Social media post inaccurately claims natural remedy of garlic, onions, thyme, and lemon can replace the flu shot
The flu vaccine is the most effective method for preventing serious complications or illness caused by the influenza virus. While ingredients like garlic, onion, thyme, and lemon possess antioxidants and antimicrobial properties, there is limited evidence to suggest that they prevent or eliminate viral infections. “Natural” remedies actually recommended by medical professionals to accelerate recovery from viral infections are sleep and hydration.
Factually inaccurate: Scientific studies have established that the flu vaccine is safe and effective in people. The same cannot be said of the “natural” remedy promoted in the post, thus the claim that the soup is better than the flu shot isn’t in line with the scientific evidence.
Inadequate support: There is a lack of studies showing that a combination of garlic, onion, thyme, and lemon can prevent or cure viral infections in people.
A recent Facebook post claimed that a soup with ingredients including garlic, onions, thyme, and lemon can act as a natural remedy to replace the flu shot. This claim is not new; variations of it have been circulating since at least 2021 when a viral video claimed that this combination of ingredients could cure COVID-19.
Natural remedies for virus treatment and prevention have been documented for many years. Ancient cultures of Egypt, Greece, Rome, China, and India used garlic for medicinal support. A myth about onions acting as air purifiers by absorbing virus particles has circulated since the 1500s. Thyme was used during medieval times to treat pulmonary illnesses. Lemons were advertised as a cure for influenza during the 1918-1919 flu pandemic.
Regardless of their historical use for medicinal purposes, there is limited clinical evidence to indicate that any of these ingredients have antiviral properties.
Garlic contains allicin, a compound that has demonstrated antibacterial and antiviral properties, but mostly in laboratory settings. While one systematic review found that garlic may help prevent viral infections via evidence from eight randomized controlled clinical trials, the sample sizes for these clinical trials were small, with each study evaluating fewer than 175 participants. The review concluded that more clinical research, particularly long-term cohort studies, would be necessary to draw firmer conclusions about the antiviral properties of garlic.
Raw lemons and onions are both sources of vitamin C, an antioxidant that helps maintain healthy cell function. The notion that vitamin C may prevent viral infections originated with American biochemist Linus Pauling, who published a book in 1970 titled Vitamin C and The Common Cold, suggesting this conclusion. But Pauling’s findings have been questioned by various studies over the years, including this Cochrane systematic review, which found that while vitamin C may reduce duration of illness, it doesn’t impact how likely a person is to get the common cold.
The efficacy and safety of the flu shot, on the other hand, is evaluated annually by the U.S. Centers for Disease Control and Prevention (CDC). While the flu vaccine doesn’t entirely eliminate the risk of flu infection, it reduces the likelihood of contracting the virus and the risk of serious complications or hospitalization from the virus. The World Health Organization publishes its specific recommendations for flu vaccine composition and use each year based on the viral strains anticipated to be most prevalent during that year’s flu season.
It is also important to note that not all viruses are transmitted nor treated in the same way. Norovirus infections, for example, spread through food, water, and surfaces that have been contaminated by microscopic feces or vomit particles from an infected person. Rhinoviruses, which typically cause the common cold, and influenza viruses both spread via touch or airborne droplets—such as when a sick person coughs or sneezes in proximity to a person who isn’t sick.
There are no medications available to treat norovirus or rhinovirus infections. In certain cases of influenza, doctors may prescribe an antiviral medication like Tamiflu to reduce flu symptoms or the risk of contracting the flu in the first place. In these cases, doctors recommend that patients avoid contact with other people, get more rest, and drink more water.
The diverse nature of viruses necessitates tailored approaches to their prevention and treatment. Despite the history behind natural remedies like garlic, onions, lemons, or thyme, there isn’t sufficient scientific evidence to suggest that consuming these ingredients together in a soup protects against the flu and other viral infections.
- 1 – Rivlin RS. (2001). Historical Perspective on the Use of Garlic. The Journal of Nutrition.
- 2 – Bhatwalkar et al. (2021). Antibacterial Properties of Organosulfur Compounds of Garlic (Allium sativum). Frontiers in Microbiology.
- 3 – Rouf et al. (2020). Antiviral potential of garlic (Allium sativum) and its organosulfur compounds: A systematic update of pre-clinical and clinical data. Trends in Food Science & Technology.
- 4 – Hemilä and Chalker. (2013). Vitamin C for preventing and treating the common cold. Cochrane Database of Systematic Reviews.1 – Rivlin RS. (2001). Historical Perspective on the Use of Garlic. The Journal of Nutrition.
- 5 – Minozzi et al. (2022). Comparative efficacy and safety of vaccines to prevent seasonal influenza: A systematic review and network meta-analysis. eClinical Medicine.