Zinc is used commonly to enhance wound healing. Taken before and after surgery, zinc has been shown in numerous studies to speed recovery time and reduce the incidence of postoperative complications, such as wound infections. This use has the potential to greatly cut down on hospital costs. In some studies, the hospital stay has been reduced by more than half. Zinc may be helpful in speeding healing after burns or injury as well. This wound-healing effect is a likely result of zinc's function in DNA synthesis. The results seem to be particularly pronounced when there is zinc deficiency prior to the treatment. In many of the wound-healing studies, zinc dosages of 150 mg. per day were used. It is possible that lower amounts, even 30-60 mg. per day, would produce these effects.

Zinc may be useful in treating such skin problems as boils, bedsores, general dermatitis, and acne. Research on zinc and acne shows variable results, but many teenagers and others have been helped, especially when zinc deficiency was present; it is likely that other factors and nutrients are also involved in acne. Leg ulcers have healed more rapidly with zinc treatment in a dose of 150 mg. per day. Internally, gastric ulcers have responded favorably to zinc in a similar dosage. Psoriasis is even occasionally responsive to zinc supplementation. White spots on the fingernails, which can be a result of zinc deficiency, may respond also to zinc treatment. Zinc may also be helpful to general nail health, as well as skin and hair health. Cataracts also seem to be associated with zinc deficiency and have been helped by treatment.

My friendly travel agent developed a case of hoarseness that persisted for more than a month. Her otolaryngologist diagnosed chronic inflammation and had suggested long-term quietude and learning to live with it—neither of which was a big hit. In passing (I was quite aware of the foibles of her diet), I suggested zinc lozenges. She began sucking on 3–4 daily and within a week her voice was back. In this case, the $5 bottle of zinc helped more than the $70 office visit. I believe that she was zinc deficient, and that the zinc supplement helped to heal her inflamed tissue.

Zinc is used in a variety of immune problems. It is one of the supportive nutrients used to treat lowered immunity. Zinc has been shown to increase T lymphocyte production and enhance other white blood cell functions. Recent double-blind studies verify that zinc therapy is helpful in reducing the incidence and severity of colds and other infections. Also, infections such as herpes, trichomoniasis, or AIDS may be curtailed some with zinc, especially if it is deficient. Sucking a 25-50 mg. dissolvable zinc lozenge can provide dramatic relief in some cases of sore throat and has been shown to prevent the progression of viral flu symptoms. Individuals with allergies and environmental sensitivities may benefit from zinc supplementation. Measuring zinc status and following it during treatment may be useful in validating its positive effects.

For male prostate problems, there is no scientific evidence that zinc works, though there are a great many anecdotal accounts from men who claim to have been helped by zinc. Mild or persistent nonbacterial infections or congestion have commonly been helped by oral zinc treatments. Of course, when zinc deficiency produces such sexual symptoms as infertility, impotency, or poor sexual development, supplementation of this mineral may have great benefit. There is some suggestion that the prostate enlargement that comes with age, termed benign prostatic hypertrophy (BPH), is related to low zinc (and cadmium toxicity), and that regular zinc supplementation may prevent this common problem. More research is needed to clearly evaluate zinc's relationship to prostate and sexual health.

Zinc may also be beneficial in rheumatoid arthritis, for which it has been shown to reduce symptoms; in preventing dental caries by strengthening tooth enamel; and with symptoms of heart disease, where the zinc-copper ratio may be important. The use of zinc in cancer prevention and the support of patients with cancers such as Hodgkin's disease and leukemia has been the subject of some interest.

Zinc therapy can reduce cadmium toxicity from pollution or from cadmium in water or foods. Cadmium toxicity may aggravate hypertension, atherosclerosis, and heart disease and produce complications of hypertension or stroke.

Zinc with vitamin B6 has also been used in the nutritional treatment of schizophrenia and, given along with manganese, has been helpful in some cases of senility. Zinc treatment may help with the loss of taste sensation that comes especially with aging, which is often due to zinc deficiency, and it may help stimulate the taste for food in patients with anorexia nervosa. Menstrual irregularity and female sexual organ difficulties may have some relationship to zinc levels and be helped by zinc therapy, though copper may be more important for these areas in women.

Deficiency and toxicity: Zinc is fairly nontoxic, especially in amounts of less than 100-150 mg. of elemental zinc daily, though this much zinc is probably not really needed and may interfere with the assimilation of other minerals. Zinc salts such as gluconate or sulfate are commonly available in 220 mg. tablets or capsules, each providing 55 mg. of elemental zinc. Taking one of these two or three times daily may cause some gastrointestinal irritation, nausea, or diarrhea but is more likely to have positive effects. Excessive supplementation may cause some immune suppression, premature heartbeats, dizziness, drowsiness, increased sweating, muscular incoordination, alcohol intolerance, hallucinations, and anemia, some of which is due to copper deficiency. More than 2 grams of zinc taken in one dose will usually produce vomiting. If not, it will likely lead to other symptoms until the body clears the excess zinc. Luckily, only a certain amount of it will be absorbed.

Zinc may interfere with copper absorption, so taking regular zinc supplements without copper can cause copper deficiency. This will interfere with iron metabolism and possibly cause anemia, as copper and iron are important in red blood cell formation. We usually need supplemental copper and vitamin A to balance the effect of extra zinc. Some formulas, for example, Nutrilite's product, A plus Zinc, contain vitamin A and zinc together, which improves the effect of both; additional copper, about 2 mg., might also be supplemented daily, though at another time than the zinc.

• Diet—low in zinc or high in copper; high in fiber, phytates, clay, alcohol, or phosphates, all of which bind zinc in the intestines and reduce absorption; food grown in low-zinc soils.
  
• Aging—when zinc absorption and intake are often reduced.
  
• Pregnancy—when zinc needs are increased.
  
• Growth periods—infancy, especially with increased copper intake levels and for those on low-zinc formulas; puberty, especially in adolescent boys.
• Birth control pills—use of these increases copper levels and thus reduces zinc.
• Premenstrual symptoms—associated with low zinc.
• Increased copper intake—high copper intake in water, food, or supplements will reduce zinc.
• Fasting or starvation—causes zinc depletion and increases needs for zinc.
• Serious illness or injury—causes zinc depletion and increases needs due to tissue healing.
• Hospitalization—stress of illness or treatment, particularly intravenous therapy without zinc supplementation.
• Stress—increases zinc use and needs.
• Burns—increases needs for tissue healing and dealing with stress.
• Acute or chronic infections—greater requirements from stress and for healing.
• Surgery—increased requirements for dealing with stress and for healing.
• Alcoholism—often associated with low zinc intake and higher needs; alcohol flushes zinc from the liver, causing increased losses.
• Diuretic therapy—may cause extra zinc losses.
• Psoriasis—rapid skin activity may deplete zinc.
• Parasites—cause zinc depletion and poor absorption.
• Malabsorption—from pancreatic insufficiency or after gastrointestinal surgery.
• Cirrhosis—zinc levels may be half of normal.
• Renal disease—causes increased zinc
• Chronic disease—metabolic and debilitating disease such as cancer.
• Athletics—increased zinc losses in sweat.
• Cadmium toxicity—interferes with zinc absorption and utilization.

Other problems associated with low zinc levels are peptic ulcers, pernicious anemia, cystic fibrosis, and mongolism.

Zinc deficiency is very likely more common and more complex than previously thought. It was first identified in Iran and Egypt in 1961, in male dwarfs with slow growth and poor sexual development. The unleavened bread that is a staple in the diet there is high in the phytates that bind zinc, and a type of clay used for cooking in Iran also ties up zinc. Zinc treatment was found to help these conditions, stimulating growth and sexual development.

Aging is one of the main factors in zinc deficiency. However, some recent environmental changes have also contributed to the deficiency problem. Soil losses and losses due to food processing are two of the main factors in zinc depletion in foods. With the change from iron- and zinc-containing water pipes to copper ones, not only is zinc intake decreased, but the additional copper interferes further with zinc absorption. The average diet, especially one with low protein intake, supplies only 8-11 mg. daily (the RDA for adults is 15 mg.).

In general, both infants and adolescents have more zinc deficiency, as do the elderly and women, often due to low intake. With the average American diet, we need to eat about 3,400 calories to obtain our 15 mg. of zinc, and most people do not eat that much. Good-quality food is needed, and therefore poor people are more likely to experience zinc shortages.

The subject of our diet and zinc deficiency is an important one. The all-too-typical advanced technology, antinature diet that is high in refined grains, fat, sugar, convenience foods, and fried meats, is often low in zinc and many other important trace minerals and B vitamins. Also, strict vegetarians and consumers of much grain and little animal protein may not obtain sufficient zinc.