Zinc is an important mineral involved in many bodily processes necessary for good health. Zinc is especially essential for immune function, protein synthesis, wound healing and cell growth and is required by the body to make many essential hormones.
Zinc deficiency is a worldwide problem, and is common even among otherwise well-nourished populations. The recommended daily allowance for zinc is 15 mg, but most Americans ingest approximately 10 mg daily from their diet. Medications such as protein pump inhibitors (PPIs) that reduce acid secretion interfere with absorption, and supplements in tablet form may not dissolve well in the stomach. Stress and infections can deplete zinc stores. Fitness enthusiasts are prone to zinc deficiency that results from sweating. Older patients with poor dietary habits are especially vulnerable to zinc deficiency. Alcohol, even in moderate amounts, can increase zinc excretion in the urine, resulting in low levels in the body.
Conditions associated with low zinc levels are intestinal malabsorption syndromes, cystic fibrosis, alcoholism, HIV infection, malignancy, uremia and chronic renal disease, and a weak immune system. Symptoms of deficiency include fatigue, poor appetite, digestive problems, and smell and taste dysfunction. Vision and hearing can be diminished by severe zinc deficiency. Some studies have associated zinc deficiency with depression. In deficient men, sexual function is affected and sterility is common.
Assessment of Zinc Deficiency – Methods of determining zinc levels include serum spectroscopy and analyses of white blood cells, hair or urine. However, the Zinc Taste Test is an easy, convenient method of assessing zinc deficiency in an office or other clinical setting. About two teaspoonfuls of 0.1% zinc sulfate heptahydrate solution is swished in the mouth and the patient is asked to describe the taste. No taste indicates a severe deficiency, while an immediately unpleasant taste indicates the person has adequate zinc levels. When compared with other methods, the Zinc Taste Test is inexpensive, easy to perform, and reasonably accurate; it can be repeated to follow progress; and its range indicates mild to severe states of zinc deficiency.
Treatment must be customized for each patient. If the zinc deficiency is severe, treatment should be initiated with the administration of a liquid preparation of zinc sulfate heptahydrate. In the elderly, 30 to 60 mg of zinc daily in divided doses may be needed. When requirements are great (for example, as a result of trauma, burns, etc.) up to 150 mg of zinc may be given daily for a short time, but the effect on the patient’s level of copper can lead to anemia.
Special attention must be paid to copper and selenium levels when supplementing zinc. Supplementation with these minerals should be done under the supervision of a knowledgeable, experienced health care professional.