Nutrition

Nutrition is the process by which the body obtains and uses nutrients from food and beverages to support growth, development, maintenance, and normal physiological function. The term also refers to the scientific study of these processes and of how food and nutrients relate to human physiology, health, and disease .^1,2

Nutrition involves more than consuming food. Food components may undergo digestion before nutrients are absorbed through the gastrointestinal tract and transported within the body. Once absorbed, nutrients can be metabolized, used to provide energy or build and maintain tissues, or stored for later use. These processes help determine how substances consumed in food become available to and are used by the body .^2,3

Nutrients have different physiological roles. Carbohydrates, fats, and proteins are commonly classified as macronutrients, while vitamins and minerals are classified as micronutrients. Macronutrients are generally required in relatively large amounts and can provide energy or material for biological processes, whereas micronutrients are required in smaller amounts and support numerous physiological functions without themselves serving as energy sources .¹

Nutrition should be distinguished from diet. Diet describes the foods and beverages a person consumes, whereas nutrition encompasses the body's processing and use of nutrients as well as the scientific study of these processes. Diet is therefore an important part of nutrition, but the two terms are not synonymous .^1,2