evidence: Putting onions in your socks might sound odd, but onions have a long history as a medical remedy, and some people say this practice can treat infections, such as the cold or flu. According to the folk remedy, if you come down with a cold or the flu, all you have to do is slice a red or white onion into rounds, place them on the bottoms of your feet, and put on a pair of socks. Leave the socks on overnight as you sleep. [...] Putting onions in your socks won’t hurt you, but it probably won’t help, either. To get the full benefit from onions and to help your body recover from or prevent an illness, try eating them as part of a diet rich in fruits, vegetables, and whole grains.