Zinc

Zinc is an essential trace mineral, so you get it through the foods you eat. Next to iron, zinc is the most common mineral in the body and is found in every cell. It has been used since ancient times to help heal wounds and plays an important role in the immune system, reproduction, growth, taste, vision, and smell, blood clotting, and proper insulin and thyroid function.

Zinc also has antioxidant properties, meaning it helps protect cells in the body from damage caused by free radicals. Free radicals may contribute to the aging process, as well as the development of a number of health problems, including heart disease and cancer. Antioxidants can neutralize free radicals and may reduce or even help prevent some of the damage they cause.

Your body doesn't need a large amount of zinc. The recommended daily allowance for adults is 8 - 11 mg. It’s common to have slightly low levels of zinc, but taking a multivitamin, plus eating a healthy diet, should give you all the zinc you need.

It's rare for people in industrialized countries to be seriously deficient in zinc. Low zinc levels are sometimes seen in the elderly, alcoholics, people with anorexia, and people on very restricted diets. People who have malabsorption syndromes, such as Crohn's disease or celiac disease, may also be deficient in zinc.

Symptoms of zinc deficiency include loss of appetite; poor growth; weight loss; lack of taste or smell; poor wound healing; skin problems such as acne, atopic dermatitis and psoriasis; hair loss; lack of menstrual period; night blindness; white spots on the fingernails; and depression.

Zinc reduces the amount of copper your body absorbs, and high doses of zinc can cause a copper deficiency. For that reason, many doctors recommend that you take 2 mg of copper along with a zinc supplement.

Acne

Some studies suggest that taking oral zinc supplements may help improve acne. However, most studies used a high dose of zinc that could have toxic effects, and not all studies found any benefit. There is some evidence that a topical form of zinc, used along with the topical antibiotic erythromycin, might be helpful.

Age-Related Macular Degeneration(AMD)

Doctors often recommend zinc to slow the progress of AMD, an eye disease that occurs when the part of the retina that is responsible for central vision starts to deteriorate. A major clinical trial, the Age Related Eye Disease Study (AREDS1), found that people who had macular degeneration could slow down the damage by taking zinc (80 mg), vitamin C (500 mg), vitamin E (400 mg), beta-carotene (15 mg), and copper (2 mg). If you have macular degeneration, ask your doctor whether these vitamins and minerals might help you. This is a very large amount of zinc and should only be used under a doctor's supervision.

A new study, AREDS2, is examining exactly what role zinc plays in macular degeneration.

Colds

Many people believe that taking zinc lozenges or using zinc nasal spray when they first show signs of a cold can reduce the duration and severity of symptoms. Not all studies agree, but most suggest that zinc acetate or gluconate lozenges may help you get over a cold faster. In one study, people who had early symptoms of a cold took either a lozenge with 13.3 mg of zinc gluconate or placebo. Those who took the zinc saw symptoms, such as coughing, runny nose, and sore throat, disappear faster than those who took placebo. But researchers aren’t sure what type of zinc works best for colds and whether flavorings added to the lozenges might affect how they work.

Zinc nasal sprays are controversial. Some studies have found zinc nasal sprays may help reduce cold symptoms, but other studies have found no effect. In addition, zinc nasal sprays may cause some people to lose their sense of smell. To be safe, talk to your doctor before using a zinc nasal spray.

There is some evidence that zinc supplements (not lozenges) may help lower the risk of getting a cold in the first place. In one study, elderly people in a nursing home who had normal levels of zinc had a lower risk of pneumonia, fewer new antibiotic prescriptions and fewer days of antibiotic use. More and better studies are needed that examine which kinds of zinc may be effective and against which kinds of cold viruses.

Sickle Cell Disease

People who have sickle cell disease are often deficient in zinc. Studies suggest that taking zinc supplements may help reduce symptoms of the disease. Children who took zinc showed improvements in height and weight, and had fewer sickle-cell crises.

Stomach Ulcers

Some studies suggest that zinc may help speed the healing of stomach ulcers. The studies used a form of zinc not available in the U.S.

Attention Deficit Hyperactivity Disorder (ADHD)

For children who have low levels of zinc, some evidence suggests that taking zinc may cause a slight improvement in symptoms, reducing hyperactivity, impulsivity, and impaired socialization in children. However, there was no change in attention deficit symptoms. Zinc may be most helpful to children with a high body mass index, low levels of free fatty acids in their blood, and low levels of zinc.

Herpes simplex (Cold Sores)

Cold sores are caused by the herpes simplex virus. In one study, people with cold sores used either a zinc oxide cream or placebo every 2 hours until their cold sores got better. Those who used the zinc cream had fewer symptoms and got better faster.

HIV/AIDS

It’s common for people with HIV or AIDS to have low levels of zinc, even before symptoms appear. In people with AIDS, low levels of zinc may be a result of poor absorption, medications, and loss of this important nutrient through vomiting or diarrhea. Low levels of zinc can make the body more susceptible to infection, called an opportunistic infection. Some studies show that HIV positive people who take zinc have fewer infections, gain more weight, and have a better immune system response. But not all studies agree, and one even suggests that taking zinc may be associated with higher death rates. If you have HIV or AIDS, talk to your doctor before taking zinc or any supplement.

Wilson's Disease

Preliminary evidence suggests that zinc may help treat Wilson's disease, a condition which causes copper to build up in the body. Because zinc reduces how much copper the body absorbs, it may help reduce levels of copper in people with Wilson's disease.

Other

Other conditions may increase the need for zinc or affect how your body absorbs or uses this mineral. Researchers don’t know, however, whether taking zinc will help treat any of these conditions:

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Review Date: 7/16/2013  

Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

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