Ernst T. Krebs

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Ernst Theodore Krebs, Jr. (May 17, 1911 – September 8, 1996) was an American biochemist. He is known for promoting various substances as alternative cures for cancer, including pangamic acid and amygdalin. He also co-patented the semi-synthetic chemical compound closely related to amygdalin named laetrile, which was also promoted as a cancer preventitive and cure. His medical claims about these compounds are not supported by scientific evidence and are widely considered quackery.

Biography[edit]

Krebs was born in Carson City, Nevada, on May 17, 1911.[1] His father was Ernst Theodore Krebs, Sr. (September 26, 1876 - January 25, 1970), a physician who promoted a syrup as treatment for various ailments which was later deemed fraudulent, seized, and destroyed, and later promoted the enzyme chymotrypsin as a cancer remedy.[2] Krebs, Jr. would ultimately work closely with his father in promoting Laetrile and pangamic acid.

Krebs attended Hahnemann Medical College for three years, including one year spent repeating the first year[2] but was expelled after failing out of his courses.[3][4] Krebs later attended college in various states including Mississippi, California and Tennessee and ultimately received a Bachelor of Arts degree from the University of Illinois, after failing science courses at the various colleges.[3] Although he claimed to have a Ph.D. from the University of Illinois,[2] and his supporters often refer to him as "Dr. Krebs,"[5] his only doctoral degree was an honorary degree from the now defunct American Christian College in Tulsa, OK,[2] which was a small bible college not accredited to award any advanced degrees.[6] He would later spend two years doing graduate work in anatomy, but was dismissed for "his pursuit of what was deemed unorthodox."[2]

He died at his home in San Francisco, California on September 8, 1996.[7] He was not related to Hans Adolf Krebs, the biochemist known for discovering the Krebs cycle.

Advocacy[edit]

Cancer theory[edit]

Krebs advocated the view, first introduced in 1902 by John Beard and revived by Krebs and his father in the 1940s and 1950s, that all forms of cancer arise from undifferentiated cells called trophoblasts.[8] Krebs Sr. revived this theory by the embryologist Beard from Scotland to promote one of his cancer cures, chymotrypsin.[2] Although this theory had been rejected by cancer researchers, Krebs Jr. nevertheless incorporated this theory as one of the explanations for the mechanism of action for Laetrile against cancer cells as well. This mechanism was subsequently abandoned as he later claimed Laetrile was instead a vitamin.[8]

Pangamic acid[edit]

Main article: Pangamic acid

Pangamic acid, also called "pangamate," and "vitamin B15," is the name given to the chemical compound described as d-gluconodimethylamino acetic acid with the empirical formula C10H19O8N and purportedly isolated from apricot seeds. It was initially promoted by Ernst T. Krebs, Sr. and his son Ernst T. Krebs, Jr. as a medicinal compound for use in treatment of a wide range of diseases. They also termed this chemical "Vitamin B15," though it is not a true vitamin, has no nutritional value, has no known use in the long term treatment of any disease and has been called a "quack remedy." Although a number of compounds labelled "pangamic acid" have been studied or sold, no chemical compound, including those claimed by the Krebses to be pangamic acid, has been scientifically verified to have the characteristics that defined the original description of the compound.[9]

Amygdalin and laetrile[edit]

Main article: Amygdalin

Amygdalin, C20H27NO11, is a glycoside initially isolated from the seeds of the tree Prunus dulcis, also known as bitter almonds, by Pierre-Jean Robiquet[10] and Antoine-François Boutron-Charlard (1796-1879) in 1830, and subsequently investigated by Liebig and Wöhler in 1830, and others.

It was promoted in a modified form called Laetrile as a cancer cure by Ernst T. Krebs, Jr. under the name "Vitamin B17", but studies have found it to be ineffective.[11][12][13] It is also not a vitamin, and can cause cyanide poisoning.[14] The promotion of laetrile to treat cancer has been described in the scientific literature as a canonical example of quackery,[15][16][17] with Irving Lerner of the University of Minnesota describing it as "the slickest, most sophisticated, and certainly the most remunerative cancer quack promotion in medical history."[18]

References[edit]

  1. ^ "Search for: Krebs, Ernst". Rootsweb. California Death Records (citing: Vital Statistics Section, Office of Health Information and Research, The California Department of Health Services). Ancestry.com. Retrieved 2013-08-31. 
  2. ^ a b c d e f Young, James, "Laetrile in Historical Perspective", pp. 11–60  in Markle & Peterson, 1980.
  3. ^ a b Wilson, Benjamin (June 22, 2012). "The Rise and Fall of Laetrile". Quackwatch. Retrieved 2013-08-31. 
  4. ^ Kenward, Michael (January 11, 1979). "Laetrile and the Law". New Scientist. p. 88. 
  5. ^ Petersen, James C.; Markle, Gerald E. (May 1979). "Politics and science in the Laetrile controversy". Social Studies of Science 9 (2): 139–66. doi:10.1177/030631277900900201. PMID 11645793. 
  6. ^ Consumers Union, ed. (1981). "Laetrile: the Political Success of a Scientific Failure". Health Quackery: Consumers Union's Report on False Health Claims, Worthless Remedies, and Unproved Therapies. New York: Holt, Rinehart and Winston. pp. 16–40. ISBN 9780030588983. 
  7. ^ Moss Ralph W. (December 2008). "Enzymes, trophoblasts, and cancer: the afterlife of an idea (1924-2008)". Integrative Cancer Therapies 7 (4): 262–75. doi:10.1177/1534735408326172. PMID 19116222. 
  8. ^ a b Peterson, James C.; Markle, Gerald E., "The Laetrile Phenomenon: An Overview", p. 6  in Markle & Peterson, 1980.
  9. ^ Herbert, Victor (July 1979). "Pangamic acid ("vitamin B15")". The American Journal of Clinical Nutrition 32 (7): 1534–40. PMID 377937. 
  10. ^ "A chronology of significant historical developments in the biological sciences". Botany Online Internet Hypertextbook. University of Hamburg, Department of Biology. 2002-08-18. Retrieved 2007-08-06. 
  11. ^ Ellison, Neil M.; Byar, David P.; Newell, Guy R. (September 1978). "Special report on Laetrile: the NCI Laetrile Review. Results of the National Cancer Institute's retrospective Laetrile analysis". The New England Journal of Medicine 299 (10): 549–52. doi:10.1056/NEJM197809072991013. PMID 683212. 
  12. ^ Moertel, Charles G.; Ames, Matthew M.; Kovach, John S.; Moyer, Thomas P. et al. (February 1981). "A pharmacologic and toxicological study of amygdalin". Journal of the American Medical Association 245 (6): 591–4. doi:10.1001/jama.1981.03310310033018. PMID 7005480. 
  13. ^ Moertel; Fleming, Thomas R.; Rubin, Joseph; Kvols, Larry K. et al. (January 1982). "A clinical trial of amygdalin (Laetrile) in the treatment of human cancer". New England Journal of Medicine 306 (4): 201–6. doi:10.1007/s00520-006-0168-9. PMID 7033783. 
  14. ^ O'Brien, Brian; Quigg, Catherine; Leong, Tim (October 2005). "Severe cyanide toxicity from 'vitamin supplements'". European Journal of Emergency Medicine 12 (5): 257–8. doi:10.1097/00063110-200510000-00014. PMID 16175068. 
  15. ^ Herbert, Victor (May 1979). "Laetrile: The cult of cyanide. Promoting poison for profit". The American Journal of Clinical Nutrition 32 (5): 1121–58. PMID 219680. 
  16. ^ Lerner, Irving J. (February 1984). "The whys of cancer quackery". Cancer 53 (Supplement S3): 815–9. doi:10.1002/1097-0142(19840201)53:3+<815::AID-CNCR2820531334>3.0.CO;2-U. PMID 6362828. 
  17. ^ Nightingale, Stuart L. (1984). "Laetrile: The regulatory challenge of an unproven remedy". Public Health Reports 99 (4): 333–8. PMC 1424606. PMID 6431478. 
  18. ^ Lerner, Irving J. (1981). "Laetrile: A lesson in cancer quackery". CA – A Cancer Journal for Clinicians 31 (2): 91–5. doi:10.3322/canjclin.31.2.91. PMID 6781723.