True. Zinc won’t prevent a cold, but it can shorten its duration. Zinc from food (beef, dark poultry meat, shellfish) probably won’t help, as you can’t get enough—but zinc lozenges might. In a study in the Journal of Infectious Diseases, adults who took zinc in lozenge form (13.3 mg every 2 to 3 hours for as long as their cold lasted) within a day of noticing the telltale signs kicked the bug about 3 days sooner than those who got a placebo. Though that dose exceeds the recommended daily max of 40 mg, it’s safe for a 3- to 5-day time period, says study author Ananda Prasad, M.D., Ph.D. Scientists think zinc binds to cell receptors in the mouth and throat, blocking the cold virus from attaching and spreading. Zinc comes in many forms, but only lozenges have been shown to be effective. Skip nasal sprays and swabs: they may damage your sense of smell.