Is zinc beneficial or detrimental for respiratory diseases?
Excessive inhalation of zinc salts, such as zinc oxide, has previously been implicated in causing metal fume fever, an influenza-like illness that results from an acute or subacute respiratory tract inflammation (mild interstitial pneumonia) and is characterized by bronchial hyper-responsiveness, myalgias and fever. If left untreated or undetected fume fever can also lead to occupational asthma.50 In contrast brief exposures to zinc sulphate aerosols have been shown to protect against allergic bronchoconstriction in guinea pigs, possibly by blocking histamine release from mast cells.51 Zinc has also been shown to directly decrease the incidence of respiratory infections in young children from developing countries. It has been reported that there was a 45% decrease in the incidence and prevalence of acute lower respiratory infection in children of 6–35 months of age receiving 10 mg of supplemental Zn daily.52 Similarly, Zn may be beneficial in reducing the severity of symptoms of the co
