Why would someone intentionally poison themselves with cyanide thinking it is good for their health? That is the question raised by a recent article in the medical journal BMJ. They report the case of an otherwise-healthy 67-year old man who was found to be hypoxic (low blood oxygen) while being monitored during anesthesia for a routine procedure. They report:

Postoperatively, the patient admitted to daily self-prescription of apricot kernel extract for a period of 5 years. Apricot kernel is a commonly taken extract used for a range of ailments, and is associated with cyanide toxicity, which was confirmed through blood analysis.

It’s easy to simply blame this gentleman for his own cyanide toxicity, and he does shoulder personal responsibility, but at the same time he is a victim in important ways. He is a victim of the government, which inadequately regulates “supplements” allowing for what are essentially poisons to be sold with the promise of health benefits. He is a victim of the supplement industry which essentially lies to the public and distorts science in order to create a market for their mostly fraudulent products. He is a victim of the medical establishment and academia who have not taken this issue seriously enough. And he is a victim of the culture that has bought into an irrational fetish with all things “natural.”

His decision to slowly poison himself with cyanide, in other words, was not made in a vacuum.

The story of amygdalin

The history of belief in cyanide compounds derived from apricot pits goes back a long way, to 1830. Here is a good summary from Dr. Benjamin Wilson, writing for Quackwatch:

Laetrile is the trade name for laevo-mandelonitrile-beta-glucuronoside, a substance allegedly synthesized by Ernst T. Krebs, Jr., and registered with the U.S. Patent Office for the treatment of “disorders of intestinal fermentation.” This compound is chemically related to amygdalin, a substance found naturally in the pits of apricots and various other fruits. Most proponents of Laetrile for the treatment of cancer use the terms “Laetrile” and amygdalin interchangeably.

Amygdalin was originally isolated in 1830 by two French chemists. In the presence of certain enzymes, amygdalin breaks down into glucose, benzaldehyde, and hydrogen cyanide (which is poisonous). It was tried as an anticancer agent in Germany in 1892, but was discarded as ineffective and too toxic for that purpose. During the early 1950s, Ernst T. Krebs, Sr., M.D., and his son Ernst, Jr., began using a “purified” form of amygdalin to treat cancer patients. Since that time scientists have tested substances called “Laetrile” in more than 20 animal tumor models as well as in humans and found no benefit either alone or together with other substances. Along the way its proponents have varied their claims about Laetrile’s origin, chemical structure, mechanism of action, and therapeutic effects. Its place in history is assured, however, as a focus of political activities intended to abolish the laws protecting Americans from quackery.

A 2015 Cochrane systematic review of clinical studies of amygdalin/Laetrile for cancer concluded:

The claims that laetrile or amygdalin have beneficial effects for cancer patients are not currently supported by sound clinical data. There is a considerable risk of serious adverse effects from cyanide poisoning after laetrile or amygdalin, especially after oral ingestion. The risk-benefit balance of laetrile or amygdalin as a treatment for cancer is therefore unambiguously negative.

It’s good to see a Cochrane review that is unafraid to use words like “unambiguously” or fall victim to the gratuitous, “more research is needed,” when it clearly isn’t.

What this story indicates is that once a suggestion is made within the popular culture that a substance may be a useful treatment, it rarely goes away completely. Further, the modern alternative medicine/supplement industry is adept at recycling old snake oil claims. Sometimes they repackage them with more modern marketing lingo, but it is amazing how old most of the marketing strategy really is. It still mostly revolves around a reverence for anything “natural” and a distrust of establishment medicine.

It was also interesting to learn that promotion of laetrile as a fake cancer cure may have significantly contributed to the modern alternative medicine movement itself. Obviously we can’t know how things would have gone if laetrile were not in the picture, but its role is pretty clear. Organizations mobilized to promote health freedom focusing on laetrile, but then expanding to health freedom and alternative medicine in general.

Eric Hovind gets involved

Another interesting aspect of the amygdalin story is that it has become a great example of the intermingling of faith and alternative medicine. CAM, we have long argued, is a faith-based system. It is ultimately about promoting spirituality and mysticism as medicine. At times it tries to disguise itself as scientific, but that is always a ruse.

CAM largely promotes Eastern mysticism, because it is exotic and does not immediately seem like a religion to Westerners, but it is. Reiki, for example, is basically faith healing. But Western fundamentalist religions don’t want to be left out – they already have promotion of pseudoscience and conspiracy theories in their skill set. Eric Hovind has now made himself an excellent example of this.

Hovind’s God Quest, Inc, doing business as Creation Today, until recently was selling laetrile as a cancer cure. Laetrile was given the fake name, “vitamin B17” to make it seem more natural, when of course it is not a vitamin at all. Hovind was selling B17 amygdalin, raw bitter apricot seeds (which contain amygdalin) and the quack book, World Without Cancer, which promotes both laetrile and the conspiracy theory that the medical establishment is hiding a cure for cancer.

His website selling this poison deceptively proclaims:

Learn and experience first hand from these important and popular resources, the results that could occur if the solution should be found in a simple vitamin!


These kernels are fresh, high quality, California grown apricot kernels which have not been steamed or cooked and, thus, retain their full complement of natural nutrients. God has blessed us with B17 in abundance!

This is a complete intermingling of a reverence for all things natural and fundamentalist religious faith. God created natural supplements for our benefit.

I said that Hovind was selling this snake oil until recently because he had to stop due to FDA action. They sent him a letter, which itself is very revealing, citing him for selling laetrile with illegal health claims. In the US the claims make the drug – in other words, part of what defines a substance as a drug under FDA control is that it is claimed to treat an actual disease. Hovind was careful not to make any explicit disease claims on his website, as you can see above. He implies claims, but never says that laetrile treats cancer.

However, he made the mistake of packaging laetrile with the book, which does clearly make disease claims. The FDA letter states:

In addition, along with offering your B17 Amygdalin and Bitter Raw Apricot Seeds by Apricot Power for sale through your website at, your website offers for sale the book, World Without Cancer: The Story of Vitamin B17,which includes claims relating to Vitamin B17, an ingredient in your products B17 Amygdalin and Bitter Raw Apricot Seeds by Apricot Power.

For now Hovind has simply stopped selling laetrile on his Creation Today website, citing the FDA warning. I suspect, however, that he is looking into just selling the laetrile without the book. This should not work, but it might. He has already established a market for his snake oil by linking it to explicit claims that it is a cancer cure. Even before him, this link has been made clear.

No one would take amygdalin and risk poisoning themselves with cyanide unless they had been convinced by such claims. You cannot separate the two. However, current regulations allow for this fiction. You can sell herbal drugs and even toxins as if they are dietary supplements as long as you are coy about your health claims. More explicit health claims can be made elsewhere, but you have to be careful not to clearly link the two in your marketing.

It’s all a game, one rigged in favor of the supplement industry and against the consumer. The lack of outrage by consumer protection organizations and the medical establishment is by itself a scandal. I doubt the BMJ article will move the needle significantly.


Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also has produced two courses with The Great Courses, and published a book on critical thinking - also called The Skeptics Guide to the Universe.