There are concerns that Gerson therapy is dangerous because it can cause electrolyte imbalance and hyperkalemia. Safety concerns also relate to the use of coffee enemas while undergoing Gerson therapy, and there are case reports of some patients dying, reports the National Cancer Institute.
Literature reports three deaths may be associated with the use coffee enemas as a part of Gerson therapy. The stool and blood of one patient who died produced cultures of Salmonella enteritidis and Campylobacter fetus. However, because further tests were not performed, it is unknown if coffee enema use caused death, states the National Cancer Institute.
Autopsies, which showed no active inflammation of the colons of two deceased patients, subsequently reported that electrolyte imbalance caused the deaths. Additionally, a case report of electrolyte imbalance that did not result in death describes a patient who developed high blood potassium while undergoing Gerson therapy, states the National Cancer Institute. High blood potassium can be fatal, according to MedicineNet.