What is it that makes chicken soup the most comforting of comfort foods? Does it really have any disease-fighting qualities that aren’t psychological?

My husband, Peter, is a dentist. For years I’ve made chicken soup that he gives to his patients undergoing oral surgery. The soup is as basic as can be: just flavorful chicken broth with a little well-cooked rice. Peter began giving it to his patients as a response to questions about what they could and should eat when restricted to a liquid diet. But he soon realized the soup does more than that. Patients’ mouths may be swollen and they may be experiencing a degree of discomfort, but that quart canning jar filled with homemade chicken soup makes them feel good — good that their dentist understands what they’re going through and cares about them.

Even some animals can appreciate chicken soup. Last October, the Associated Press reported that Chinese zookeepers were feeding two three-year-old panda cubs — “Hope” and “Greatness” — chicken soup to reduce their stress. The pandas, which had been relocated after the Sichuan province earthquake, were exhausted after thousands of tourists had clamored for their attention during a weeklong holiday. “They had been getting less sleep,” an official told the AP, “and they had to run around more. We felt it would be good to give them the soup because they were fatigued and had a bit of shock.” Reportedly the panda cubs “loved” the chicken soup and perked up.

Chicken soup has been considered a curative since earliest recorded history. Ancient Egyptians used it as a remedy for the common cold. In the 10th century, the Babylonian Avicenna, known as “the Prince of Physicians,” recommended it. In the 12th century, the Jewish physician Maimonides wrote that chicken soup “is of benefit against chronic fevers…and also aids the cough,” recommending its “virtue in rectifying corrupted humors.”

Maimonides seems to have regarded chicken soup as something of a cure-all, not only prescribing it for convalescents, but also for hemorrrhoid sufferers (we can only speculate how it was used) and as treatment for the early stages of leprosy.

Interestingly, modern scientific research has found some basis for chicken soup’s curative reputation — although not, at least as far I could discover, for hemorrhoids or leprosy.

Physician Irwin Ziment, pulmonary specialist and UCLA medical school professor, has reported that chicken soup contains drug-like components similar to ingredients in modern