These days any one can claim themselves as a nutritionist just by studying some books and magazines. Credentials are very important when finding your Nutritionist.
An authentic nutritionist should have completed his course in the university accredited by the American Clinical Board of Nutrition. Before you visit a nutritionist you can research and find out how long have they been in this profession, where did they get the degree from and any other education related information.
You can easily get this information from the Nutritionist directly. Be sure to make thorough background verification. You can also verify with the local Chamber of Commerce to ensure if the Nutritionist has any complaints over past years.
You can visit or call the institution the person claims to have done his course. To find more about the reputation of his institution and degree you can visit a local library or make a search online for the directory of colleges and universities called Accredited Institutions of Post Secondary Education.
Another way is to check if the nutritionist has done any specialization known as registered dietitian which is given to a person who successfully completes on the job training coursework of American Diet Association .