Zinc deficiency
Zinc deficiency can occur when zinc intake is inadequate, when there are increased losses of zinc from the body, or when the body's requirement for zinc increases. There is no specific deficiency disease associated with zinc. General signs of zinc deficiency include poor appetite, weight loss, delayed healing of wounds, taste abnormalities, and mental lethargy. As body stores of zinc decline, these symptoms worsen and are accompanied by diarrhea, hair loss, recurrent infection, and a form of dermatitis -- a skin disorder. Zinc deficiency has also been linked to poor growth in childhood.
Is there a risk of taking is too much zinc?
The health risk of taking too much zinc is moderate to high. Zinc toxicity has been seen in both acute and chronic forms. Intakes of 150 to 450 mg of zinc per day have been associated with low copper status, altered iron function, reduced immune function, and reduced levels of high-density lipoproteins (the good cholesterol). One case report cited severe nausea and vomiting within 30 minutes after the person ingested four grams of zinc gluconate (570 mg elemental zinc). The 1989 RDA committee stated that "chronic ingestion of zinc supplements exceeding 15 mg/day is not recommended without adequate medical supervision." The National Academy of Sciences is currently reviewing recent research and considering new recommendations on zinc intake and risk.
How much do we need?
The Recommended Dietary Allowance (RDA) is the average daily dietary intake level that is sufficient to meet the nutrient requirements of nearly all (97 - 98%) individuals in a given life-stage and gender group. The 1989 RDAs for zinc in milligrams (mg), are: 15 mg for adult men and 12 mg for adult women; 15 mg during pregnancy; 19 mg for the first six months of breast feeding and 16 mg during the second six months of nursing a baby.
Quote from Healthlink.
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Jade