We all need zinc to help protect against oxidative stress and complete DNA repair, but deficiencies in this trace mineral may be common and increase risks of cancer, DNA damage, infectious diseases and suboptimal immune function. The older you get, the greater the risk of running low on zinc. An estimated 12 percent of the U.S. population is probably at risk of zinc deficiency, and up to 40 percent of seniors may be deficient because absorption of zinc slows with age and because dietary intake may not meet your nutritional needs, according to experts at the Linus Pauling Institute at Oregon State University. One recent study found that even a minor zinc deficiency can result in increased DNA damage. Zinc deficiencies have been linked to prostate cancer and to esophageal, breast and head and neck cancers and may contribute to infections and to autoimmune diseases. Unfortunately, tests for zinc status aren't very good. The best dietary sources are beef and poultry; zinc is poorly absorbed from plants. The recommended daily allowance is 8 mg for women and 11 mg for men, but I generally recommend taking 15 mg of zinc daily - or up to 30 mg daily if you don't eat many foods of animal origin.
The best plant sources of zinc are legumes (dried beans, garbanzos, black-eyed peas, lentils, peas, and whole soy products), pumpkin seeds, whole grains and nuts.