Many people believe that dampness makes us susceptible to colds and influenza, especially when we get our feet wet. How many times have our mothers made us change damp clothes, lest we catch a cold?
What would Ben Franklin say about the notion that colds come from exposure to wetness?
Here’s what Franklin did say: “The disorder we call a cold … can never by a little addition of moisture hurt a body filled with watery fluids from head to foot.”
During Franklin’s era, it was almost universally believed that cold damp air caused the condition we call a cold, a belief that persists to the present. Indeed, the name “cold” derives from that concept. Towards the middle of the 18th century, when Franklin was at the peak of his influence, a number of thinkers, Franklin among them, concluded that colds and influenza were contagious diseases, similar to smallpox, malaria, and other maladies that swept through colonial North America from time to time.
We have to remember that the notion that germs cause diseases hadn’t yet been proposed in Franklin’s lifetime, even though some experimenters had seen such tiny organisms with primitive microscopes developed in the late 1600s.
As for the notion that dampness caused colds, Franklin pooh-poohed this idea in a 1773-letter to Dr. Benjamin Rush—a prominent Philadelphia physician and signer of the Declaration of Independence. Rush strongly believed that dampness somehow led to colds. Franklin explained to Rush why he didn’t accept this concept. Instead, he concluded that colds were transmitted from one person to another. He said, “I have long been satisfy’d from Observation, that besides the general Colds now termed Influenza’s, which may possibly be spread by Contagion as well as by a particular Quality of the Air, People often catch Cold from one another when shut up together in small close Rooms, Coaches, and so forth, and when sitting near and conversing so as to breathe in each others Transpiration …”
As for the notion that one could catch a cold by becoming wet, Franklin told Dr. Rush:
“Travelling in our severe Winters, I have suffered Cold sometimes to an Extremity only short of Freezing, but this did not make me catch Cold. And for Moisture, I have been in the River every Evening two or three Hours for a Fortnight together, when one would suppose I might imbibe enough of it to take Cold if Humidity could give it; but no such Effect followed: Boys never get Cold by Swimming. Nor are People at Sea, or who live at Bermudas, or St. Helena, where the Air must be ever moist, from the Dashing and Breaking of Waves against their Rocks on all sides, more subject to Colds than those who inhabit Parts of a Continent where the Air is dryest.”
Furthermore, Franklin was convinced that a person’s physical condition was even more important than exposure to the expired breath of others. Here’s how he put it:
“From these Causes, but more from too full Living with too little Exercise, proceed in my Opinion most of the Disorders which for 100 Years past the English have called Colds.”