Dietary Supplement Fact Sheet: Zinc
This fact sheet by the Office of Dietary Supplements provides information that should not take the place of medical advice. We encourage you to talk to your healthcare providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health.What is zinc and what does it do?
Zinc is a nutrient that people need to stay healthy. Zinc is found in cells throughout the body. It helps theimmune system fight off invading bacteria and viruses. The body also needs zinc to make proteins and DNA, the genetic material in all cells. During pregnancy, infancy, and childhood, the body needs zinc to grow and develop properly. Zinc also helps wounds heal and is important for proper senses of taste and smell.
How much zinc do I need?
The amount of zinc you need each day depends on your age. Average daily recommended amounts for different ages are listed below in milligrams (mg):
Birth to 6 months
2 mg
Infants 7–12 months
3 mg
Children 1–3 years
3 mg
Children 4–8 years
5 mg
Children 9–13 years
8 mg
Teens 14–18 years (boys)
11 mg
Teens 14–18 years (girls)
9 mg
Adults (men)
11 mg
Adults (women)
8 mg
Pregnant teens
12 mg
Pregnant women
11 mg
Breastfeeding teens
13 mg
Breastfeeding women
12 mg
What foods provide zinc?
Zinc is found in a wide variety of foods. You can get recommended amounts of zinc by eating a variety of foods including the following:
What kinds of zinc dietary supplements are available?
Zinc is present in almost all multivitamin/mineral dietary supplements. It is also available alone or combined with calcium, magnesium or other ingredients in dietary supplements. Dietary supplements can have several different forms of zinc including zinc gluconate, zinc sulfate and zinc acetate. It is not clear whether one form is better than the others.
Zinc is also found in some over-the-counter medicines such as cold lozenges and nasal sprays and nasal gels. Safety concerns have been raised about nasal sprays and gels that contain zinc. Some reports have described people who have permanently lost their sense of smell from using these products.
Am I getting enough zinc?
Most people in the United States get enough zinc from the foods they eat.
However, certain groups of people are more likely than others to have trouble getting enough zinc:
What happens if I don't get enough zinc?
Zinc deficiency is rare in North America. It causes slow growth in infants and children, delayed sexual development in adolescents and impotence in men. Zinc deficiency also causes hair loss, diarrhea, eye and skin sores and loss of appetite. Weight loss, problems with wound healing, decreased ability to taste food, and lower alertness levels can also occur.
Many of these symptoms can be signs of problems other than zinc deficiency. If you have these symptoms, your doctor can help determine whether you might have a zinc deficiency.
What are some effects of zinc on health?
Scientists are studying zinc to learn about its effects on the immune system (the body's defense system against bacteria, viruses, and other foreign invaders). Scientists are also researching possible connections between zinc and the health problems discussed below.
Immune system and wound healing
The body's immune system needs zinc to do its job. Older people and children in developing countries who have low levels of zinc might have a higher risk of getting pneumonia and other infections. Zinc also helps the skin stay healthy. Some people who have skin ulcers might benefit from zinc dietary supplements, but only if they have low levels of zinc.
Diarrhea
Children in developing countries often die from diarrhea. Studies show that zinc dietary supplements help reduce the symptoms and duration of diarrhea in these children, many of whom are zinc deficient or otherwisemalnourished. The World Health Organization and UNICEF recommend that children with diarrhea take zinc for 10–14 days (20 mg/day, or 10 mg/day for infants under 6 months). It is not clear whether zinc dietary supplements can help treat diarrhea in children who get enough zinc, such as most children in the United States.
The common cold
Some studies suggest that zinc lozenges or syrup (but not zinc dietary supplements in pill form) help speed recovery from the common cold and reduce its symptoms if taken within 24 hours of coming down with a cold. However, more study is needed to determine the best dose and form of zinc, as well as how long it should be taken before zinc can be recommended as a treatment for the common cold.
Age-related macular degeneration (AMD)
AMD is an eye disease that gradually causes vision loss. Research suggests that zinc might help keep early AMD from worsening into advanced AMD. In a large study, older people with AMD who took a daily dietary supplement with 80 mg zinc, 500 mg vitamin C, 400 IU vitamin E, 15 mg beta-carotene, and 2 mg copper for about 6 years had a lower chance of developing advanced AMD and less vision loss than those who did not take the dietary supplement. In the same study, people at high risk of the disease who took dietary supplements containing only zinc also had a lower risk of getting advanced AMD than those who did not take zinc dietary supplements. More research is needed before doctors can recommend zinc dietary supplements for patients with AMD. However, people who have or are developing the disease might want to talk with their doctor about taking dietary supplements.
Can zinc be harmful?
Yes, if you get too much. Signs of too much zinc include nausea, vomiting, loss of appetite, stomach cramps, diarrhea, and headaches. When people take too much zinc for a long time, they sometimes have problems such as low copper levels, lower immunity, and low levels of HDL cholesterol (the “good” cholesterol).
The safe upper limits for zinc are listed below. These levels do not apply to people who are taking zinc for medical reasons under the care of a doctor:
Birth to 6 months:
4 mg
Infants 7–12 months:
5 mg
Children 1–3 years:
7 mg
Children 4–8 years:
12 mg
Children 9–13 years:
23 mg
Teens 14–18 years:
34 mg
Adults:
40 mg
Are there any interactions with zinc that I should know about?
Yes. Zinc dietary supplements can interact or interfere with medicines that you take and, in some cases, medicines can lower zinc levels in the body. Here are several examples:
Tell your doctor, pharmacist, and other health care providers about any dietary supplements and medicines you take. They can tell you if those dietary supplements might interact or interfere with your prescription or over-the-counter medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients.
Where can I find out more about zinc?
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