upper limit.

Zinc supplements should not exceed 40mg per day for adults. You find all details here: https://ods.od.nih.gov/factsheets/Zinc-Consumer/#h8

Hope this helps.

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