If you want to avoid a cold, or get rid of one:
The herb thyme is your friend. It contains an oil called thymol that kills germs on contact and is an active ingredient in cold medications, like Vicks VapoRub. It can stop an infection short by activating white blood cells and boosting immunity. And if you’re already sick, thyme can reduce congestion, coughs and nasal irritation. So cook with thyme, or make tea. Add 2 teaspoons of fresh thyme to hot water, steep for 10 minutes, strain and sip. And for a stuffy nose, add thyme to boiling water, cover your head with a towel, lean over and inhale the steam.