Zinc is necessary for the functioning of more than 300 different enzymes and plays a vital role in a large number of biological processes. Zinc is a cofactor for the antioxidant enzyme superoxide dismutase (SOD) and is in a number of enzymatic reactions involved in carbohydrate and protein metabolism.

Its immune-enhancing activities include regulation of T lymphocytes, CD4 cells, natural killer cells, and interleukin-2. In addition, it has been claimed that zinc possesses antiviral activity. Zinc is necessary for the maturation of sperm and normal fetal development. It is involved in sensory perception (taste, smell, and vision) and controls the release of stored vitamin A from the liver. In the endocrine system, zinc has been shown to regulate insulin activity and promote the conversion thyroid hormones thyroxine to triiodothyronine.

Zinc has been used since ancient Egyptian times to enhance wound healing, although the usefulness of this approach is only partially confirmed by clinical data today. In available research, it has been shown to play a role in wound healing, especially following burns or surgical incisions. Based on available scientific evidence, zinc may be effective for the treatment or management of a number of conditions, including diarrhea in malnourished children, skin conditions (such as acne vulgaris, eczema, and psoriasis), gastric ulcers, attention-deficit hyperactivity disorder (ADHD), immune disorders, sickle cell anemia, leg ulcers, infertility, Wilson’s disease, herpes, taste or smell disorders, diabetes, and diabetic neuropathy. Zinc has also gained popularity for its use in the prevention of the common cold.

The role of zinc is controversial in some cases, as either the results of published studies provide contradictory information and/or the methodological quality of the studies does not allow for a confident conclusion regarding the role of zinc in the diseases in question.