... People’s fear of sweating is usually far greater than how much they actually perspire, said Dr. David Bank, a dermatologist in Mount Kisco, N.Y. “Fewer than 5 percent of people really suffer from debilitating sweating,” he said. “That’s called hyperhidrosis. But I’ve found 50 percent of individuals think they sweat excessively.”

People who suffer from extreme malodor are even rarer, said George Preti, an analytical organic chemist who studies body odor at the Monell Chemical Senses Center, a nonprofit research institute financed in part by corporations (including manufacturers of deodorant and antiperspirant).

So why the fear of dampness and smell?

Gabrielle Glaser, the author of “The Nose: A Profile of Sex, Beauty, and Survival,” argues that the phenomenon started in the early 1900s when marketers urged immigrants to eliminate their body odor to become more American.

“If you were new to the country, you wanted to do whatever you could to not offend,” said Ms. Glaser, a former contributor to The New York Times. “During the Depression, the marketing encouraged people to think that they could lessen their anxiety about losing their jobs by making sure that they didn’t stink.”

It almost reads like a Dr. Seuss parable: this magic product had the power to strip immigrants and workers of their individual, fingerprint-like smell — like so many star-bellied Sneetches erasing their identities.