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Gerson Therapy (PDQ®)     
Last Modified: 09/06/2007
Patient Version
Questions and Answers About the Gerson Therapy

  1. What is the Gerson therapy?

    The Gerson therapy has been used by some people to treat cancer and other diseases. It is based on the role of minerals, enzymes, and other dietary factors. There are 3 key parts to the therapy:

    • Diet: Organic fruits, vegetables, and whole grains to give the body plenty of vitamins, minerals, enzymes, and other nutrients. The fruits and vegetables are low in sodium (salt) and high in potassium.
    • Supplementation: The addition of certain substances to the diet to help correct cell metabolism (the chemical changes that take place in a cell to make energy and basic materials needed for the body's life processes).
    • Detoxification: Treatments, including enemas, to remove toxic (harmful) substances from the body.
  2. What is the history of the discovery and use of the Gerson therapy as a complementary or alternative treatment for cancer?

    The Gerson therapy was named after Dr. Max B. Gerson (1881-1959), who first used it to treat his migraine headaches. In the 1930's, Dr. Gerson’s therapy became known to the public as a treatment for a type of tuberculosis (TB). The Gerson therapy was later used to treat other conditions, including cancer.

  3. What is the theory behind the claim that the Gerson therapy is useful in treating cancer?

    The Gerson therapy is based on the idea that cancer develops when there are changes in cell metabolism because of the buildup of toxic substances in the body. Dr. Gerson said the disease process makes more toxins and the liver becomes overworked. According to Dr. Gerson, people with cancer also have too much sodium and too little potassium in the cells in their bodies, which causes tissue damage and weakened organs.

    The goal of the Gerson therapy is to restore the body to health by repairing the liver and returning the metabolism to its normal state. According to Dr. Gerson, this can be done by removing toxins from the body and building up the immune system with diet and supplements. The enemas are said to widen the bile ducts of the liver so toxins can be released. According to Dr. Gerson, the liver is further overworked as the treatment regimen breaks down cancer cells and rids the body of toxins. Pancreatic enzymes are given to decrease the demands on the weakened liver and pancreas to make enzymes for digestion. An organic diet and nutritional supplements are used to boost the immune system and support the body as the regimen cleans the body of toxins. Foods low in sodium and high in potassium are said to help correct the tissue damage caused by having too much sodium in the cells.

  4. How is the Gerson therapy administered?

    The Gerson therapy requires that the many details of its treatment plan be followed exactly. Some key parts of the regimen include the following:

    • Drinking 13 glasses of juice a day. The juice must be freshly made from organic fruits and vegetables and be taken once every hour.
    • Eating vegetarian meals of organically grown fruits, vegetables, and whole grains.
    • Taking a number of supplements, including:
    • Taking coffee or chamomile enemas regularly to remove toxins from the body.
    • Preparing food without salt, spices, or oils, and without using aluminum cookware or utensils.
  5. Have any preclinical (laboratory or animal) studies been conducted using the Gerson therapy?

    No results of laboratory or animal studies have been published in scientific journals.

  6. Have any clinical trials (research studies with people) of the Gerson therapy been conducted?

    Most of the published information on the use of the Gerson therapy reports on retrospective studies (reviews of past cases). Dr. Gerson published case histories (detailed reports of the diagnosis, treatment, and follow-up of individual patients) of 50 of his patients. He treated several different types of cancer in his practice. The reports include Dr. Gerson's notes, with some X-rays of the patients over time. The follow-up was contact with patients by mail or phone and included anecdotal reports (incomplete descriptions of the medical and treatment histories of one or more patients).

    In 1947 and 1959, the National Cancer Institute (NCI) reviewed the cases of a total of 60 patients treated by Dr. Gerson. The NCI found that the available information did not prove the regimen had benefit.

    The following studies of the Gerson therapy were published:

    • In 1983-1984, a retrospective study of 38 patients treated with the Gerson therapy was done. Medical records were not available to the authors of the study; information came from patient interviews. The study provided no scientific evidence.
    • In 1990, a study of a diet regimen similar to the Gerson therapy was done in Austria. The patients received standard treatment along with the special diet. The authors of the study reported that the diet appeared to help patients live longer than usual and have fewer side effects. The authors said it needed further study.
    • In 1995, a retrospective study of patients at the Gerson Institute was done. The patients had melanoma, colorectal, and ovarian cancers. The study reported that some patients lived longer than usual for patients with these cancers.
    • A case review of 6 patients with metastatic cancer who used the Gerson therapy reported that the regimen helped patients in some ways, both physically and psychologically. Based on these results, the reviewers recommended that clinical trials of the Gerson therapy be conducted.
  7. Have any side effects or risks been reported from use of the Gerson therapy?

    Reports of three deaths that may be related to coffee enemas have been published. Taking too many enemas of any kind can cause changes in normal blood chemistry, chemicals that occur naturally in the body and keep the muscles, heart, and other organs working properly.

  8. Is the Gerson therapy approved by the U.S. Food and Drug Administration (FDA) for use as a cancer treatment in the United States?

    The Gerson therapy has not been approved by the FDA for use as a treatment for cancer or any other disease.

    For most cancer patients, nutrition guidelines include eating a well-balanced diet with plenty of fruits, vegetables, and whole-grain products. However, general guidelines such as these may have to be changed to meet the specific needs of an individual patient. Patients should talk with their health care providers about an appropriate diet to follow. Information about diet during cancer treatment is also available from the Cancer Information Service (1-800-4-CANCER [TTY: 1-800-332-8615]) and in the PDQ summary on Nutrition in Cancer Care 1.



Glossary Terms

anecdotal report
An incomplete description of the medical and treatment history of one or more patients. Anecdotal reports may be published in places other than peer-reviewed, scientific journals.
animal study (AN-ih-mul STUH-dee)
A laboratory experiment using animals to study the development and progression of diseases. Animal studies also test how safe and effective new treatments are before they are tested in people.
bile duct
A tube through which bile passes in and out of the liver.
cancer (KAN-ser)
A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.
Cancer Information Service
CIS. The Cancer Information Service is the National Cancer Institute's link to the public, interpreting and explaining research findings in a clear and understandable manner, and providing personalized responses to specific questions about cancer. Access the CIS by calling 1-800-4-CANCER (1-800-422-6237), or by using the LiveHelp instant-messaging service at https://cissecure.nci.nih.gov/livehelp/welcome.asp. Also called CIS.
case report
A detailed report of the diagnosis, treatment, and follow-up of an individual patient. Case reports also contain some demographic information about the patient (for example, age, gender, ethnic origin).
cell (sel)
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.
chamomile (KA-muh-mile)
A family of plants with daisy-like flowers. Two types are German chamomile and Roman or English chamomile. These are used in teas to calm and relax, to improve sleep, and to help with stomach problems. The essential oil (scented liquid taken from plants) of chamomile is used in perfumes, shampoos, lotions, and aromatherapy.
clinical trial
A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called a clinical study.
coenzyme Q10
A substance found in most tissues in the body, and in many foods. It can also be made in the laboratory. It is used by the body to produce energy for cells, and as an antioxidant. It is being studied in the treatment of cancer and in the relief of side effects caused by some cancer treatments. Also called Q10, CoQ10, vitamin Q10, and ubiquinone.
coffee enema (KAW-fee EH-nuh-muh)
The injection of coffee through the anus into the colon (large intestine). Coffee enemas are being tested in the treatment of pancreatic cancer.
colorectal cancer (KOH-loh-REK-tul KAN-ser)
Cancer that develops in the colon (the longest part of the large intestine) and/or the rectum (the last several inches of the large intestine before the anus).
detoxify (dee-TOX-ih-fy)
To make something less poisonous or harmful. It may refer to the process of removing toxins, poisons, or other harmful substances from the body.
diagnosis (DY-ug-NOH-sis)
The process of identifying a disease, such as cancer, from its signs and symptoms.
diet
The things a person eats and drinks.
digestion (dy-JES-chun)
The process of breaking down food into substances the body can use for energy, tissue growth, and repair.
enema
The injection of a liquid through the anus into the large bowel.
enzyme
A protein that speeds up chemical reactions in the body.
FDA
Food and Drug Administration. An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The FDA also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called Food and Drug Administration.
flaxseed
The seed of the flax plant. It is a rich source of omega-3 fatty acid, fiber, and a compound called lignin. It is being studied in the prevention of prostate cancer. Also called linseed.
follow-up
Monitoring a person's health over time after treatment. This includes keeping track of the health of people who participate in a clinical study or clinical trial for a period of time, both during the study and after the study ends.
Gerson therapy (GER-sun THAYR-uh-pee)
A diet plan that has been claimed to be a treatment for cancer, migraine, tuberculosis, and other diseases. It is a vegetarian diet that includes eating organic fruits and vegetables and 13 glasses of fresh juice each day. It also includes supplements with iodine, vitamin B-12, potassium, thyroid hormone, liver extract, and pancreatic enzymes. No clinical trial to test Gerson therapy has been reported.
immune system (ih-MYOON SIS-tem)
The complex group of organs and cells that defends the body against infections and other diseases.
injection
Use of a syringe and needle to push fluids or drugs into the body; often called a "shot."
iodine (I-oh-dine)
An element that is necessary for the body to make thyroid hormone. It is found in shellfish and iodized salt.
laboratory study
Research done in a laboratory. These studies may use test tubes or animals to find out if a drug, procedure, or treatment is likely to be useful. Laboratory studies take place before any testing is done in humans.
melanoma (MEH-luh-NOH-muh)
A form of cancer that begins in melanocytes (cells that make the pigment melanin). It may begin in a mole (skin melanoma), but can also begin in other pigmented tissues, such as in the eye or in the intestines.
metabolism (meh-TA-boh-lih-zum)
The total of all chemical changes that take place in a cell or an organism. These changes make energy and the materials needed for growth, reproduction, and maintaining health. They also help get rid of toxic substances.
metastatic cancer (meh-tuh-STA-tik KAN-ser)
Cancer that has spread from the place in which it started to other parts of the body.
mineral
A nutrient required to maintain health.
National Cancer Institute
The National Cancer Institute, part of the National Institutes of Health of the United States Department of Health and Human Services, is the Federal Government's principal agency for cancer research. The National Cancer Institute conducts, coordinates, and funds cancer research, training, health information dissemination, and other programs with respect to the cause, diagnosis, prevention, and treatment of cancer. Access the National Cancer Institute Web site at http://www.cancer.gov. Also called NCI.
nutrient (NOO-tree-ent)
A chemical compound (such as protein, fat, carbohydrate, vitamin, or mineral) contained in foods. These compounds are used by the body to function and grow.
nutrition (noo-TRIH-shun)
The taking in and use of food and other nourishing material by the body. Nutrition is a 3-part process. First, food or drink is consumed. Second, the body breaks down the food or drink into nutrients. Third, the nutrients travel through the bloodstream to different parts of the body where they are used as "fuel" and for many other purposes. To give the body proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients.
organ
A part of the body that performs a specific function. For example, the heart is an organ.
organic food (or-GA-nik …)
Food produced without the use of man-made fertilizer, drugs that increase growth, or drugs that kill insects, bacteria, or other living things. In the United States, the Department of Agriculture sets standards for growing, harvesting, processing, and labeling organic foods.
ovarian cancer (oh-VAYR-ee-un KAN-ser)
Cancer that forms in tissues of the ovary (one of a pair of female reproductive glands in which the ova, or eggs, are formed). Most ovarian cancers are either ovarian epithelial carcinomas (cancer that begins in the cells on the surface of the ovary) or malignant germ cell tumors (cancer that begins in egg cells).
pancreas
A glandular organ located in the abdomen. It makes pancreatic juices, which contain enzymes that aid in digestion, and it produces several hormones, including insulin. The pancreas is surrounded by the stomach, intestines, and other organs.
pancreatic enzyme
A protein secreted by the pancreas that aids in the digestion of food.
PDQ
PDQ is an online database developed and maintained by the National Cancer Institute. Designed to make the most current, credible, and accurate cancer information available to health professionals and the public, PDQ contains peer-reviewed summaries on cancer treatment, screening, prevention, genetics, complementary and alternative medicine, and supportive care; a registry of cancer clinical trials from around the world; and directories of physicians, professionals who provide genetics services, and organizations that provide cancer care. Most of this information, and more specific information about PDQ, can be found on the NCI's Web site at http://www.cancer.gov/cancertopics/pdq. Also called Physician Data Query.
potassium (po-TASS-ee-um)
A metallic element that is important in body functions such as regulation of blood pressure and of water content in cells, transmission of nerve impulses, digestion, muscle contraction, and heartbeat.
psychological (SY-koh-LAH-jih-kul)
Having to do with how the mind works and how thoughts and feelings affect behavior.
regimen
A treatment plan that specifies the dosage, the schedule, and the duration of treatment.
retrospective study
A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not. Also called a case-control study.
scientist
A person who has studied science, especially one who is active in a particular field of investigation.
side effect
A problem that occurs when treatment affects healthy tissues or organs. Some common side effects of cancer treatment are fatigue, pain, nausea, vomiting, decreased blood cell counts, hair loss, and mouth sores.
sodium (SOH-dee-um)
A mineral needed by the body to keep body fluids in balance. Sodium is found in table salt and in many processed foods. Too much sodium can cause the body to retain water.
standard therapy (...THAYR-uh-pee)
In medicine, treatment that experts agree is appropriate, accepted, and widely used. Health care providers are obligated to provide patients with standard therapy. Also called standard of care or best practice.
stomach (STUH-muk)
An organ that is part of the digestive system. The stomach helps digest food by mixing it with digestive juices and churning it into a thin liquid.
supplementation
Adding nutrients to the diet.
therapy (THAYR-uh-pee)
Treatment.
tissue (TISH-oo)
A group or layer of cells that work together to perform a specific function.
toxic (TOK-sik)
Having to do with poison or something harmful to the body. Toxic substances usually cause unwanted side effects.
tuberculosis (too-BER-kyoo-LOH-sis)
TB. A disease caused by a specific type of bacteria that spreads from one person to another through the air. Tuberculosis can affect many parts of the body, but most often affects the lungs. A person may not have symptoms of tuberculosis for years, but they may appear when the patient becomes ill with a serious condition like diabetes, AIDS, or cancer. Tuberculosis can usually be treated and cured with antibiotics. Also called TB.
vitamin
A key nutrient that the body needs in small amounts to grow and stay strong. Examples are vitamins A, C, and E.
vitamin A (VY-tuh-min…)
One of several vitamins that the body needs in small amounts to function and stay healthy. Vitamin A is needed for vision, bone growth, reproduction, growth of epithelium (cells that line the internal and external surfaces of the body), and fighting infections. It is fat-soluble (can be stored in the body’s fatty tissue). Foods with vitamin A include fish oils and liver, egg yolks, and whole milk dairy products from animals. It also can be made in the body from a substance found in fruits and vegetables such as cantaloupes, carrots, spinach, and sweet potatoes. Vitamin A is being studied in the prevention and treatment of some types of cancer. Also called retinol.
vitamin B12 (VY-tuh-min ...)
A vitamin that is needed to make red blood cells and DNA (the genetic material in cells) and to keep nerve cells healthy. It is found in eggs, meat, poultry, shellfish, milk, and milk products. Vitamin B12, along with folate, may be given to help reduce side effects in cancer patients being treated with drugs called antimetabolites. Also called cobalamin.
vitamin C (VY-tuh-min…)
A key nutrient that the body needs to fight infection, heal wounds, and keep tissues healthy, including the blood vessels, cartilage, ligaments, tendons, bones, muscle, skin, teeth, and gums. It is an antioxidant that helps prevent tissue damage caused by free radicals. The body does not make or store vitamin C, so it must be taken in every day. It is found in many fruits and vegetables, especially green peppers, citrus, strawberries, tomatoes, broccoli, leafy greens, potatoes, and cantaloupe. Also called ascorbic acid.
x-ray
A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body. In high doses, x-rays are used to treat cancer.


Table of Links

1http://cancer.gov/cancertopics/pdq/supportivecare/nutrition/Patient