Dietetics: The application of nutritional principles to regulation of the diet and feeding persons or groups of persons.Nutrition Therapy: Improving health status of an individual by adjusting the quantities, qualities, and methods of nutrient intake.Nutritional Physiological Phenomena: The processes and properties of living organisms by which they take in and balance the use of nutritive materials for energy, heat production, or building material for the growth, maintenance, or repair of tissues and the nutritive properties of FOOD.