A dietitian (sometimes spelled dietician) is an expert in food and nutrition.
Dietitians help promote good health through proper eating. They may also supervise the preparation and service of food in hospitals, develop modified diets, participate in research, and educate individuals and groups on good nutritional habits. The goals of the dietitian is to provide advice on how to obtain, prepare, and serve flavorsome, attractive and nutritious food to patients, family members and health care providers.
In Australia nutrition professionals are degree qualifed professionals who need to be accredited with the Dietitians Association of Australia. Dietitians registered with the Association are only able to use the label "Accredited Dietitian" when they have met strict, specific educational and experiential prerequisites and passed a national registration examination.
Some Dietitians call themselves nutritionists. However, some people who may call themselves a nutritionist are not necessarily accredited or registered dietitians. Different professional terms are used in other countries.

read more - DAA website

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