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laetrile

laetrile (lā´ətrĬl´), name given to the chemical amygdalin, a substance derived from an extract of the kernels of many fruits, notably apricots, bitter almonds, and peaches. The idea that laetrile might selectively destroy cancer cells was developed by Dr. Ernst T. Krebs, Sr., a German immigrant to the United States, in the 1920s and was later refined by his son Ernst T. Krebs, Jr., who used the name "vitamin B17" for amygdalin and the derivatives of amygdalin that he developed. The Krebses had hypothesized that an enzyme that was more abundant in tumor cells than normal cells acted on laetrile to produce cytotoxic cyanide. (Cyanide is naturally produced in the intestines when laetrile is acted upon by intestinal bacteria.) This hypothesis and several refinements of it were proved to be untrue, as was the younger Krebs's later classification of the substance as a vitamin.

The subject of controversy for many years, laetrile was subjected to much scientific scrutiny in the 1970s. Investigations showed that anecdotal reports of improvement with laetrile were insufficient proof of effectiveness. Clinical trials showed no effectiveness in shrinking tumors, prolonging survival, or improving the quality of the patient's life. Toxicity from cyanide poisoning in some patients, coupled with the drug's ineffectiveness, led the Food and Drug Administration to label laetrile a fraud. Interstate shipment and shipment from other countries are illegal, but it is still legal in some states and in Mexico.

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laetrile

laetrile Name given to an extract of apricot kernels, amygdalin. Claimed as a cancer cure, although there is no supporting evidence, and sometimes called vitamin B17, although there is no evidence that it is a dietary essential or has any metabolic function.

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vitamin B17

vitamin B17 Laetrile; no evidence that it has any physiological function in the body, so not a vitamin.

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Laetrile

Laetrile

Laetrile, alternatively referred to as amygdalin or vitamin B17, has been in use as a healing agent for thousands of years. Claimed by many to be an almost miraculous cure for cancer, Laetrile has been the subject of court battles and controversy for decades. While proponents point to ancient Egyptian and Chinese documents that refer to its therapeutic properties, the medical and pharmaceutical establishment denies that it has any healing properties and is, on the contrary, a toxic compound that can be dangerous to health.

In the 1920s, an immigrant German doctor in San Francisco, Ernst Krebs, created a curative liquid called amygdalin from the extract of apricot kernels. Authorities stopped him from selling his medicine, stating that the cyanide content made it too toxic. Thirty years later Krebs' son, Dr. Ernst Krebs, Jr., formulated a less toxic form of the compound which he named Laetrile. He continued to work on the substance, and by 1970 he had created a derivative compound which he called vitamin B17.

The theory that Laetrile can cure cancer revolves around this new vitamin. Laetrile supporters claim that B17 is a legitimate vitamin, rediscovered by Krebs. Past societies, and many present ones that have a low incidence of cancer, have regularly consumed foods containing B17 as part of their diet. These foods are the kernels found inside the pit of many fruits, including apricots, and many grains and vegetables such as millet, buckwheat, and cassava, which are uncommon in modern urban diets. Cancer, supporters of Laetrile claim, is a vitamin-deficiency disease, caused by a lack of B17. Supplementing B17 in the diet can prevent cancer and shrink existing tumors.Supporters cite a variety of studies, including several at New York's respected Sloane-Kettering Institute, which prove the efficacy of Laetrile in shrinking tumors and prolonging life in animals with cancer.

Opponents of the use of Laetrile, among them the American Cancer Society, challenge the accuracy of the advocates' experiments, calling their research anecdotal and flawed. They have performed their own studies, which show that Laetrile has virtually no success in treating cancer. Though they admit the danger of toxicity is small, they also point to several cases of sickness and even death in small children who have accidentally ingested Laetrile. Opponents insist that B17 is not a necessary vitamin but merely Kreb's concoction, at best useless, at worst harmful. While Laetrile's supporters point to a "propaganda attack" by multinational pharmaceutical companies to quash their natural and holistic cure, the medical establishment calls Laetrile "quackery."

Laetrile has been the focus of extensive litigation for decades. Since its inception, the U.S. government has fought to keep it out of the country, forcing patients in search of Laetrile therapy to seek it at clinics in Mexico and other countries. In 1977, a U.S. District Court ruled that the Food and Drug Administration had illegally seized shipments of Laetrile. That decision was overturned in 1979, but from 1977 to 1987 terminally ill patients could legally obtain Laetrile if they had an affidavit from a doctor allowing it. In 1987, that too was overturned, and, as of the late 1990s, it is illegal to import Laetrile, or to transport it across state lines.

As one of the major causes of death in industrialized countries, cancer is greatly feared in modern society. Many environmentalists and health food advocates blame modern industry with its petrochemical pollutants for causing the upsurge in cancer deaths. Though billions of dollars are spent on research, medical science is still far from prevention or cure of many types of cancer. Because it is used in conjunction with other vitamin therapy and a natural, whole foods diet, Laetrile has great appeal to advocates of holistic health, who have lost faith in the "legitimate" medical establishment. They cite the low cure rates from FDA-approved chemotherapy and radiation cancer treatments, and demand the right to seek their own solutions.

—Tina Gianoulis

Further Reading:

Culbert, Michael. Vitamin B17, Forbidden Weapon Against Cancer: The Fight For Laetrile. New Rochelle, New York, Arlington House, 1974.

Griffin, Edward G. World Without Cancer: The Story of Vitamin B17. Thousand Oaks, California, American Media, 1974.

Herbert, Victor. Nutrition Cultism: Facts and Fictions. Philadelphia, George F. Stickley Company, 1980.

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