Zinc is very tricky. Hard to absorb. But taking too much can do more harm than good. It becomes an immunosuppressent/sp above an optimal amount. Not good.
If you want to do it right. You need a serum blood test.
Take a reasonable amount- say 30-40mg five days a week for a month.
Then get a lab test.
If you live near a city you probably have access to a Labcorps lab.
So go to the Life Extension foundation and google labtests. Find zinc. Might have to just look on the A-Z index there. Order the test.
Go to Labcorp, take the paperwork that Life Extension foundation sent you, give it to them, have the blood drawn. Wait a couple days and you will get an email from Labcorp with your test results. With ranges shown. And where you are on it. Cost = $26.00 right now, anyway.
Adjust your zinc intake as needed -up or down- if you have made a large adjustment then retest again at some later date to see where you are now.
If you don't live near a Labcorp lab they have some other process which is to send a test kit and you go to your local lab and have the blood drawn and then send it to Labcorp. Or something like that. Anyway, there is a process there that will work for you too.
You could be taking a pantload of zinc and be wayy over an optimal amount, or you could be taking a pantload and getting very little absorption and need to take even more. You don't know without a blood test. I mean if your zinc level is critical to you in this covid time that is how to find out where you are really at. You go do all this through your local doctor too but it will cost you a lot more and you will have to explain all sorts of stuff that will just slow you down or cause you to act as though you need their agreement on something or not. You don't.