Zinc

Zinc is a trace mineral; it is essential and critical, yet needed in only small amounts to function optimally. The recommended dose is 12 milligrams and you should not get more than 30 grams/day through your diet and supplementation.

Zinc functions, as a co-factor for numerous enzymes essential for growth and development and protection from free radical attacks. Immune system function and the wound healing process are dependent on zinc. . Recent research indicates that a higher level of zinc in the tissues corresponds with a lower risk of esophageal cancer. People who smoke, incur scarring or injury to the esophagus or have long-term acid reflux disease are at risk for esophageal cancer.

Most Americans get adequate amounts of zinc in their diets. The best food sources are oysters, red meats, lamb, poultry, fish and dairy products. Vegetarians, pregnant women and the elderly might be at risk of deficiency. Although whole grains and legumes are good sources of zinc they contain substances that can block zinc absorption. Nuts, tahini paste, yeast and dairy products are reliable dietary sources. Zinc from plant sources is more likely to be absorbed when eaten with animal foods.

There is always too much of a good thing. Overdosing on zinc can impair iron and copper absorption, reduce immune function, and lower the “good” cholesterol levels in your blood.

If you think you are at risk for deficiency discuss supplementation with your health care provider.

Donna Tinnerello, MS, RD, CDN

May 2005