If you have a question about nutrition, the most convenient source of information may be your physician, a local dietitian or home economist, or a local college or university nutrition department.
If your doctor is interested in nutrition, he or she may be a good place to start. The principles of nutrition are those of human biochemistry and physiology, courses required in every medical school. Although many medical schools do not teach a separate required course in nutrition, this does not mean that the subject is ignored. Many medical educators prefer that nutrition be included in other courses at the point where it is most relevant. In addition, most medical schools offer an elective course in nutrition.
Medical training, of course, does not end on graduation day. The medical profession advocates lifelong education, and physicians can further their knowledge of nutrition by reading medical journals, discussing cases with colleagues, and attending courses. If your doctor is unable or unwilling to provide what you need, you can be referred to someone who will—usually a registered dietitian.
Many accredited universities offer nutrition courses based on scientific principles and taught by qualified instructors. A bachelor’s degree in nutrition requires four years of full-time study that qualify a graduate for entry level positions in dietetics or food service, often in a hospital. A master’s degree, which can widen career opportunities, requires two more years of full-time study beyond the undergraduate level. People who wish to become nutrition researchers usually pursue a doctorate (Ph.D.) in biochemistry, which requires at least two years of additional study plus a thesis based on original laboratory research. Those wishing to concentrate on teaching or educational research usually seek a Ph.D. or Ed.D. degree in nutrition education.
Regular membership in the American Society for Nutrition—formerly called the American Institute of Nutrition and the American Society for Nutritional Sciences—is open to open to any individuals with a doctoral-level degree (Ph.D., M.D., D.D.S, D.V.M., D.Pharm, etc.) in nutrition or a related field from an accredited institution with notable accomplishments as an author of a nutrition publication in a peer-reviewed journal.
Nutritionists at the doctoral level may also seek certification. From 1984 through 2001, certification was offered by by the American Board of Nutrition to specialists in clinical nutrition (M.D.’s only) or human nutritional sciences (M.D.’s and Ph.D.’s). Since 2001, physician certification has been available from the American Board of Physician Nutrition Specialists (ABPNS), Board certification requires passage of comprehensive examination. Most board-certified nutritionists are affiliated with medical schools and hospitals, where they conduct clinical research and offer consultation to primary-care physicians.
Registered dietitians (R.D.s) are specially trained to translate nutrition research into healthful, tasty diets. The R.D. credential is available to individuals who obtain a bachelor’s degree in nutrition accredited by the Academy of Nutrition and Dietetics (AND) (formerly called the American Dietetic Association), complete an approved dietetic internship, and pass a comprehensive written test covering all aspects of nutrition and food-service management. To maintain their credential, they must also participate regularly in approved continuing education programs. Although completion of a masters degree or Ph.D is highly desirable for nutrition professionals, it is not required to become a registered dietitian. Most active R.D.s work in hospitals. Typically, they counsel patients and conduct classes for pregnant women, heart and kidney patients, diabetics, and other persons with special dietary needs. Dietitians are also employed by community agencies such as geriatric, day- care, and drug/alcohol abuse centers. Some dietitians do research. Others engage in private practice where they counsel physician-referred clients. The AND also has a certification process for advanced-level practitioners and for specialists in renal (kidney), pediatric, and metabolic nutrition. Unfortunately, many members of the academy’s Dietitians in Integrative and Functional Medicine (DIFM) Practice Group are not only offering services that are highly questionable but also appear to be outside the legitimate scope of dietetic practice.
The Certification Board for Nutritional Specialists (CNNS) was founded by the American College of Nutrition (ACN) in 1993. It originally offered a Certified Nutrition Specialist (CNS) credential only to professionals with an accredited master’s or doctoral degree who have clinical experience and pass an examination. In 2009, it severed its connection with ACN and became an independent nonprofit organization. In 2010, it opened its certification process to people with a degree in medicine, dentistry, chiropractic, naturopathy, and several other health disciplines. CBNS’s certification requirements remain substantial but less than those of the American Board of Physician Nutrition Specialists.. In addition, it is not clear how rigorously they investigate their applicants. Many CNS holders have distinguished nutrition credentials. However, I know of at least two people who became certified even though their “Ph.D” degrees came from a nonaccredited correspondence school.
Most conditions for which detailed nutrition advice is needed require medical diagnosis first. These include high blood cholesterol, diabetes, severe food allergy or sensitivity, high blood pressure, certain digestive problems, osteoporosis, severe kidney disease, cancer, and obesity. Consultation with an expert can also be worthwhile for pregnant and lactating women, competitive athletes, and individuals who feel confused about nutrition.
A Certified Clinical Nutritionist (CCN) credential is offered by the Clinical Nutrition Certification Board (CNCB), an organization founded in 1991 to provide credentialing to nutrition professionals who might not be eligible to become registered dietitians or to be certified by the American Board of Nutrition. Although some members are qualified and practice appropriately, both CNCB and its sponsoring organization (the International and American Associations of Clinical Nutrition) include promoters of highly dubious practices among their leaders and members. Although some members are qualified and practice appropriately, CNCB’s required clinical nutrition course promotes the use of homeopathy, dubious laboratory tests, detoxification, herbology, homeopathy, and alternative cancer therapies and several its recommended reference books advocate highly dubious practices.
American Health Science University offers a Certified Nutritionist (CN) credential to students who complete its six-course “distance learning program” and take an examination. Although accredited, it is closely aligned with the health-food industry and should not be regarded as trustworthy. Its president, James R. Johnston, does not appear to have a accredited doctoral degree.
The American Association of Nutritional Consultants issues a Certified Nutritional Consultant (CNC) credential to persons who take an open-book test. The CNC credential should be regarded as bogus.
The Society of Certified Nutritionists (SCN), established in 1985, includes Certified Clinical Nutritionists (CCN), Certified Nutritionists (CN), and Certified Nutrition Consultants (CNC) among its members. SCN membership should be regarded as a sign of poor judgment.
Beware of Unqualified Individuals
Because the titles “nutritionist” and “nutrition consultant” are unregulated in most states, they have been adopted by many individuals who lack recognized credentials and are unqualified. In addition, a small percentage of licensed practitioners are engaged in unscientific nutrition practices. The best way to avoid bad nutrition advice is to identify and avoid those who give it. I recommend steering clear of:
- Anyone who says that everyone needs vitamin supplements to be sure they get enough. Most people can get all the vitamins they need by eating sensibly.
- Anyone who suggests that most diseases are caused by faulty nutrition. Although some diseases are diet-related, most are not.
- Anyone who suggests that large doses of vitamins are effective against a large number of diseases and conditions. That is simply untrue.
- Anyone who suggests hair analysis as a basis for determining the body’s nutritional state or for recommending vitamins and minerals. Hair analysis is not reliable for this purpose.
- Anyone who claims that a wide variety of symptoms and diseases are caused by “hidden food allergies”
- Anyone who uses a computer-scored “nutrient deficiency test” as the basis for prescribing vitamins. There are valid ways that computers can be used for dietary analysis. But those used for recommending vitamins are programmed to recommend them for everyone.
- All practitioners—licensed or not—who sells vitamins in their offices. Scientific nutritionists do not sell vitamins. Unscientific practitioners often do—usually at a considerable profit.
This article was revised on October 14, 2012.