Norm depends on age
The human body contains regarding 2-3 grams of zinc. Values may vary depending on gender, age, chronic diseases, characteristics of the functioning of the intestine, namely the absorption capacity of the mucous membrane.
The maximum allowable intake of zinc per day is 25 mg, on average, the average person needs regarding 15 mg daily. An overdose can be caused by the consumption of various zinc compounds in excess of 150 mg, it is accompanied by bowel disorders, nausea, vomiting, headache. But getting a similar problem if you simply consume foods rich in zinc is impossible. An overdose can be obtained by taking high doses of zinc supplements for a sufficiently long time.
And one more thing: with excessive intake of zinc, the content of copper in the body may suffer, and this is already fraught with problems with the formation of new blood cells, malfunctions in metabolism.