- Carbohydrates are a class of nutrients that is a major source of energy for the body - Can also server as a glue that holds cells togehter - Classified as simple or complex - Plants are rich sources of carbohydrates There are 3 categories of carbs. # Sugars - A **monosaccharide** is a simple sugar that is the basic molecule of carbohydrates: - Glucose: Primary fuel for muscles, nerves, and other cells, the most common. - Fructose: In **fruits**, honey, and certain vegetables - Galactose: Component of lactose - A **disaccharide** is a simple sugar comprised of two monosaccharides. - Maltose: Disaccharide composed of two glucose molecules "malt sugar" - Sucrose: Disaccharide composed of a glucose and fructose molecule "table sugar" - Lactose: Disaccharide composed of a glucose and a galactose molecule "milk sugar" - High fructose corn syrup is a syrup obtained from the processing of corn - No conclusive evidence that the use of HFCS causes poor health and disease - Excessive calories from beverages sweetened with HFCS contributes to increased risk for diabetes and heart disease - Nutritive sweeteners are substances that sweeten and contribute energy to foods - Each gram of mono or disaccharide supplies 4 kcal - Added sugars are sugars added to foods during processing or prep - The main source of added sugars in the American diet is sugar sweetened beverages. - Alternative sweeteners are substances that sweeten foods while providing few or no calories - Sugar alcohols are alternative sweeteners use to replace sucrose in some some sugar free foods: - Sorbitol, xylitol, mannitol - Not fully absorbed by the intestinal tract - Supply 2kcal/g - Can cause diarrhea when consumed - Non-nutritive sweeteners are a group of synthetic compounds that are intensely sweet tasting compared to sugar - Examples include Aspertame, Saccharin, Acesulfame-K, Neotame, and Sucralose - Glycogen = storage form of glucose - A highly branched storage polysaccharide in animals - Muscles and liver are major storage sites # Starches Complex carbs have 3 or more monosaccharides bonded together - Starch is a storage polysaccharide in plants. - Composed of amylose and amylopectin - Rich sources include: - Bread and cereal products made from wheat, rice, barley, and oats # Fiber - Plants also use complex carbohydrates to make supportive and protective structures - Dietary fiber is non-digestible plant material - Most types are polysaccharides - Soluble fiber - Forms of dietary fiber that dissolve or swell in water. includes pectins, gums, mucilages, and some hemicelluloses - Insoluble fiber - Forms of dietary fiber that generally do not dissolve in water: Includes cellulose, hemicelluloses, and lignin