Gerson Therapy

Gerson Therapy: Initially, Gerson used his therapy as a treatment for migraine headaches and tuberculosis. In 1928, he began to use it as a supposed treatment for cancer.

Gerson Therapy is based on the belief that disease is caused by the accumulation of unspecified toxins, and attempts to treat the disease by having patients consume a predominantly vegetarian diet including hourly glasses of organic juice and various dietary supplements. Animal proteins are excluded from the diet under the unproven premise that tumors develop as a result of pancreatic enzyme deficiency. In addition, patients receive enemas of coffee, castor oil and sometimes hydrogen peroxide or ozone.

After Gerson's death, his daughter Charlotte Gerson continued to promote the therapy, founding the "Gerson Institute" in 1977. The original protocol also included raw calf's liver taken orally, but this practice was discontinued in the 1980s after ten patients were hospitalized (five of them comatose) from January 1979 to March 1981 in San Diego, California, area hospitals due to infection with the rare bacteria Campylobacter fetus. This infection was seen only in those following Gerson-type therapy with raw liver (no other cases of patients having sepsis with this microbe, a pathogen in cattle, had been reported to Centers for Disease Control and Prevention in the previous two years). Nine of ten hospitalized patients had been treated in Tijuana, Mexico; the tenth followed Gerson therapy at home. One of these patients who had metastatic melanoma died within a week of his septic episode. Many of the patients had low sodium levels, thought to be associated with the very low sodium Gerson diet.

Gerson's therapy has not been independently tested or subjected to randomized controlled trials, and thus is illegal to market in the United States. The Gerson Institute promotes the therapy by citing patient testimonials and other anecdotal evidence. Gerson published a book discussing the alleged success of the therapy in 50 patients, but a review by the U.S. National Cancer Institute was unable to find any evidence that Gerson's claims were accurate. The NCI found that no in vivo animal studies had been conducted. Similarly, case series by Gerson Institute staff published in the alternative medical literature suffered from methodological flaws, and no independent entity has been able to reproduce the claims.

Attempts to independently check the results of the therapy have been negative. A group of 13 patients sickened by elements of the Gerson Therapy were evaluated in hospitals in San Diego in the early 1980s; all 13 were found to still have active cancer. An investigation by Quackwatch found that the institute's claims of cure were based not on actual documentation of survival, but on "a combination of the doctor's estimate that the departing patient has a 'reasonable chance of surviving', plus feelings that the Institute staff have about the status of people who call in".

A 1994 article in the Journal of Naturopathic Medicine attempted to follow 39 Gerson patients in Tijuana. Patient interviews were used to confirm the existence and stage of cancer; most patients were unaware of the stage of their tumor, and medical records were not available. Most patients were lost to follow-up; of the patients successfully followed, 10 died and six were alive at their last follow-up. Review of this study pointed out its "obvious flaws", including "the majority of patients lost to follow-up, lack of access to detailed medical records, and reliance upon patients for disease stage information"; the authors themselves regarded the results as unclear.

The American Cancer Society reported that "[t]here is no reliable scientific evidence that Gerson therapy is effective in treating cancer, and the principles behind it are not widely accepted by the medical community. It is not approved for use in the United States." In 1947, the National Cancer Institute reviewed 10 claimed cures submitted by Gerson; however, all of the patients were receiving standard anticancer treatment simultaneously, making it impossible to determine what effect, if any, was due to Gerson's therapy. A review of the Gerson Therapy by Memorial Sloan-Kettering Cancer Center concluded: "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". In 1959, the National Cancer Institute (NCI) again reviewed cases of patients treated by Gerson. The NCI found that the available information did not prove the regimen had benefit. Cancer Research UK states that "Available scientific evidence does not support any claims that Gerson therapy can treat cancer [...] Gerson therapy can be very harmful to your health."

Gerson therapy can lead to several significant health problems. Serious illness and death have occurred as a direct result of some portions of the treatment, including severe electrolyte imbalances. Continued use of enemas may weaken the colon's normal function, causing or worsening constipation and colitis. Other complications have included dehydration, serious infections and severe bleeding.

The therapy may be especially hazardous to pregnant or breast-feeding women.

Coffee enemas have contributed to the deaths of at least three people in the United States. Coffee enemas "can cause colitis (inflammation of the bowel), fluid and electrolyte imbalances, and in some cases septicemia". The recommended diet may not be nutritionally adequate. The diet has been blamed for the deaths of patients who substituted it for standard medical care.

Relying on the therapy alone while avoiding or delaying conventional medical care for cancer has serious health consequences. Jessica Ainscough, better known as "The Wellness Warrior", was a major proponent of the Gerson diet after her diagnosis with cancer. She rejected medical treatment and followed the diet strictly, documenting her progress in a popular blog. She died from the cancer in February 2015, aged 30.