Does an Onion in the Room Stop a Cold or Flu?

Putting onion in socks might sound strange, but many people swear by it as a natural remedy for colds, regularly posting the claim on social media every cold and flu season. The concept is that onions have the ability to absorb bacteria and viruses and, by doing so, can draw germs and toxins out of a sick person or even the air.

To date, there is no evidence to support the claims. The National Onion Association itself states that there is no scientific proof "a cut raw onion can absorb germs or rids the air of toxins and poisons."

This article will explain the origins of the onion-in-socks remedy and why it is unlikely to be of any benefit if you have a cold or flu. On the flip side, it will describe some of the health benefits of onions in bolstering your immune defenses.

Onions As Prevention: Origins of the Remedy

The onion cold remedy, which involves placing sliced onion in the bottom of your socks while asleep, has origins in both medieval healing and traditional Chinese medicine (TCM).

Medieval Origins

The idea that onions can prevent transmittable diseases dates back to the 1500s, according to the National Onion Association. During the bubonic plague, cut onions were placed around homes to keep people from contracting the deadly illness.

At the time, it was believed that all illnesses were spread through the air as clouds of disease known as miasma (derived from the ancient Greek word for "pollution"). Miasma was meant to be something you could smell, and onions, with their distinctive smell, were thought to literally absorb miasma and provide protection.

In medieval Italy, the concept of miasma even gave rise to the term malaria, literally translated as "bad air."

In more recent history, people used onions in a room to provide protection against the 1918 Spanish flu pandemic. In one anecdote, a doctor was said to have ordered his patients to place cut onions in their homes, which he claimed kept them healthy while others around them did not.

Traditional Chinese Medicine

Others contend that the remedy is founded on principles of traditional Chinese medicine. In TCM, the body is said to have 12 major access points known as meridians that form the pathways to each organ in the body. Six of the 12 meridians pass through the feet.

Although these foot meridians are often dormant (mostly because we cover our feet with shoes), their stimulation is thought to deliver health benefits, including improved immunity. It is a principle that drives the practice of foot reflexology.

Some people contend that onions have such a stimulatory effect as they are regarded as a "warming food" in TCM, counteracting the cold and dampness that weakens the immune system. There are few, if any, studies to support the claim.

Why Onions in Socks Don't Work

Some of the claims about onions are loosely based on fact. For one, they do not provide the ideal environment for viruses to multiply or survive; that is a given. With a pH balance of 5.4 to 5.8, onions have mildly acidic properties that are inhospitable to many germs. Those like adenoviruses, the most common cause of colds, thrive in a more neutral environment (around 7.2 pH).

This is not to suggest that onions have strong antiviral or antimicrobial properties; they do not. To effectively kill adenoviruses and other similar respiratory viruses, you need an alkaline solution like bleach that has a pH of 11 to 13.

Neither is there any evidence that onions have any absorption properties specific to viruses, whether those in the body or those in the air. While onions do exert mild antibacterial properties, colds are ultimately caused by viruses and not bacteria.

There is no evidence that onions can draw the virus out of the body or that drawing the viruses to the foot has any benefits in healing colds.

Even within the construct of TCM, the stimulation of meridians in the foot is mainly achieved through needling (acupuncture) and pressure (acupressure).

Moreover, the topical use of onions (Cong Bai) to ease cold symptoms is traditionally delivered as a paste applied to the chest, back, soles, palms, and back of the knees rather than the foot.

Health Benefits of Onion

While there is no proof that putting onions in your socks can help treat or prevent colds, this should not undermine the health benefits of the inexpensive and widely available food.

Onions are low in calories and sugar and contain no fat. Three medium green onions provide all the vitamin K you need on a daily basis, supporting bone health and potentially reducing the risk of osteoporosis.

Green onions are a great source of vitamin A and magnesium which support a strong immune defense and are rich in antioxidants like vitamin C that protect cells from damage caused by unstable molecules known as free radicals.

Onions also contain one the highest concentration of a plant-based compound called quercetin which studies have shown can boost the immune response in the form of increased white blood cell counts (particularly defensive ones called lymphocytes).

This is not to say that eating onions can prevent or treat the common cold; there is no scientific proof of that. Rather, onions can be an important part of a healthy, balanced diet to better support your overall immune health.

Summary

While some people believe that putting onions in socks can speed healing from a cold, there is no evidence that it works. Onions can support your immune health as part of a healthy diet, but they have no direct effect on cold viruses or cannot change the course of the infection in any way.