Max Gerson (October 18, 1881 – March 8, 1959) was a German-born American physician who developed the Gerson Therapy, a dietary-based alternative cancer treatment that he claimed could cure cancer and most chronic, degenerative diseases. Gerson described his approach in the book A Cancer Therapy: Results of 50 Cases (1958). The National Cancer Institute evaluated Gerson's claims and concluded that his data showed no benefit from his treatment.

From Sloan Kettering website:

The Gerson regimen was developed by Max Gerson 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 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.