Evidence shows that Vitamin C and Echinacea do not shorten colds. However, a new meta-analysis suggests that zinc lozenges do. By Day 5, 70% of people taking zinc had recovered from a cold compared to only 27% of people on placebo. The authors believe zinc roughly triples the rate of recovery.

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Evidence shows that Vitamin C and Echinacea do not shorten colds. However, a new meta-analysis suggests that zinc lozenges do. By Day 5, 70% of people taking zinc had recovered from a cold compared to only 27% of people on placebo. The authors believe zinc roughly triples the rate of recovery.