Registered dietitians are the healthcare professionals most trained, experienced and qualified to help people make healthy food choices. To become a registered dietitian, you have to undergo rigorous training in the biological, chemical and physical sciences, math, business management, education, psychology, food, and culture. That's the short list. You will also have to take a series of courses in food composition, food preparation, human nutrition and related subjects. Most registered dietitians work in hospitals, but the field of opportunities is wide open. To become a public health nutritionist, a master’s degree in public health or nutrition is generally required. Public health nutritionists work in clinics with patients who have diseases, including diabetes, heart disease, high blood pressure, high cholesterol and other chronic diseases. More and more dietitians are choosing to become entrepreneurs, setting up their own practice in whatever area of emphasis they have a passion for. Others are creating and working for nonprofit organizations. These organizations serve children in Head Start, after school programs, parent organizations and other groups. Consulting for major food and pharmaceutical corporations, college teaching are yet other areas where you might work as a registered dietitian. Next: Compensation and other things you should know about being a registered dietitian