Updated: Mar 11, 2020
A common belief is that chicken soup speeds up recovery. Has this been scientifically validated or has it just been passed on from generation to generation? If it's true, then what component of the soup is responsible?
The history of chicken soup
Chicken soup has sometimes been used to symbolize all home remedies, (1) but has been
One of the earliest known references to the purported benefits of this home remedy, known as chicken soup, leads back all the way to the 12th century, where Maimonides recommended chicken soup for many ailments of which respiratory tract symptoms, such as the common cold.
Maimonides was an Egyptian Jewish physician and philosopher, who was very dedicated to his patients, working from morning till night. It was said his views on chicken soup were based on ancient Greek writings. (4), (5)
Now this was a long time ago, where living conditions and access to food was very different from now.
Do we have any modern science that can back up the claims of faster recovery?
Interestingly enough, despite all the purported benefits, there is not a lot of research done on the effects of chicken soup on the common cold.
A lot has been written about it, but if you follow the references through, they all seem to end up in two main studies, (6), (7) which are regurgitated on a regular basis on news sites, in articles and in blogs (like this one).
That's the scientific evidence we have to work with to find out if chicken soup really has healing magic properties.
So, does chicken soup really help?
Before we get to that, we need to understand when we get a cold, why we need to cough, sneeze, or have a runny nose.
Why do we get these symptoms?
First, an infection has to be present. An infection of the mucosal layers within the respiratory tract to be more precise. (7)
These mucosal layers produce mucus.
Yes, we are covered in mucus. But that's actually a good thing.
As we've covered in The Best Ways to Protect Yourself Against Virus Infections Part 1, the mucus moistens and protects the airways, functioning as a barrier to potential pathogens and foreign particles like viruses.
If a virus manages to break through your protective barrier and sets up an illegal camp, the authorities will send out troops to combat these illegal campers.
The campers don't want to go willingly, so force has to be used, which results in chaos and the need for a lot of bandages for the physically wounded and tissues for the emotionally wounded.
In the same way your immune system will send white blood cells to the infected areas to combat the virus infection, which leads to chaos in the form of local inflammation. It is this inflammation which is responsible for the cold symptoms you experience. (7)
White blood cells are essential to clear out an infection, but they can also create damage in the process, especially if they hang around for too long. (8)
Imagine those troops being on their toes the whole time trying to neutralize those campers. A friend of one of the troopers happens to be nearby. He's curious to see what all the fuss is about.
Suddenly he sees his trooper buddy emotionally damaged from all the onslaught that has ensued and wants to offer him a tissue, like any good friend would do. He walks up to him and puts his hand on his buddy's shoulder to show him some comfort. Trooper buddy, who is still full of adrenaline, immediately jumps up in the air and somersault kicks his friend right on the nose.
Somersault trooper didn't mean to hurt his friend, but he still did. White blood cells can, in a similar matter cause damage to surrounding cells and tissues.
What happened in the study was that chicken soup seemed to inhibit the migration of some of the white blood cells to the infection site. Less white blood cells theoretically means a less severe inflammatory response and a relief of symptoms. Why only in theory?
Because the scientists measured all of this in a Petri dish. That's nice, but nicer would be an actual test on people and see how they fare. A Petri dish doesn't mimic the human body that well, since the human body is vastly more complex.
So, that means all our hopes lie in a single study that studied the effects of chicken soup on people with a cold. All the way back from 1978. Thankfully, they made a digital copy. (6)
Hot or Cold?
They tested cold water, hot water and chicken soup on the amount of mucus that can clear out from within the nose.
Cold water had the opposite effect and caused more congestion.
Both hot water and chicken soup had a positive effect. Chicken soup seemed to clear the mucus from the nose better than hot water when looking at absolute numbers, but it turned out 2% worse than hot water in relative numbers.
What does that mean?
One thing we can clearly conclude is that drinking hot fluids helps to clear more mucus, thus relieving some of the cold symptoms. At least temporarily, because after 30 minutes everything went back to 'normal'. There was also no increased airflow within the nasal cavities.
You're likely familiar with the movement of mucus yourself when you drink or eat hot soup.
Especially when you don't have a tissue or napkin nearby, thanks to gravity. Maybe some mucus has accidentally fallen into your soup. You consumed it again, because you support recycling. Good on you.
In theory, the temporary clearing of mucus could potentially help with recovery, because it shortens the contact time of the virus or pathogen, during which it can't multiply, thus inhibiting 'new campers' from penetrating the fence. (6)
What else do we know about chicken soup?
A scientist, who studied chicken soup in respect to allergies and asthma, not the common cold, noted that chicken soup, but also hot tea, can improve the function of little hair like things, called the cilia (see image 2), that help clear the airways. (9)
So far, evidence that chicken soup is something particularly special is lacking.
Hot liquids are helpful
Hot drinks or soups on the other hand do seem to be beneficial.
Drinking a hot fruit-like beverage also seems to be more favorable than drinking the same beverage at room temperature, although in a study that compared these two, EVEN the room temperature beverage seemed to improve some cold symptoms, like cough, runny nose and sneezing.
Hot worked better though, cause it also helped soothe the throat and made one feel less cold.
Interestingly, improved airflow was observed in both groups in this study, but it was thought to be both physiological and psychological. In other words, SOME of the effect was placebo. (10)
Like we've covered in Does "cold" REALLY make you sick? the placebo effect can be quite powerful.
Summary & Conclusion
Is chicken soup anything special?
No evidence suggests such a thing.
But if only chicken soup makes you want to hydrate yourself and get in some nutrition during times you are weaker, then by all means, chicken soup is the way to go for you.
However, any soup would probably work, since we've seen that a hot drink or beverage clearly relieves you, at least temporarily, of some of your cold symptoms.
Although it's not clear whether soup or hot beverages will actually make you recover faster or not.
To quote the lead researcher from the study that compared chicken soup with hot and cold water:
"Does chicken soup cure the cold? Of course not. But does it help people with a cold feel better? I think it does ... and so that's why we give hot fluids, including chicken soup, to people with colds." (11)
If you want to stay on the safe side, make sure your soup includes a variety of vegetables and herbs, that are known for their anti-inflammatory and antioxidant properties, (12), (13), (14), (15) which could reduce the cold symptom causing inflammation.
That can be chicken soup with herbs and vegetables, tomato soup with herbs and vegetables, onion soup with herbs and vegetables, pea soup with herbs and vegetables or just plain vegetable soup with herbs.