Written by Helen Cooke, Helen Seers and the CAM-Cancer Consortium.
Updated December 13, 2011

Laetrile

Abstract and key points

  • Laetrile is an acronym used to describe a purified, semi-synthetic form of Amygdalin, a naturally occurring plant compound.
  • There is no clear evidence that laetrile is effective as an anti-cancer agent.
  • Laetrile is associated with serious safety concerns.

Laetrile is an acronym used to describe a purified, semi-synthetic form of Amygdalin (LAEvorotatory and mandeloniTRILE). Amygdalin is a naturally occurring plant compound that contains sugar and produces cyanide and is found primarily in the kernels of apricots, peaches and bitter almonds and also in plants such as lima beans, clover and sorghum.

The main active cancer-killing ingredient of Laetrile is thought to be cyanide, this has caused serious concerns over toxicity. Laetrile is reported to be an anti-cancer treatment or even cure. It was at the height of its popularity in the 1970s and 1980s, and has since been rejected by the scientific community after a phase II controlled clinical trial in 1982 which found no evidence for the efficacy of laetrile and highlighted safety concerns.

There is no clear evidence that laetrile is effective as an anti-cancer agent.

Laetrile/Amygdalin/B17 is associated with potential toxic effects at certain doses (cyanide poisoning) and liver problems.

Citation

Helen Cooke, Helen Seers, CAM-Cancer Consortium. Laetrile [online document]. http://www.cam-cancer.org/CAM-Summaries/Dietary-approaches/Laetrile. December 13, 2011.

Document history

References

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