Amygdalin: What is it? Uses, Side Effects, Safety Concerns, Interaction, Research, and Alternatives

It is a cyanogenic glycoside found in the pits of many fruits, raw nuts, and other plants such as lima beans, clover, and sorghum.

It is used to make laetrile (a compound said to help treat cancer ).

Although it is often called vitamin B17 in the non-specialist literature, amygdalin is not recognized as a vitamin by some nutritional health agencies. Laetrile was administered orally and intravenously with different pharmacokinetic and toxicity profiles.

Laetrile became a popular alternative cancer therapy in the 1950s and remained so until the 1980s. Currently, its sale is prohibited by the FDA. However, products labeled as containing laetrile can be easily purchased online.

When ingested orally, laetrile can be hydrolyzed by intestinal beta-glucosidase to produce hydrocyanic acid, benzaldehyde, and glucose. The enzymatic activity of beta-glucosidase, and therefore the rate of cyanide production, can increase under various conditions, including the presence of vitamin C.

Cyanide poisoning signs and symptoms have been reported both in individual cancer patients who ingested laetrile-containing products and in patients enrolled in oral laetrile clinical trials.

Uses for vitamin B17

Laetrile is often said to treat cancer naturally. The Food and Drug Administration does not approve it as a treatment for cancer or other medical conditions.


Some proponents of laetrile suggest that cancer occurs due to a vitamin deficiency. Such advocates claim that consumption of the so-called vitamin B17 can reverse this deficiency and, in turn, aid in the treatment or prevention of cancer.

However, as the National Cancer Institute (NCI) states, there is no evidence that the body needs laetrile or that laetrile can act as a vitamin in animals or humans.

Laetrile also claims to protect against diseases like high blood pressure and arthritis.

Side effects and safety concerns

Amygdalin produces cyanide, which is a toxic substance. Cyanide is believed to be a primary cancer-fighting component. The cyanide released in the body by these substances kills cancer cells.

Developed in the United States in the 1950s, laetrile is said to act as a non-toxic form of amygdalin. Still, laetrile has triggered several side effects similar to cyanide poisoning.

The use of laetrile is associated with the following side effects:

  • The blue coloration of the skin.
  • Confusion.
  • Difficulty in walking.
  • Dizziness
  • Drooping upper eyelids.
  • Headache.
  • Hepatic injury.
  • Low blood pressure.
  • Sickness.
  • Nerve damage
  • Vomiting

Cyanide poisoning can be life-threatening and lead to death.

According to some studies, the use of laetrile is also associated with an increased risk of coma or death.


An interaction of amygdalin with vitamin C.

There is concern that vitamin C may increase the amount of cyanide released by laetrile in the body and, as a result, increase the risk of toxicity.

Research on vitamin B17

Claims that laetrile or amygdalin may benefit cancer patients are not supported by robust clinical data, according to a report published in the Cochrane Database of Systematic Reviews in 2011.

For this report, the scientists analyzed 69 previously published studies evaluating the purportedly anticancer effects and potential adverse effects of laetrile and amygdalin. However, none of these studies turned out to be rigorous enough to meet the reviewers’ criteria.

Studies state that the “risk-benefit balance of laetrile or amygdalin as a cancer treatment is unequivocally negative.”

In other preliminary studies published in recent years, researchers have observed that amygdalin may have some anticancer properties.

A study published in 2013, for example, indicates that tonsillar may protect against cervical cancer.

In tests on human cells, the researchers found that tonsillar can fight cervical cancer by inducing apoptosis (a type of programmed cell death essential to stop the proliferation of cancer cells).

Additionally, two preliminary studies published in 2014 found that tonsillar can fight bladder cancer by blocking tumor growth.

More research is needed before recommending tonsils for cancer prevention or treatment.

Alternatives to vitamin B17

While there is no known way to prevent cancer, certain practices can help reduce cancer risk. These practices include:

  • Avoid smoking and using tobacco.
  • Get screened for precancerous conditions.
  • Follow a healthy diet.
  • Get regular exercise.
  • Keep a healthy weight.

If you consider using vitamin B17 for the prevention or treatment of cancer, it is crucial to consult your doctor first. Treating yourself and avoiding or delaying standard care can have serious consequences.