In addition to an academic degree, most legitimate nutritionists seek professional certification. Board certification requires passage of comprehensive examination. To qualify, they must have appropriate professional experience and pass a comprehensive written test covering all aspects of nutrition and food-service management. 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.
Some dietitians do research.
Others engage in private practice where they counsel physician-referred clients. The Certification Board for Nutritional Specialists was founded by the American College of Nutrition in 1993. Its requirements are substantial but less than those of the American Board of Nutrition. 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.