Bottom Line: The Gerson regimen does NOT work and is potentially dangerous. The dietary restrictions can cause nutrient deficiencies, coffee enemas can cause dangerous electrolyte imbalances, and the Mexico clinics may not meet U.S. standards. Although diet can be an important part of preventing cancer in the first place, it alone cannot reverse the course of cancer once the damage has been done.
The Gerson regimen was developed by Max Gerson, MD, in the 1940s. It involves a strict metabolic diet that emphasizes fresh fruit and vegetable juice, high carbohydrate and potassium, no sodium or fat, and low animal protein. The diet is often supplemented with digestive enzymes, coffee enemas, and various supplements, including laetrile. This diet is based on the false theory that it addresses the cause of cancer by detoxifying the body and stimulating metabolism so that the body can heal itself. These toxins, Gerson claimed, build up from environmental pollution and processed foods and eventually alter cell metabolism. However, this proposed toxin build-up has never been proven, nor has the diet's ability to remove such toxins from the body.
Coffee enemas are used in several metabolic therapies. Theoretically, coffee enemas might aid excretion from the liver and colon, but no theory has been proven. In addition, coffee enemas can be dangerous when used repeatedly, causing electrolyte imbalances in the blood and impaired nutrient absorption. Because the high levels of fruits and vegetables are eaten raw, they may not be absorbed as easily, especially in patients with GI cancers or chemotherapy-induced GI disorders.
Cancer treatment: The National Cancer Institute and the New York County Medical Society have reviewed several cases of patients treated with the Gerson regimen and have found no evidence that it is effective in treating cancer or any other disease.
A group of British researchers reviewed cases of patients treated with the Gerson regimen and concluded that many patients seemed to be helped psychologically.
An evaluation of cancer survival rates was conducted at a Tijuana clinics where the Gerson regimen is offered, the Centro Hospitalario Internationale (CHIPSA). The researchers did not have access to patients' records due to poor record keeping at the clinic, which limited the study seriously because stage and type of the cancer was not known. After following 18 patients for four to five years, it was found that the average survival was 9 months. Such unimpressive results indicate that the Gerson therapy is not effective in treating late-stage cancer.
Researchers from the Gerson Institute conducted a review of survival of 153 patients with melanoma who were treated with the Gerson regimen at the Centro Hospitalario Internacional del Pacifico (CHIPSA). They found higher survival rates for stage II, III, and IV melanoma, but the results are very flawed for several reasons. As a retrospective study, it could not control precisely which aspects of the therapy patients followed, nor did it specify any prior or concurrent conventional treatments used by the patients, which would significantly change their outcome. Also, because it was sponsored by the same people who run the clinic, its results cannot be considered objective and fair.
The American Cancer Society warns that Gerson therapy can be very harmful to the body.
The alternative medicine clinics in Mexico that offer the Gerson therapy are not subject to F.D.A. standards of quality and efficacy, and therefore may use contaminated or dangerous products.
Metabolic diets like the Gerson Regimen can result in nutrient deficiencies (calcium, vitamins D and B12, protein), anemia, and malabsorption in the intestine.
Coffee enemas, a regular part of the Gerson regimen, can cause electrolyte imbalance, which has resulted in serious infections, dehydration, colitis, constipation, seizures, pleural and pericardial effusions (fluid collecting in the lining around the lungs and heart), and death.
Coma from low sodium levels in the blood has occurred in a handful of patients.
Regimen developed by Max Gerson, MD, involving a strict metabolic diet, coffee enemas, and various supplements, including laetrile, which is illegal in the United States. Currently available at clinics in Mexico and elsewhere. Patients use this therapy to treat cancer, although the Gerson Institute web site identifies 49 cancers and degenerative diseases that have been "cured" with the Gerson regimen. The diet emphasizes fresh fruit and vegetable juice, high carbohydrate and potassium, no sodium or fat, and low animal protein, and is sometimes supplemented with exogenous digestive enzymes. This regimen claims to address the cause of cancer by detoxifying the system and stimulating metabolism so that the body can heal itself (10). Coffee enemas can cause infections, dangerous electrolyte deficiencies, and death (5). Despite proponents' claims of recovery rates as high as 70-90 percent, case reviews by the NCI and New York County Medical Society in 1947 found no evidence of the Gerson diet's benefit in cancer (1). The only large, retrospective review of patient survival in the literature was conducted by the Gerson Research Organization. The American Cancer Society (ACS) warns that the Gerson method can be very harmful (9).
Metabolic diet: Juice from fresh fruits and vegetables, high potassium, high carbohydrate, little animal protein, fat-free, sodium-free diet. Prohibited foods include coffee, berries, nuts, dairy, tap water, bottled, canned or processed foods, and aluminum utensils.
Gerson claims he originally developed the diet to treat his migraines, but found it a successful as a treatment for skin tuberculosis and stomach cancer (7). His therapy is based on the theory that cancer is caused by alteration of cell metabolism by toxic environmental substances and food processing, which changes the sodium and potassium content of foods. Gerson's rationale is that cancer patients have low immunity and generalized tissue damage characterized by decreased intracellular potassium to sodium (K/Na) ratios, and, when their cancer is destroyed, toxic degradation products cause coma and death. His diet increases potassium intake and minimizes sodium consumption in an effort to correct the electrolyte imbalance, repair tissue, and detoxify the liver, while coffee enemas reportedly cause dilation of bile ducts and excretion of toxic breakdown products by the liver and through the colon wall. Supplemental potassium and oxidizing thyroid enzymes are given to introduce oxidation to cancer cells and kill them. None of these claims has been substantiated by scientific research (4)(6).
This regimen has resulted in coma-inducing low levels of sodium. Case reports of deaths from repeated administration of coffee enemas indicate that the practice causes a dangerous decrease in serum electrolytes. Coffee enemas have an osmolality of 62 mOsm/kg; repeated administration increases extravascular fluid volume and may cause electrolyte imbalances and subsequent death (5).
The ease of absorption of the high volumes of raw fruit and vegetables in this diet is questionable, especially in patients with GI cancers or chemotherapy-induced mucosal damage. While elements of the Gerson diet are similar to diet recommendations made by the USDA and the American Cancer Society, metabolic diets are unsuitable for some patients with disseminated or metastatic disease, particularly of the head, neck, and gut (1).
Common: Flu-like symptoms, loss of appetite, perspiration with foul odor, weakness, dizziness, cold sores, fever blisters, high fever, tumor pain, intestinal cramping, diarrhea, and vomiting. (The Gerson handbook claims that these adverse reactions are indicative of response) (1). Common (metabolic diet): Nutrient deficiencies (calcium, vitamins D and B12, protein), anemia, and malabsorption may result from metabolic diets. Reported:Campylobacterfetus sepsis caused by the liver injections was reported in 13 patients using the Gerson therapy between 1980-6; liver injections were subsequently eliminated from the regimen. Coma from low serum sodium (as low as 102 mEq/l) occurred in 5 of these patients (9). Coffee enemas cause electrolyte imbalance, which has resulted in serious infections, dehydration, colitis, constipation, and death. Case Reports (Coffee enemas): Case 1: Multiple seizures and hypokalemia leading to cardiorespiratory arrest, coma, and death were reported after excessive use of coffee enemas (1-4 per hour) for a number of days. Case 2: Death attributable to fluid and electrolyte imbalance causing pleural and pericardial effusions after use of coffee enemas, 4 per day for 8 weeks (5).
In 1947, the National Cancer Institute reviewed 10 "cured" cases, and the New York County Medical Society reviewed 86 medical records and interviewed 10 patients treated with the Gerson therapy. Additionally, the NCI reviewed the 50 cases published in Gerson's book A Cancer Therapy: Results of Fifty Cases. None of these case reviews could find sufficient evidence to show efficacy. In 1989, a best case review and psychological study was conducted by British researchers. They found that some patients were benefitting from the Gerson regimen, but not a clinically significant amount; however, the patients did seem to be helped psychologically by the therapy.
Austin S, Dale EB, Dekadt S. Longterm followup of cancer patients using Contreras, Hoxsey and Gerson therapies. J Naturopathic Med 1994;5:74-6. Small prospective evaluation of survival rates at three Tijuana clinics, including the Gerson Institute's La Gloria Hospital (now Centro Hospitalario Internationale). Patients were interviewed at the clinic regarding location of primary tumor, presence of metastasis, and whether it was biopsy-confirmed. Most patients were unaware of the stage of their cancer, and medical records were not available for review. Patients receiving Gerson therapy (n=38) were queried by mail yearly for 4-5 years or until death; the 20 who did not reply were excluded. Of the 18 evaluable patients, one was alive but not disease-free at 5 years; mean survival time from beginning of study was 9 months. Meaningful statistical analysis and comparison to historical control could not be performed due to the small sample size for each cancer site. Despite the obvious flaws of this study - the majority of patients lost to follow-up and the lack of access to detailed medical records - the authors conclude that the Gerson therapy does not cure late-stage cancer.
Hildenbrand GL, et al. 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. A retrospective review of 5-year survival of 153 white adult melanoma patients treated with the Gerson method at a Centro Hospitalario Internacional del Pacifico, SA (CHIPSA), Tijuana, compared to survival rates reported in medical literature. Out of 249 patients treated for melanoma between 1975-90, charts of only 153 were assessable for both outcome and stage at admission. Patients followed the Gerson regimen, including diet, coffee enemas, and variable additional therapies for an unspecified amount of time. Altogether, 45 (29%) patients lived at least 5 years. Of 14 patients with stage I or II melanoma, none had progression of disease, and all remained free from melanoma for up to 17 years. Of 35 stage III patients, 25 (71%) survived 5 years, compared to the survival rates ranging from 27% to 42% in the literature. Of 104 stage IV patients, 18 were admitted presenting only superficial metastatic disease with no internal metastases, of which 7 (39%) survived 5 to 19 years. This was contrasted to a 6% survival rate in similar cases in a published outcomes analysis by the Eastern Cooperative Oncology Group. None of the 86 patients with advanced metastases survived 5 years. The authors suggest no mechanism of action for the Gerson regimen, but admit the supportive psychosocial environment of the clinics might affect outcomes. A serious flaw in this study is its failure to control for additional variable therapies used by patients, and failure to specify any prior or concurrent conventional treatments used. Because this study only follows 61% of the patients treated at the clinic, there remains the possibility that this is not a comprehensive representation of the therapy's outcomes. The authors claim that the NCI's prior best-case review of the Gerson therapy was flawed in its focus on the outcome of tumor regression, which is not adequately documented at most alternative medical clinics. Though its questionable data are interesting, this study illustrates the need for more comprehensive record keeping at alternative medical clinics. If proponents of such therapies wish them to be evaluated scientifically and considered valid adjuvant treatments, they must provide extensive records (more than simple survival rates) and conduct controlled, prospective studies as evidence.
