Is it safe?
There is concern that people may choose to use this regime as an alternative to chemotherapy, thereby avoiding mainstream treatment. The Gerson Institute does not recommend the use of chemotherapy with the diet since the chemotherapy is seen as a poison in the body, and during detoxification the body would find difficulty in dealing with the level of toxins.1 Several aspects of the Gerson therapy itself have been seen as possible causes of adverse effects. These include: coffee enemas,17 the restrictive nature of the diet, thyroid supplements and also the now disused practice of drinking liver juice. The American Cancer Society and the US National Cancer Institute, do not recommend the use of the Gerson therapy, warning that patients should not turn away from mainstream therapy to rely only on this alternative approach.
Serious illnesses, colitis, electrolyte imbalance and even death have been associated with the use of coffee enemas.17 However, these incidences have not been reported in patients undergoing the Gerson treatment at the clinic. In two isolated cases reported two women in Seattle (one with cancer) died due to the enemas removing potassium from the body leading to serious electrolyte imbalance. In either case enemas were used more frequently than is recommended by the Gerson therapy guidelines. It is thought that continued home use of enemas may weaken the colon’s natural function leading to problems such as constipation and colitis.17
The use of a restricted detoxifying metabolic diet alongside enemas may cause an “inflammatory reaction” which is believed to be part of the healing process.10 Negative symptoms of this inflammatory reaction include dehydration, nausea, diarrhoea, flu-like symptoms and death.18
There are safety concerns over the excessive ingestion of potassium. Those with too much potassium in their blood may suffer from hyperkalemia; symptoms include muscle numbness, tingling, abnormal heart rhythm, paralysis and possible heart failure.19
Calves liver juice
The drinking of calves’ liver juice was removed from the Gerson therapy guidelines in 1989 after a history of it being associated with infection with Campylobacter fetus subspecies fetus.20 An outbreak of this bacterial infection was seen in 1981 which killed nine cancer patients who were thought to be using the Gerson treatment.21,22 After learning of this outbreak staff at the Gerson Institute worked with those at the clinic in Mexico to ensure patient safety and by 1989 the policy of drinking liver juice was altered to receiving crude liver extract injections.
Due to the complex nature of the therapy many interactions with other drugs may occur.
The NCI 23 and ACS (American Cancer Society)18 urge patients to not seek treatment from the Gerson clinic due to a lack of evidence of the anti-cancer effects and also potential hazards associated with the therapy.
CitationHelen Cooke, Helen Seers, CAM-Cancer Consortium. Gerson therapy [online document]. http://www.cam-cancer.org/The-Summaries/Dietary-approaches/Gerson-therapy. April 29, 2016.
Assessed as up to date in April 2016 by Barbara Wider.
Assessed as up to date in January 2015 by Barbara Wider.
Assessed as up to date in August 2013 by Barbara Wider.
Most recent update and revision in September 2012 by Helen Cooke.
Fully revised and updated in August 2011 by Helen Cooke.
Fully revised and updated in November 2009 by Helen Cooke.
Summary first published in July 2005, authored by Helen Seers and Helen Cooke.
- Gerson Institute Homepage [online]. 2012. [accessed 2012 August 31] Available from: URL:http://gerson.org/Programs/findgersonclinic.htm
- Gerson, C & Walker, M. The Gerson Therapy. 60 years of proven success! Kensington Publishing, USA; 2001.
- Green S. A critique of the rationale for cancer treatment with coffee enemas and diet. JAMA. 1992; 268: 3224-3227.
- Revill, J. Now Charles backs coffee cure for cancer, Observer, June 27 2004.
- Personal communication with H. Strauss, representative of the Gerson Institute, 16th August 2004.
- Moss RW, Moss RW. Patient perspectives: Tijuana cancer clinics in the post-NAFTA era. Integrative Cancer Therapies. [Historical Article]. 2005 Mar;4(1):65-86
- Lowell, J. The Gerson Clinic. Nutrition Forum. 1986; 3(2):9-12.
- Hildenbrand, GL, Hildenbrand, LC, Bradford, K, & Cavin, SW. Five-year survival rates of melanoma patients treated by diet therapy after the manner of Gerson: a retrospective review. Altern Ther Health Med. 1995; 1:29-37.
- Ernst, E. The Desktop Guide to Complementary and Alternative Medicine: An Evidence-Based Approach, Mosby, London; 2001.
- U.S. Department of Health and Human Services, Public Health Service, National Institutes of Health, National Cancer Institute, National Cancer Institute Statement, "Unproven Methods: The Gerson Therapy," February 5, 1987.
- Gerson, M. A Cancer Therapy. Results of Fifty Cases, 6th Ed. Bonita, CA: Gerson Institute, 1999.
- Avery, RJ, Office of Cancer Communications, National Cancer Institute, National Institutes of Health, U.S. Department of Health and Human Services, letter to G. Dego, University of London, August 24, 1982.
- Austin, S, Dale, EB, & DeKadt, S. Long-term follow-up of cancer patients using Contreras, Hoxsey and Gerson therapies. Journal of Naturopathic Medicine. 1994; 5(1):74-76
- Reed A, James, N, & Sikora, K. Mexico: juices, coffee enemas, and cancer. Lancet, 1990; 336 (8716):677-678.
- Molassiotis A, Peat P. Surviving against all odds: analysis of 6 case studies of patients with cancer who followed the Gerson therapy. Integrative Cancer Therapies. [Case Reports]. 2007 Mar;6(1):80-8.
- National Cancer Institute. NCI best case series criteria for optimal case studies [website]. http://www.cancer.gov/cam/bestcase_intro.html [accessed 2012 August 31].
- Cassileth B. Gerson regimen. Oncology (Williston Part) 2010; 24(20): 201.
- Eisele, JW, & Reay, DT. Deaths related to coffee enemas, JAMA. 1980; 244: 1608-9.
- Anonymous. Questionable methods of cancer management: 'nutritional' therapies. CA Cancer J Clin. 1993; 43(5):309-19.
- Tobian, L. Dietary sodium chloride and potassium have effects on the pathophysiology of hypertension in humans and animals. American Journal of Clinical Nutrition. 1997; 65: S606- S611.
- Gerson Institute, "Raw Liver Juice Has Been Discontinued," Memo, October 3 1989.
- Ginsberg, MM, Thompson, MA, Peter CR, et al., "Campylobacter Sepsis Associated With 'Nutritional Therapy'--California," M.M.W.R. 1981; 30(24): 294-295.
- National Cancer Institute. Gerson Therapy (PDQ https://www.cancer.gov/about-cancer/treatment/cam/hp/gerson-pdq#section/all [accessed 2016 October 12]
The present documentation has been compiled by the CAM-CANCER Project with all due care and expert knowledge. However, the CAM-CANCER Project provides no assurance, guarantee or promise with regard to the correctness, accuracy, up-to-date status or completeness of the information it contains. This information is designed for health professionals. Readers are strongly advised to discuss the information with their physician. Accordingly, the CAM-CANCER Project shall not be liable for damage or loss caused because anyone relies on the information.