Zinc is an essential nutrient, which is available in foods. Supplementation may be needed, however, if you do not get enough in your diet or are not able to absorb or retain enough zinc. Increasingly, zinc supplements are being recommended for a variety of health conditions, but large doses of zinc can be toxic, so it is important to discuss zinc and health-related concerns with your doctor.
Uses of Zinc
Zinc supplements are often added to the diet to treat zinc deficiencies, and the use of larger doses of zinc is becoming more common. Conditions that respond favorably to additional zinc include anorexia, chronic diarrhea, alcoholism, diabetes, GI surgery, Crohn's disease, tinnitus, HIV, recurring infections, severe burns, Wilson's disease, and sickle cell anemia. Zinc supplementation is recommended to help strengthen the male reproductive system. It is also routinely used by athletes to counteract zinc loss due to perspiration.
Recommended Daily Dosage
The U.S. Recommended Dietary Allowance, or RDA, is the minimum amount of a nutrient needed by most people to stay healthy. The RDA for zinc is 8 mg daily for women and 11 mg daily for men. The U. S. Food and Nutrition Board has established the upper limits, or UL, of safe daily intake for most nutrients. The UL for zinc is 40 mg per day. Zinc consumption exceeding that amount can be too much of a good thing, increasing the risk of adverse effects.
Warning
Because too much zinc can cause serious health problems, dosages should take into consideration the daily amount of zinc already generated from diet. When the zinc that is consumed each day is within normal limits, side effects are minimal. However, if too much zinc is taken at once or large doses are taken daily over an extended period of time, symptoms such as headaches, nausea, vomiting, stomach cramps, diarrhea and loss of appetite may develop.
Zinc Toxicity
Large dosages of zinc can interfere with the absorption of essential minerals, particularly, magnesium and copper. A zinc-induced copper deficiency can inhibit the transport of iron in the body and result in anemia. Toxicity from excessive zinc ingestion can reduce immune functioning and reduce levels of the beneficial HDL cholesterol. It may also contribute to the development of cardiac and urinary tract problems, as well as increase a man's risk of developing prostate cancer.
Recovery from Toxicity
Zinc is relatively non-toxic when taken at recommended dosage levels. If symptoms of toxicity arise, most people can recover -- even after taking large amounts of zinc daily for many months. Serum zinc levels will usually return to normal once zinc supplementation is reduced or discontinued, and compromised vitamin and mineral levels are supplemented. Suspected problems should be assessed and treated by a doctor.
Member Comments