The science of nutrition studies the relationship of foods to optimal health and performance. Proper nutrition means that a person s diet supplies all the essential nutrients to carry out normal tissue growth, repair, and maintenance. The typical diet is high in calories, sugar, fat, saturated fat, and sodium. It is not high enough in fiber.
Nutrition plays a crucial role in the development and progression of chronic diseases.
A diet high in saturated fat and cholesterol increases the risk for atherosclerosis and coronary heart disease. Obesity, diabetes mellitus, and osteoporosis also have been associated with faulty nutrition. The essential nutrients the human body requires are carbohydrates, fat, protein, vitamins, minerals, and water. Vitamins, minerals, and water have no caloric value but still are necessary for a person to function normally and maintain good health. Carbohydrates, fats, proteins, and water are termed macronutrients because proportionately large amounts are needed daily.