Common myths about nutrition education and care of cancer patients are debunked and realities are discussed. First, frequently held misconceptions of nonspecialized health professionals are considered. These include the myths that (1) diet change in the population will be rapid now that dietary guidelines to prevent cancer have been issued; (2) nutrition education is best relegated to the dietitian for cancer patients; (3) patients do not need nutritional advice until treatment is actually in progress, and then only rarely while they are hospitalized; (4) nutrition education needs taper off once consolidation or intermittent therapy begins and cease entirely with survival of 5 or more years; and (6) nutrition education of the family usually can be ignored. Next, common myths which many patients and their families subscribe to are discussed. These myths include the following: (1) by following the cancer prevention dietary guidelines, protection against cancer is guaranteed; (2) if only the victim had eaten differently, the cancer never would have developed; (3) cancer prevention dietary guidelines also should be followed in the nutritional support of cancer patients; (4) cancer patients can rely on their appetites and hidden hungers to stay in good nutritional balance; (5) special diets can cure cancer; (6) all cancer anorexia can now be reversed by following proper diet; (7) children who have cancer should neither be fed nor can they eat diets similar to those fed to other children at that age; (8) special nutritional support measures such as tube feeding and total parenteral nutrition are only useful for those younger than 65 years; and (9) there is no sense in paying attention to the nutrition of cancer patients in hospices because they are going to die anyway. It is concluded that nutrition education can enhance quality of lie, for the patient and his family, throughout his illness and after his recovery.