You'll definitely become famous among your clients for restricting their diets or helping them lose weight—and some of those clients might even be famous. Not all dietitians work in hospitals or medical clinics. Some of them work in the sports world—in athletic departments in colleges, or for soccer teams, football teams, or other pro clubs.
You can also become a celebrity, though the chances of that happening aren't exactly good. Lisa de Fazio transformed her career when she became an infomercial spokesperson, a host for television shows, and produced lifestyle videos for Perez Hilton. When television shows look for a glamorous dietitian, they call on her.
How did she achieve her fame? She branded herself as a fashionable and personable dietitian who knows her way around a kitchen. If you work with famous patients, host your own show, write a book or two, and market yourself well, you too can perhaps be a famous dietitian.