Facts about Zinc¹

Linda B. Bobroff²

Why do we need zinc?

Zinc is a mineral that is found in almost every cell in our bodies. It’s needed for hundreds of chemical reactions. Zinc helps with:

Keeping our immune system healthy
Use of vitamin A in the body
Normal cell replacement

Zinc is needed for optimal growth and development. It is critical for pregnant women and children to get enough zinc in their diets.

What happens if we don’t get enough zinc?

Zinc deficiency can affect the immune system, cognitive function, and growth in children. Severe zinc deficiency also can cause diarrhea, hair loss, poor appetite, skin disorders, and changes in taste. People who drink alcohol in excess are at high risk for zinc deficiency (and other health problems).

How much zinc do we need?

The recommended daily intakes of zinc for most adults are as follows:

Table 1.

Life Stage

Amount (mg/day)

Men, ages 19+

Women, ages 19+

Pregnancy*

Breastfeeding**

*Pregnant teens need 12 mg

** Breastfeeding teens need 13 mg

mg = milligrams of zinc

How can we get enough zinc?

The best food sources of zinc are seafood, meat, poultry, beans, nuts, and some fortified cereals. The zinc found in animal foods is easily absorbed by the body. Whole grains also contain zinc, but it is not well absorbed.

Here are some foods and the amount of zinc they contain:

Table 2.

FOOD	ZINC (mg/serving)
Oysters, cooked, 3 oz	75
Crab meat, cooked, 3 oz	7
Beef chuck, lean, cooked, 3 oz	7
Fortified cereals, 1 cup	3–4
Chicken leg, cooked, 3 oz	3
Hamburger (fast food), small	2.6
Baked beans, canned, ½ cup	2
Pecans, chopped, ¼ cup	1.2
Milk, 1 cup	1
mg = milligrams oz = ounces

What about supplements?

Multivitamin supplements with minerals usually contain zinc. These supplements can be used by people who may not get enough zinc in their diets. People 51 years of age and older, pregnant women, and nursing moms may benefit from taking a supplement containing zinc.

Many people believe that taking zinc lozenges decreases the duration of colds. However, most studies have not found that zinc lozenges are helpful. This is an area that needs more research.

How much is too much?

High intakes of zinc can be toxic. Large amounts of zinc also can interfere with absorption of other minerals. You should not get more than 40 mg of zinc a day, from food and supplements together.

Where can I get more information?

The Family and Consumer Sciences (FCS) agent at your local Extension office may have written information and nutrition classes for you to attend. Also, your doctor or a registered dietitian (RD) can provide you with reliable information.

Reliable nutrition information may be found on the Internet at the following sites:

http://solutionsforyourlife.ufl.edu

http://www.nutrition.gov

http://www.ars.usda.gov

http://ods.od.nih.gov/factsheets/Zinc_pf.asp

Footnotes

This document is FCS8705, one of a series of the Department of Family, Youth and Community Sciences, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. First published: June 2001. Revised: January 2006; June 2009.

Linda B. Bobroff, PhD, RD, LD/N, professor; Department of Family, Youth and Community Sciences; Cooperative Extension Service; Institute of Food and Agricultural Sciences; University of Florida; Gainesville, FL 32611.

The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.

U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Millie Ferrer-Chancy, Interim Dean.

Facts about Zinc1