Why Zinc Is One of the Most Popular Immune Supplements
Zinc
Zinc is an essential trace mineral available as a dietary supplement and is required for hundreds of biological processes throughout the body. It is best known for its roles in immune function, wound healing, growth and development, and the maintenance of normal taste and smell. Because the body does not store large amounts of zinc, regular intake from food or supplements is necessary.
What It Does
Zinc is found in cells throughout the body and supports DNA synthesis, protein production, cell division, and normal immune-system activity. It also contributes to growth during childhood and pregnancy, tissue repair, and healthy sensory function.
Health Uses
Zinc supplements are primarily used to prevent or treat zinc deficiency. People with low zinc levels may experience impaired immunity, delayed wound healing, hair loss, reduced appetite, or changes in taste and smell. Research also shows that adequate zinc is important for maintaining normal immune-cell function, although supplementation is most beneficial when a deficiency exists.
Common Forms
Several supplemental forms are available, including zinc gluconate, zinc acetate, zinc sulfate, zinc citrate, and zinc picolinate. These forms differ somewhat in absorption and tolerability, but all are intended to provide elemental zinc. Zinc is often included in multivitamins as well as stand-alone supplements and lozenges.
Safety and Dosage
The recommended dietary allowance (RDA) for adults is generally 8 mg/day for women and 11 mg/day for men. For most adults, the tolerable upper intake level from food and supplements combined is 40 mg/day. Excessive long-term supplementation can cause nausea, stomach upset, and copper deficiency, which may lead to anemia or neurological problems. Zinc can also interact with some medications, including certain antibiotics.
Dietary Sources
Many foods naturally contain zinc. Rich sources include oysters, red meat, poultry, seafood, dairy products, beans, nuts, seeds, and whole grains. Obtaining zinc from food is generally preferred when dietary intake is adequate.