Controversy about the efficacy of the Gerson therapy continued throughout Gerson's life. In 1946 and 1949, two articles in the Journal of the American Medical Association concluded that the treatment was of no value.[9,10] The National Cancer Institute (NCI) reviewed Gerson's data from ten case histories in 1947 and 50 case histories in 1959. NCI concluded that in most cases, basic criteria for evaluating clinical benefit were not met. NCI concluded that the data demonstrated no benefit. In 1972, the American Cancer Society (ACS) published a statement summarizing the negative assessments of Gerson's treatment. Another statement published by ACS in 1991 concerned various "metabolic therapies" (defined as treatments that depend on changing metabolism through diet, enemas, and supplements given at clinics in Tijuana, Mexico) and reemphasized the lack of scientific evidence on the efficacy of the Gerson regimen.
Gerson died in 1959, leaving behind no systematic way to continue offering his treatment. His malpractice insurance had been canceled in 1953, and in 1958 he was suspended for 2 years from the New York County Medical Society. In 1977, his daughter, Charlotte Gerson Straus, who had continued to lecture widely about the Gerson therapy, cofounded the Gerson Institute with Norman Fritz. Located in San Diego, the Gerson Institute does not own or operate treatment facilities but maintains a licensing program for treatment centers such as the Centro Hospitalario Internacional Pacifico and Mexico's Center for Integrative Medicine and the Gerson Hospital (CHIPSA) in Baja California, Mexico. CHIPSA refers to Max Gerson as the founder of "immunonutrition," their term for Gerson's idea of cleansing the body while building up the immune system through diet and supplementation.
- Gerson M: A Cancer Therapy: Results of Fifty Cases and The Cure of Advanced Cancer by Diet Therapy. San Diego, Calif: The Gerson Institute, 2002.
- US Congress, Office of Technology Assessment.: Unconventional Cancer Treatments. Washington, DC: U.S. Government Printing Office, 1990. OTA-H-405.
- Gerson M: Dietary considerations in malignant neoplastic disease: preliminary report. Rev Gastroenterol 12: 419-25, 1945. Also available online. Last accessed September 22, 2010.
- Gerson M: The cure of advanced cancer by diet therapy: a summary of 30 years of clinical experimentation. Physiol Chem Phys 10 (5): 449-64, 1978.
- Ernst E: Colonic irrigation and the theory of autointoxication: a triumph of ignorance over science. J Clin Gastroenterol 24 (4): 196-8, 1997.
- Gerson C, Walker M: The Gerson Therapy: The Amazing Nutritional Program for Cancer and Other Illnesses. New York, NY: Kensington Publishing Corp, 2001.
- Rothman S, Liebow C, Isenman L: Conservation of digestive enzymes. Physiol Rev 82 (1): 1-18, 2002.
- Isenman L, Liebow C, Rothman S: Transport of proteins across membranes--a paradigm in transition. Biochim Biophys Acta 1241 (3): 341-70, 1995.
- Gerson's cancer treatment. JAMA 132 (11): 645-6, 1946.
- Council on Pharmacy and Chemistry.: Report of the council: cancer and the need for facts. JAMA 139 (2): 93-8, 1949.
- Unproven methods of cancer management. Gerson method of treatment for cancer. CA Cancer J Clin 23 (5): 314-7, 1973 Sep-Oct.
- Questionable cancer practices in Tijuana and other Mexican border clinics. CA Cancer J Clin 41 (5): 310-9, 1991 Sep-Oct.