Nutritionists and dietitians are professionals, equipped with the knowledge of the chemistry and nutritional value of foods and their preparation. They are the experts who develop new uses of food, advise patients in a clinic regarding their diet, serve as consultants to public health teams, supervise the serving of food in industrial cafeterias or hospitals, assist individuals or groups in dietary education, and teaching nursing schools, colleges and universities.

Major Tasks Performed
There is an essential difference in the function of the nutritionist and of the dietician. The nutritionist studies the effect of a viety of food on an individual in terms of metabolism and long terms physical results. Nutritionists work with both normal people as well as referrals from medical practitioners.
Their work has two aspects:
Prevention of illness in those whose physical characteristics tend towards it, like those suffering from obesity, malnutrition or hereditary disorders.

Rehabilitation after illness or surgery, which includes helping patients to cope with their new life, and showing them how to maximize the benefits of the treatment.

The dietician, on the other hand, provides guidance on the development of healthy eating habits, for example, with overweight persons–advising on how to modify food consumption patterns, what high nutrition supplements to include in the diet and drawing up a personalised food plan to ensure that individual dietary requirements are met.

Other important tasks undertaken by the dietician are:
Meal Planning, that is,deciding what foods should be eaten, and in what quantities.
Administration, which involves looking into the day–to–day functioning of an organisation’s dining facilities.

Both nutritionists and dieticians spend much of their time in counselling. They also specialise in one or more of these areas:

Institutional Food
Administration deals with food administration in institutions such as hotels, hospitals, colleges, industrial plants, armed forces and so on. The major activities in this area are the estimation and purchase of food supplies and equipment; receiving, checking and taking inventories of provisions; supervision of the chef and other kitchen hands to ensure that food is properly cooked and served; and menu planning, which is one of the most essential tasks in this area.

Therapeutic Nutrition is applied mainly in hospitals or private clinics. Therapeutic dieticians work in conjunction with medical practitioners, while drawing up special menus for patients suffering from ailments like diabetes, ulcers, heart disease, tuberculosis etc. where dietary restrictions are necessary for treatment. Menu components are discussed with both physician and patient, to explain the purpose of the diet, discover food preferences and prepare the patient for continuing the diet at home. Thus therapeutic dieticians are responsible for the preparation of a daily meal pattern that combines the patient’s food habits with remedial needs. They also keep records of patients–responses to new diets.

Clinical Dietetics differs slightly from therapeutic nutrition, in that it concerns patients who are not hospitalised, but are referred to the clinic by a physician. They include expectant mothers, and people suffering from obesity or other nutritional problems , who are taught to understand and use diet effectively.

Public Health Nutrition involves working with para–medics in rural and semi–urban areas for giving advice and guidance to expectant mothers, for pre–natal and post–natal care with regard to diet and hygiene.

Community Nutrition is part of the Government Health Scheme which handles the nutritional needs and short coming of the are concerned.

Food Technology is widely applied in the food industry, where nutritionists are employed at various levels in the development, manufacture and making of food products.