Dietitian  A dietitian (or dietician) is an expert in dietetics; that is, human nutrition and the regulation of diet. A dietitian alters their patient's nutrition based upon their medical condition and individual needs. Dietitians are regulated healthcare professionals licensed to assess, diagnose, and treat nutritional problems. A registered dietitian (RD) or registered dietitian nutritionist (RDN) is a dietitian who meets all of a set of special academic and professional requirements, including the completion of a bachelor's degree with an accredited nutrition curriculum, an internship at an approved health-care facility, foodservice organization, or community agency, and satisfactory performance on a registration exam. Roughly half of all RDNs hold graduate degrees and many have certifications in specialized fields such as nutrition support, sports, pediatrics, renal, oncological, food-allergy, or gerontological nutrition. After learning about a patient's health history, favorite foods, eating and exercise habits, the RD helps the person to set goals and to prioritize. Follow-up visits often focus on maintenance and monitoring progress. Most RDs work in the treatment and prevention of disease (administering medical nutrition therapy, as part of medical teams), often in hospitals, health-maintenance organizations, private practices, or other health-care facilities. In addition, many registered dietitians work in community and public-health settings, and/or in academia and research. A growing number of dietitians work in the food industry, journalism, sports nutrition, corporate wellness programs, and other non-traditional dietetics settings. As explained by the American Heritage and Merriam-Webster's dictionaries, the cause of the confusion is that the spelling with "-tian" is an irregular alteration of the ending "-cian", which is otherwise exclusively used to refer to specialists and practitioners of other professions. These and other American dictionaries also list the spelling with "c" but list the spelling with "t" first because this spelling is more common in the United States. Nevertheless, the American publisher McGraw-Hill exclusively uses the spelling with "c" in the 2003 edition of the McGraw-Hill Dictionary of Scientific & Technical Terms and the 2002 edition of the McGraw-Hill "Concise Dictionary of Modern Medicine". The spelling with "t" is the one preferred by the profession itself internationally, but the spelling with "c" is used often enough in texts not written by members of the profession to be considered a valid variant by both American and British dictionaries.