Hello Janeth: Great question and good that you've discovered your interest area. Dietician is considered a biomedical science as well as a health science. As such several science courses are required. TAken from the Emory University Dietian studies website. This field of study is also a graduate program which means that you will need to graduate from an undergraduate program with a high G.P.A. and certain specific classes listed on your college of choice's website. I provide an example here from Emory University: http://nutrition.emory.edu/academics/curriculum.html (copy and paste to address bar to view). It appears that testing for certification and completion are also required as well as electives and internships or handson work before graduation to gain insight into various areas in which to work. I hope this helps!