Preparing a bowl of chicken soup for a loved one when they’re sick has been a common practice throughout the world for centuries. Today, generations from virtually every culture swear to the benefits of chicken soup. In the US, the dish is typically made with noodles, but different cultures prepare the soothing remedy their own way.
Chicken soup as a therapy can be traced back to 60 AD and Pedanius Dioscorides, an army surgeon who served under the Roman emperor Nero, and whose five-volume medical encyclopedia was consulted by early healers for more than a millennium. But the origins of chicken soup go back thousands of years earlier, to ancient China.
So, with cold and flu season in full swing, it’s worth asking: Is there any science to back the belief that it helps? Or does chicken soup serve as just a comforting placebo, that is, providing psychological benefit while we’re sick, without an actual therapeutic benefit?
As a registered dietitian and professor of dietetics and nutrition, I’m well aware of the appeal of chicken soup: the warmth of the broth and the rich, savory flavors of the chicken, vegetables, and noodles. What gives the soup that distinctive taste is “umami” – the fifth category of taste sensations, along with sweet, salty, sour, and bitter. It is often described as having a “meaty” taste.
The notion that chicken soup is an elixir goes back centuries.
Improved appetite, better digestion
All that makes sense, because amino acids are the building blocks of proteins, and the amino acid glutamate is found in foods with the umami taste. Not all umami foods are meat or poultry, however; cheese, mushrooms, miso, and soy sauce have it too.
Studies show that taste, it turns out, is critical to the healing properties of chicken soup. When I see patients with upper respiratory illnesses, I notice many of them are suddenly eating less or not eating at all. This is because acute illnesses ignite an inflammatory response that can decrease your appetite. Not feeling like eating means you’re unlikely to get the nutrition you need, which is hardly an optimal recipe for immune health and recovery from illness.
But evidence suggests that the umami taste in chicken soup may help spur a bigger appetite. Participants in one study said they felt hungrier after their first taste of a soup with umami flavor added in by researchers.
Other studies say umami may also improve nutrient digestion. Once our brains sense umami through the taste receptors on our tongues, our bodies prime our digestive tracts to absorb protein more easily.
This can reduce gastrointestinal symptoms, which many people experience when they’re under the weather. Although most people don’t associate upper respiratory infections with gastrointestinal symptoms, research in children has found that the flu virus increased abdominal pain, nausea, vomiting, and diarrhea symptoms.