Detailed guides to painful problems, treatments & more

Popular but Weird & Dangerous Cures

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

Paul Ingraham • 5m read

The colourful history of medicine and quackery is overflowing with people who “swore by” treatments that were unusually bizarre and/or actually hurting them. Faith and ignorance are so powerful that they can easily obscure serious danger.

(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.

The fact that patients swear by us does not mean we are actually helping them. Satisfaction is not the same thing as effectiveness.

Chiropractor Preston Long, author of Chiropractic Fraud and Abuse: An Insider's Lament

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?

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 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

About Paul Ingraham

Headshot of Paul Ingraham, short hair, neat beard, suit jacket.

I am a science writer in Vancouver, Canada. I was a Registered Massage Therapist for a decade and the assistant editor of for several years. I’ve had many injuries as a runner and ultimate player, and I’ve been a chronic pain patient myself since 2015. Full bio. See you on Facebook or Twitter, or subscribe:

What’s new in this article?

2019 — Added drinking bleach, inspired by the FDA’s bizarre warning about it.

2012 — Publication.


  1. Ironically, bloodletting is actually an excellent example of medicine accepting a seemingly outlandish “alternative” treatment … if it actually works. And bloodletting is actually effective for one (rare) condition: hemochromatosis. That’s a build-up of iron in the blood, caused mostly by either a genetic disorder or repeated blood transfusion. It’s serious, and you treat it by basically diluting the blood: bloodletting! More formally, phlebotomy. But the exception proves the rule: bloodletting isn’t actually helpful for 99% of what it was used for historically. Hat tip to med student Bobby Hannum for the excellent footnote suggestion.
  2. Mole B. People are still drinking bleach—and vomiting and pooping their guts out. Aug 14, 2019.
  3. Allen L. Excuse me, exactly how does that work? Hocus pocus in holistic healthcare. self-published; 2014.


linking guide

1,200 words