Many people get their zinc (in the western diet) by eating red meat, seafood or fortified foods (like breakfast cereals). Some other good food sources of zinc are beans & nuts, but these foods have phytates which inhibit the body's ability to absorb the zinc that the beans & nuts naturally have.
All in all, zinc supplements are man made from zinc and not derived from a vegetable or food. Zinc sulfate is produced by treating virtually any zinc-containing material (metal, minerals, oxides) with sulfuric acid. Zinc sulfate is considered GRAS by the FDA and was picked for our product because it has the highest reported absorption rate at 71% (compared, for example, to zinc citrate at 61.3%, zinc gluconate at 60.9% or zinc oxide at 49.9%).1
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