Ernst Theodore Krebs, Jr. (May 17, 1911 – September 8, 1996), known as Ernst T. Krebs, was an American promoter of 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 preventative and cure. His medical claims about these compounds are not supported by scientific evidence and are widely considered quackery.
Krebs was born in Carson City, Nevada, on May 17, 1911. 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. 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 but was expelled after failing out of his courses. 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. Although he claimed to have a Ph.D. from the University of Illinois, and his supporters often refer to him as "Dr. Krebs," his only doctoral degree was an honorary degree from the now defunct American Christian College in Tulsa, OK, which was a small bible college not accredited to award any advanced degrees. He would later spend two years doing graduate work in anatomy, but was dismissed for "his pursuit of what was deemed unorthodox."
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. Krebs Sr. revived this theory by the embryologist Beard from Scotland to promote one of his cancer cures, chymotrypsin. 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.
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.
Amygdalin and laetrile
Amygdalin, C20H27NO11, is a glycoside initially isolated from the seeds of a cultivar of the almond tree, Prunus dulcis var. amara, also known as bitter almonds, by Pierre-Jean Robiquet 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. It is also not a vitamin, and can cause cyanide poisoning. The promotion of laetrile to treat cancer has been described in the scientific literature as a canonical example of quackery, 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."
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- Young, James, "Laetrile in Historical Perspective", Politics, science, and cancer : the laetrile phenomenon, pp. 11–60 in Markle & Peterson, 1980.
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- Peterson, James C.; Markle, Gerald E., "The Laetrile Phenomenon: An Overview", Politics, science, and cancer : the laetrile phenomenon, p. 6 in Markle & Peterson, 1980.
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- 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.
- Moertel, Charles G.; 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:10.1056/NEJM198201283060403. PMID 7033783.
- 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.
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