No. There is no evidence that a ketogenic diet can cure cancer. Some studies suggest a ketogenic diet may alleviate treatment symptoms associated with specific cancer types such as brain tumors.
Yet other studies suggest ketones, the fuel the body uses on a keto diet, can promote the growth and spread of specific tumor types. Clearly, the potential benefits and harms of a ketogenic will depend on many factors including cancer type and other health issues.
No studies show a ketogenic diet is superior to a typical healthy diet for improving outcomes or survival in cancer patients.
Currently, ClinicalTrials.gov lists around two dozen clinical trials on the ketogenic diet and cancer, so oncologists and dietitians should be able to answer the questions regarding which cancer patients may benefit from the diet and who should avoid it.