Zinc is called an “essential trace element” because it's necessary for numerous chemical processes that take place within a cell. It's required for the activity of approximately 100 enzymes and it plays a role in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence and is required for proper sense of taste and smell. To maintain a steady state of zinc, daily intake is required because our bodies don’t have a specialized system for storing zinc.
Let's talk about six health issues when supplemental zinc may be appropriate.
Immune Function and the Common Cold
The relationship between zinc and the immune system is complex since there are four different ways zinc influences the immune system. Although technical, zinc does indeed help the immune system fight off invading bacteria and viruses.
There is reliable and relatively consistent data showing zinc is most effective at treating the common cold when taken within 24 hours of the onset of symptoms.
Zinc lozenges used at the first sign of a cold have been shown to help stop the virus and shorten the illness.
Lozenges containing zinc gluconate, zinc gluconate-glycine, and, in most trials, zinc acetate have been effective; most other forms of zinc and lozenges flavored with citric acid, tartaric acid, sorbitol, or mannitol have been ineffective.
For the alleviation of cold symptoms, lozenges providing 13 to 25 mg of zinc (as zinc gluconate, zinc gluconate-glycine, or zinc acetate) are used every two hours while awake but only for several days. Remember, the best effect is obtained when lozenges are used at the first sign of a cold.
Long ago, during my first dietitian job at a hospital, I handled the nutrition piece within the hospital’s wound care clinic. I learned a lot about the value of eating specific nutrients to help heal these gnarly open wounds and sores. Zinc was one of those specific nutrients I often suggested the patients take. It’s important in the formation of collagen, a critical component in healing wound, and can enhance the wound-healing process.
Studies in developing countries found zinc may reduce the severity and duration of diarrhea in poorly nourished children, especially those with low zinc levels.
There’s reliable and relatively consistent information showing a zinc deficiency leads to reduced numbers of sperm and impotence in men. Taking zinc may correct this problem and improve sperm quality. The ideal amount of supplemental zinc remains unknown, but some doctors recommend 30 mg two times per day. Long-term zinc supplementation requires 1–2 mg of copper per day to prevent copper deficiency.
Age-related Macular Degeneration (AMD)
This eye disease gradually causes vision loss. Research suggests zinc might help keep early age-related macular degeneration from worsening into advanced AMD. More research is needed before doctors can recommend zinc supplements for AMD, but people who have or are developing it might want to talk to their doctor about taking zinc.
The healing process of stomach ulcers may be enhanced through treatment with zinc, although more studies are needed to more clearly determine its effects. Most studies report few or no side effects associated with its use.
Recommended Dietary Allowances for Zinc
As suggested by National Institutes of Health; Office of Dietary Supplements:
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
Prasad AS, Cossack ZT. Zinc supplementation and growth in sickle cell disease. Ann Intern Med 1984;100:367-71.
National Institutes of Health; Office of Dietary Supplements. Zinc Fact Sheet for Consumers.
Recommended Daily Allowances for Zinc chart: US Dept of Health & Human Services: National Institutes of Health/Office of Dietary Supplements, found here: http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/#h4