Medically Reviewed by Melinda Ratini, MS, DO on April 06, 2022

Zinc is a mineral that's important to the body in many ways. Zinc keeps the immune system strong, helps heal wounds, and supports normal growth.

Zinc deficiency occurs frequently in developing countries. Zinc deficiency in the U.S. is rare, because most diets provide more than the recommended dietary allowance.

Zinc has become a popular treatment for the common cold. Some studies have found that zinc lozenges may reduce the duration of cold, perhaps by a day or so, and may reduce the number of upper respiratory infections.

Zinc helps fight infection and heal wounds. However, if you already have enough zinc from your diet, it is not clear that getting even more -- from supplements -- has a benefit.

Topical zinc is used to treat diaper rash and skin irritations. Zinc has also been shown to help with ulcers, ADHD, acne, sickle cell anemia, and other conditions.

In addition, zinc has also been studied as a treatment for herpes, high cholesterol, rheumatoid arthritis, HIV, and more. However, the evidence of zinc's benefit for these conditions is inconclusive.

Zinc may be part of an effective treatment for age-related macular degeneration, but more proof is needed.

Health care providers may recommend zinc supplements for people who have zinc deficiencies. Strict vegetarians, alcohol abusers, and people who have a poor diet are at higher risk for zinc deficiency. So are those with certain digestive problems, such as Crohn's disease.

The recommended dietary allowance (RDA) includes the zinc you get from both the food you eat and any supplements you take.


Recommended Dietary Allowance (RDA) of Zinc


7 months to 3 years

3 mg/day

4-8 years

5 mg/day

9-13 years

8 mg/day


14-18 years

9 mg/day

19 years and up

8 mg/day


14-18 years: 12 mg/day
19 years and over: 11 mg/day


14-18 years: 13 mg/day
19 years and over: 12 mg/day


14 years and up

11 mg/day

The tolerable upper intake level (UL) of a supplement is the highest amount that most people can take safely. Never take more unless your health care provider says so. Keep in mind that this upper limit includes the zinc you get from foods and supplements.

(Children & Adults)

Tolerable Upper Intake Level (UL) of Zinc

0-6 months

4 mg/day

7-12 months

5 mg/day

1-3 years

7 mg/day

4-8 years

12 mg/day

9-13 years

23 mg/day

14-18 years

34 mg/day

19 years and up

40 mg/day

To avoid irritating the stomach, take zinc with food. For the common cold, zinc lozenges are typically taken every 2 to 3 hours within 48 hours of the start of symptoms. Then, take the zinc lozenges every 2 to 3 hours while awake until the symptoms go away. There are zinc supplements in pill and liquid form. 

Good food sources of zinc are:

  • Red meat
  • Poultry
  • Oysters
  • Fortified cereals
  • Whole grains
  • Beans and nuts
  • Side effects. Zinc supplements can irritate the stomach and mouth. Zinc lozenges can alter your sense of smell and taste for a few days. If taken long-term, zinc lozenges may lower copper levels in the body. Zinc nasal sprays have been associated with a loss of smell, which may be permanent.
  • Interactions. Zinc may interact with some medicines such as birth control pills and some antibiotics. Zinc can also interact with other supplements, such as calcium, magnesium, copper, and iron. If you take daily medicine or supplements, ask your healthcare provider about taking zinc.
  • Risks. People who are allergic to zinc, have HIV, or have hemochromatosis should not take zinc supplements without talking to their doctor first. Too much zinc can cause fever, cough, nausea, reduced immune function, mineral imbalances, cholesterol changes, and other issues. In pregnant women, high doses may harm the fetus.

Show Sources

Longe, J., ed. The Gale Encyclopedia of Alternative Medicine, second edition, 2004.
Linus Pauling Institute at Oregon State University: "Micronutrient Information Center: Zinc."
Natural Standard monograph: "Zinc."
Office of Dietary Supplements: "Facts about Dietary Supplements: Zinc."
Archives of Ophthalmology
: "A Randomized, Placebo-Controlled, Clinical Trial of High-Dose Supplementation With Vitamins C and E, Beta Carotene, and Zinc for Age-Related Macular Degeneration and Vision Loss."

Natural Medicines Comprehensive Database: "Zinc."

Institutes of Medicine: "Dietary Reference Intakes: Elements."

Natural Standard: "Zinc."

The Journal of Family Practice. "Zinc for the common cold—not if, but when." 

Cochrane Database Syst Rev:"Zinc for the common cold" and "Zinc supplementation for the prevention of pneumonia in children aged 2 months to 59 months."

Canadian Medical Association Journal: "Prevention and treatment of the common cold: making sense of the evidence."

Clin Respir J. "Efficacy of zinc given as an adjunct to the treatment of severe pneumonia: A meta-analysis of randomized, double-blind and placebo-controlled trials."


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