Zinc works, if only somewhat, to cure the common cold.
A review of the available scientific evidence suggests taking zinc within a day of the onset of cold symptoms speeds recovery. It may also help ward off colds, say the authors of the Cochrane Systematic Review that included data from 15 trials involving 1,360 people.
The trials illustrated the ability for the cold to be remedied and even reversed by taking zinc. However, zinc can only be a temporary solution, given the fact that long term exposure is toxic. Doctors are also not confident in its effects, because they are unsure about the optimum dosage (For instance, Zicam, which contains zinc, destroyed some user's sense of smell). So, take some zinc if you're getting sick, but don't get too excited: We haven't triumphed over the cold yet.