Zinc, a trace mineral, is an essential part of a healthy diet. We use it in our cells in enzymes and proteins, as transcription factors (used in the protein production and gene expression) and catalysts.
Zinc is necessary for our immune function, since it is integral to white blood cell function and production. Zinc has been linked to lowered levels and severity of acne (in part caused by Propionibacterium acnes, a bacteria), and this may be due in part to zinc’s part in immunity. However, the studies in this area have not reached consensus.
Zinc interacts with vitamin A, most notably by splitting retinol into retinal, a molecule in the protein rhodopsin which is responsible for sight. It may interact with folic acid. However, it isn’t all just sunshine and unicorns: zinc can decrease copper bioavailability. Plus, excess iron, calcium, and phytates (from phytic acid) can lower zinc’s bioavailability.
Because phytic acid can bind to zinc rendering it unable to be absorbed and animal foods providing some of the highest concentrations of zinc, vegetarians must be especially careful about this mineral. Vegetarians may need up to 1.50 times as much zinc as the standard omnivore.
NIH Office of Dietary Supplements Zinc Fact Sheet for Health Professionals.
Jane Higdon, Ph.D. (2003). Zinc. Linus Pauling Institute, Oregon State University. Updated in 2013 by Emily Ho, Ph.D.