Popular but Weird and Dangerous Cures

The most dangerous, strange and yet popular snake oils and “treatments” in history, and why anecdotes and testimonials cannot be trusted

650 words, published May 19th, 2012, updated Dec 19th, 2012
by Paul Ingraham, Vancouver, Canada

The colorful history of medicine and quackery is overflowing with people who “swore by” treatments that were unusually bizarre and/or perilous.

Bloodletting was popular almost until the 20th century, despite being relentlessly harmful.
Some of the most lethal “cures” in history were inspired by the discovery of radiation.
People happily drank metals like mercury and silver.
Even drinking urine had near fad status for a while!
They tried to purge disease with sulfuric acid.
They tried to stimulate their vitality (and virility) with powerful electric shocks.
Women were sold Lysol as a douche … and women actually went along with it for a while.
Voluntary lobotomy may be the craziest of them all: it was a popular treatment for all kinds of psychiatric disorders, and at least fifty thousand people volunteered to have their brains lanced.

(And that’s not all! For some other colourful examples, see The 10 Most Insane Medical Practices in History.)

All of these terrible treatments, and many more obscure examples, had many fans and enthusiastic testimonials. People paid for them, believe in them, loved them, swore by them — that is how misleading testimonials can be. People believe what they want to believe.

Medieval European bloodletting tools.

Medieval European bloodletting tools.

How do we get fooled?

It’s easy to dismiss the examples above as historical oddities, but in fact people today still believe in many snake oils, some of which will seem bizarre to people in a hundred years — and some will still be going strong. But why do we believe in things that don’t really work, or even hurt us? How do we get fooled?

Most problems eventually resolve on their own right around the same time we’re getting desperate and trying long-shot cures — the Darkest Before Dawn Effect. The snake oil gets the credit instead of natural healing.
People are often doing more than one therapy at once, and we give credit to the wrong one.
Humans are naturally suggestible, as you can see at any hypnosis show: we believe what we are told, sometimes to the point of absurdity.
Sometimes we believe that a cure worked for a problem we never actually had in the first place — which makes it easy to cure.

Our hopes and wishes make us remember anything that confirms what we want to believe, and ignore everything else (Confirmation Bias).
We never want to admit, to anyone else but even to ourselves, that we’ve wasted our money.
We want to be special and “in the know.”
We want to please (especially authority figures and health care professionals), so we say nice things, and it’s easy: after all, half of all recoveries go better than average! (I was fascinated at how eager my massage therapy clients were to attribute any improvement to my “magic hands.”)
Anything nice or optimistic that we say, we start to believe, because a basic principle of human nature is that “saying is believing.”
Our memories and senses are notoriously unreliable — ask any judge or lawyer. There are many famous examples of seemingly reliable testimony later proven wrong by hard evidence.

And more! All of which is why there is no cure so ridiculous that someone doesn’t swear by it, like dogs swearing that barking prevents death by mailman.show Dr. Mark Crislip said that the three most dangerous words in medicine are in my experience. Even most professionals don’t understand the limits of anecdotal evidence. “Sometimes we get it wrong,” points out Dr. Harriet Hall, The SkepDoc. Her explanation of how we get fooled is one of the best and clearest available: Why We Need Science: “I saw it with my own eyes” Is Not Enough.

If anecdotal evidence were actually reliable, then most folk medicine would still be the best medicine available today.

It is the natural tendency of the ignorant to believe what is not true. In order to overcome that tendency it is not sufficient to exhibit the true; it is also necessary to expose and announce the false.
HL Mencken