Zinc is an essential element to human nutrition and the second most abundant trace mineral present in the body. Zinc plays a role in numerous biological functions. Zinc enzymes are involved in the production of energy, the synthesis of DNA and RNA, the metabolism of nucleic acid and proteins, as well as the maintenance of membrane structure through the stabilization of thiol groups and phospholipids. Zinc is necessary for many immune system functions as well as antioxidant activities, such as protection of membranes from oxidation. Zinc is important for normal growth and development, reproduction, blood clotting, thyroid hormone function, and many other processes. Zinc can be found in high concentrations in meat, seafood, dairy products, nuts, legumes, and whole grains.
The absorption and effectiveness of zinc or the following drugs may be challenged when zinc is combined with captopril, chlorthalidone, cisplatin, fluoroquinolones, penicillamine, potassium-sparing diuretics, tetracyclines, and thiazide diuretics. It is not recommended that zinc be combined with copper, IP-6, or iron. As with any drug or supplement, consult a health care professional before use.
For the most part, zinc in doses up to 30 mg daily is well tolerated, although higher doses can be recommended. Occasional reactions and high doses (>150-300 mg daily) may bring adverse effects such as nausea, vomiting, headache, drowsiness, metallic taste, and gastrointestinal upset.