According to Earl Mindell in his book Vitamin Bible, “Zinc acts like a traffic policeman, directing and overseeing the efficient flow of body processes (and) the maintenance of enzyme systems and cells.” So basically, it is involved in most bodily functions.
Zinc is a regulator of the immune system, ensuring that cells for identifying and killing microbes, viruses and cancerous cells are in good working order. Zinc also speeds wound healing and is used for the healing of burns and surgical incisions.
Studies have shown that zinc can protect against flu and colds. In a study published in the American Journal of Clinical Nutrition, seniors who took 45mg of zinc had fewer infections than those who took a placebo.
Just be careful – zinc can interfere with the absorption of copper in the long term. So if you are taking zinc for longer than a month, make sure to take 2 to 3 mg of copper a day.