Do we need to put onion on our feet overnight? No, that's not true: A number of websites and videos claim placing a sliced onion in your sock while you sleep delivers miraculous health benefits, including detoxifying your blood and making your feet smell better, but there is no evidence the process does that.
The claims have circulated on social media for several years and they continue to be shared, including a post (archived here) with a video published on September 9, 2018 under the title "Why do we need to put onion on our feet overnight? She places an onion in her sock and goes to bed.". It opened:
This is why you should put a slice of onion on the sole of your foot before you go to bed:This unusual method will literally heal you in your sleep.Take a red or white onion and cut it into flat slices.You want to make sure the onion slices can easily be applied to the bottom of your feet.Place the onion slice on the bottom of your feet and put on a pair of socks to keep them in place.That's it! As you sleep, the healing properties of the onion will sleep into your skin and absorb unwanted toxins that can make you sick.It will also work to purify the air in your bedroom and eliminate bacteria.
This is what social media users saw:
This video summarizes the purported health benefits of sleeping with a sliced onion in your sock:
Onions remove foot odorOnions have strong anti-bacterial and anti-fungal properties. If you struggle with foot odor, this remedy can help!Onions purify your bloodWhile the onion is next to your foot, phosphoric acid is released. It enters your bloodstream and helps to purify the blood running through your veins.Onions support the immune systemThanks to the anti-bacterial and anti-viral properties of onions, your immune system becomes better prepared to fight off infections and inflammation immune system.Onions purify the air
You're probably don't bring onions into your bedroom on a regular basis, but this remedy can actually help clean the air while you sleep. The onions will work to purify the air by riding it of toxins and chemicals.
The amazing claims can be traced back at least five years online, including this March 2015barticle titled "This is What Happens When You Put Cut Up Onions in Your Socks While You Sleep" that includes almost identical wording to the recent video scripts.
How do we know this is bogus? Because the people who know onions best -- the National Onion Association -- confirmed it on their website:
Q: Can raw onion prevent the flu?
A: There is no scientific evidence that a cut raw onion absorbs germs or rids the air of toxins/poisons. A wives tale that dates back as far as the 1500s claims that placing a cut raw onion in rooms throughout a residence could protect its occupants from getting the bubonic plague. Long before germs were discovered, the dominant belief was contagious diseases were spread by miasma, or "noxious air."
While false, this belief remained part of folk medicine through the 19th century claiming to ward off epidemics like smallpox, influenza, and other "infectious fevers."
Want to know what it is really like to sleep with sliced onions in your socks? This lady can tell you it was not nice: