Zinc Usage

Zinc is an important element that is found in every cell in the body. More than 300 enzymes in the body need zinc in order to function properly. The effect of zinc on acne is not clear, though studies...

Read more about Acne and Zinc.

When you take zinc as a lozenge or nasal gel or spray, you are not using it as a nutrient. Instead, certain forms of zinc release ions that are thought to directly inhibit viruses in the nose and...

Read more about Viral Upper Respiratory Infections (Colds and Influenza) and Zinc Lozenges and Nasal Sprays and Gels.

Use of zinc nasal spray or zinc lozenges at the beginning of a cold may reduce the duration and severity of symptoms, but study results are somewhat inconsistent. ¹ These treatments are thought to work by directly interfering with viruses in the nose and throat, and involve relatively high doses of zinc used for a short time.

Zinc can also be taken long-term at nutritional doses orally to improve overall immunity and reduce risk of infection; ² however, this approach probably only works if you are deficient in zinc to begin with.

A significant body of evidence suggests that oral zinc can reduce symptoms of acne . ³ But, in most studies, potentially toxic doses were used, and in any case, the benefits appear to be rather slight.

Growing evidence suggests that oral zinc, especially in combination with antioxidants, can help slow the progression of macular degeneration . ⁴ Oral zinc has also shown promise for sickle cell anemia , ⁵ ADHD , ⁶ and stomach ulcers . ⁷ Zinc has also been shown to be beneficial for acute diarrhea in children, the most convincing evidence coming from studies done in developing countries. ⁸ This suggests that zinc is most useful for this condition in the presence of a nutritional deficiency.

Topical zinc may be helpful for cold sores . ⁹ Zinc has shown some promise for treating dysgeusia (impaired taste sensation). In a study of 50 people with idiopathic dysgeusia (impaired taste sensation of no known cause), use of zinc at a rather high dose of 140 mg daily improved taste ability. ¹⁰ Another study enrolled seniors with dysgeusia and gave them either placebo or 30 mg of zinc daily; the results were equivocal. ¹¹ Dysgeusia can also be caused by radiation therapy in the vicinity of the mouth, but the overall evidence regarding the use of zinc for this purpose is more negative than positive. ¹² Kidney dialysis also impairs taste sensation, but once more zinc supplements failed to prove effective. ¹³ ( Note: Use of any mineral supplement by people undergoing kidney dialysis is potentially dangerous.)

In one study, use of zinc appeared to modestly decrease inflammation of the mucous membranes and skin caused by radiation therapy. ¹⁴ Weak and/or contradictory results have been seen in studies of zinc for anorexia nervosa , ¹⁵ depression , ¹⁶ rheumatoid arthritis , ¹⁷ enhancing sexual function in men on kidney dialysis, ¹⁸ tinnitus , ¹⁹ and warts . ²⁰ Some, but not all, studies have found that HIV-positive people tend to be deficient in zinc, with levels dropping lower in more severe disease. ^{21 22 23 24 25} Higher zinc levels have been linked to better immune function and higher CD4+ cell counts, whereas zinc deficiency has been linked to increased risk of dying from HIV. ^{26 27} One preliminary study among people taking AZT found that 30 days of zinc supplementation led to decreased rates of opportunistic infection over the following 2 years. ²⁸ However, other research has linked higher zinc intake to more rapid development of AIDS. ²⁹ Another failed to find that zinc supplementation reduces diarrhea associated with HIV. ³⁰ The bottom line: If you have HIV, consult your physician before supplementing with zinc.

Although the evidence that zinc works is not yet meaningful, the supplement is sometimes recommended for the following conditions as well: Alzheimer's disease , ^{31 32 33} and minor memory loss in seniors, ³⁴ benign prostatic hyperplasia , ^{35 36 37 38 39 40} bladder infection , cataracts , diabetes , ^{41 42} Down's syndrome, ^{43 44} infertility in men , ⁴⁵ inflammatory bowel disease ( ulcerative colitis and Crohn's disease ), ^{46 47 48} osteoporosis , ⁴⁹ periodontal disease , prostatitis , ⁵⁰ psoriasis , and wound and burn healing. ^{51 52} An 8-week, double-blind trial of zinc at 67 mg daily failed to find any benefit for eczema symptoms. ⁵³