Every published case of zinc overload had copper running low
Across 37 cases, doses started around 50 mg a day and ran for weeks to years. The blood picture looked so like a marrow cancer that patients were often diagnosed with one first.
What the study found
Copper was low in all 37 published cases of zinc overload
It makes a blood picture close enough to a bone marrow cancer that patients were often diagnosed with one first. Doses started around 50 mg a day and ran for weeks to years. Stopping zinc and replacing copper restored blood counts; nerve damage recovered more slowly, sometimes not fully.
The caveat · No rate, only 37 striking cases
Thirty-seven cases gathered over 53 years have no denominator, so nothing here says how likely this is at any dose, and case reports get published because they are striking. The zinc came from denture adhesive cream and swallowed coins as well as supplements, so not every dose in that range is a supplement dose. A single case at 50 mg a day is not evidence that 50 mg a day is generally unsafe.
What we don't know
Thirty-seven cases gathered over 53 years have no denominator, so nothing here says how likely this is at any dose, and case reports get published because they are striking. The zinc came from denture adhesive cream and swallowed coins as well as supplements, so not every dose in that range is a supplement dose. A single case at 50 mg a day is not evidence that 50 mg a day is generally unsafe.