Zinc is an essential mineral often touted as a natural remedy for colds. While available in supplement form, lozenges, and nasal sprays, zinc is also naturally present in foods like oysters, red meat, poultry, beans, nuts, and whole grains. Scientists theorize that zinc may fight colds by stopping the cold virus from attaching to the nasal lining, as well as by suppressing inflammation.
The Science Behind Zinc and Colds
To date, research on the use of zinc in treatment and prevention of colds has yielded mixed results. For instance, a 2003 research review found that zinc may help reduce the duration and severity of colds when taken within 24 hours of first experiencing cold symptoms. However, in a more recent report (published in 2007), investigators found conflicting evidence of zinc's cold-fighting effects: Of the 14 studies reviewed, seven showed that zinc had a beneficial effect, while the other seven showed no effect.
Other research indicates that different forms of zinc may produce different effects. In a 2000 study of 273 people with colds, scientists discovered that zinc gluconate lozenges significantly reduced the duration of illness but failed to lessen how severe the symptoms were. Treatment with zinc acetate lozenges, on the other hand, affected neither cold duration nor severity.
Is Zinc Safe?
Some research suggests that using zinc nasal sprays may dull your sense of smell. In a 2010 study, scientists determined that chemicals in zinc nasal sprays led to the loss of sense of smell among 25 patients recruited from a nasal dysfunction clinic.
Zinc supplements may also interact with several types of medications, including certain antibiotics and diuretics.
Should You Use Zinc to Fight Colds?
So far, the data on zinc's effectiveness in fighting colds are inconclusive, according to the National Institutes of Health. Therefore, zinc products cannot currently be recommended for treatment or prevention of colds. While zinc products may offer some advantage when managing the common cold, it's important to practice other cold-fighting strategies (such as washing your hands regularly and strengthening your immune system by following a healthy diet, exercising regularly, managing your stress, and getting sufficient sleep).
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