• To provide nutrients to the patient according to his physical requirements.
• To provide nutrients to enhance the immunity of the patient.
• To provide sufficient rest to the body particularly to the affected organs, e.g., to give total liquid diet to a diarrhea patient in place of fibrous foods, to provide rest to the liver by not giving fat rich foods to a patient of jaundice.
• To increase or reduce body weight according to the requirement.
• To change the diet of a person according to his capacity of digestion, absorption and metabolism.
• To change the liquidity of foods according to the requirements-liquid, semi- liquid or soft foods.
• To remove the deficiency this may have occurred in the body