Zinc stops cold viruses from sticking to your nose cells and making copies of themselves, which helps fight off the cold and reduce swelling.

Zinc lozenges might help with cold symptoms, but lab tests show zinc doesn't really fight cold viruses directly, so there's probably another reason they work.

Zinc lozenges don't help reduce how long colds last or how bad they feel, whether you catch a cold naturally or in a study where they give you a cold virus.

Zinc can stop cold viruses from copying themselves and spreading in lab tests.