How can zinc be harmful

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.

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.

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. 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 otherwise malnourished.

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. 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. AMD is an eye disease that gradually causes vision loss.

Research suggests that zinc might help slow AMD progression. In a large study among older people with AMD who were at high risk of developing advanced AMD, those who took a daily dietary supplement with 80 mg zinc, mg vitamin C, 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. People who have or are developing the disease might want to talk with their doctor about taking dietary supplements.

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 daily upper limits for zinc include intakes from all sources—food, beverages, and supplements—and are listed below.

These levels do not apply to people who are taking zinc for medical reasons under the care of a doctor:. 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 healthcare 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. That all depends on your age and your dietary intake. Having said that, zinc deficiency is rare in the United States. Symptoms of zinc deficiency include hair loss, diarrhea, eye and skin sores and loss of appetite.

But keep in mind that these symptoms can be signs of other problems as well, so it is important not to self-diagnose. Your doctor can determine this with a simple blood test. Also, the way in which zinc is administered matters. Zinc-containing syrup and lozenges are most effective at fighting colds because they allow the zinc to make contact with the rhinovirus in those areas.

Adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches. Intakes of — mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function and reduced immune function.

Zinc can also interact with certain medications such as antibiotics, diuretics, and penicillamine a drug used to treat rheumatoid arthritis. Supplements are not regulated by the FDA so you may be at risk of consuming other harmful ingredients such as lead or other contaminants, and the amount listed on the label might not be reflective of how much is in it; it could be much more or much less. Additionally, vitamins and minerals work synergistically with one another when obtained from their natural food sources.

The Tolerable Upper Intake Level Us is defined as the highest level of daily intake that is likely to pose no adverse health effects in most human individuals. If we combine this information with your PHI, we will treat all of that information as PHI, and will only use or disclose that information as set forth in our notice of privacy practices.

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