While getting a cold may not be your main concern during summer, there’s still a risk. There’s good news; Zinc acetate lozenges may reduce the duration of the common cold by nearly 3 days, especially when taken within 24 hours of the first signs and symptoms of a cold, according to a recent analysis.
Most colds are caused by a type of virus called rhinovirus, which thrives and multiplies in the nasal passages and throat (upper respiratory system). Zinc may work by preventing the rhinovirus from multiplying. It may also stop the rhinovirus from lodging in the mucous membranes of the throat and nose.
Among 199 patients with the common cold who participated in three randomized placebo-controlled trials, the effect of zinc lozenges was not modified by allergy status, smoking, symptom severity, age, sex, or ethnic group.
One study indicated that zinc lozenges might be more effective for common cold patients with allergies, but we showed that the efficacy is the same for those with and without allergies. Common cold patients should be encouraged to try zinc acetate lozenges not exceeding 100 mg of elemental zinc per day for treating their colds, said Dr. Harri Hemila, lead author of the British Journal of Clinical Pharmacology analysis.
Zinc has also been associated with faster resolution of nasal congestion, nasal drainage, and sore throat, as well as improvement of cough. But be careful. More than 150mg/day of zinc may lead to zinc toxicity, with side effects including reduced immune function, according to the NIH. That could leave you worse off than when you started.
Certain side effects and toxicities, including loss of sense of smell, have been associated with some zinc preparations used to treat colds. In fact, the U.S. FDA has issued a public health advisory warning that three zinc-containing products for topical (intranasal) use should not be used due to the risk of developing this side effect.
The NIH notes that children and the elderly with zinc deficiency in the developing world have been shown to be more vulnerable to pneumonia and other infections. The agency reports zinc allows the body to produce and activate T-cells (t-lymphocytes), which are some of the white blood cells that respond to infections.
If you want to use zinc to prevent colds, the safest course is to talk to your doctor before considering using the product.