Carbohydrates are one of the three main macronutrients, along with proteins and fats, and they are a primary source of energy for the body. Chemically, carbohydrates are molecules made up of carbon, hydrogen, and oxygen atoms, with a basic structure of carbon atoms bonded to water molecules. Carbohydrates can be categorized into three main types based on their chemical structure and how the body digests and utilizes them:
Simple Carbohydrates: Also known as sugars, simple carbohydrates are composed of one or two sugar molecules. They are quickly digested and absorbed by the body, leading to rapid increases in blood sugar levels. Sources of simple carbohydrates include:
- Monosaccharides: Single sugar molecules such as glucose (found in fruits and honey), fructose (found in fruits and vegetables), and galactose (found in dairy products).
- Disaccharides: Two sugar molecules linked together, including sucrose (table sugar), lactose (found in dairy products), and maltose (found in grains and beer).
Complex Carbohydrates: Complex carbohydrates are composed of long chains of sugar molecules, which take longer for the body to break down and digest. They provide a more sustained release of energy and help maintain stable blood sugar levels. Sources of complex carbohydrates include:
- Starch: Found in grains (such as wheat, rice, oats, and barley), legumes (such as beans, lentils, and peas), and starchy vegetables (such as potatoes and corn).
- Dietary Fiber: Found in fruits, vegetables, whole grains, legumes, nuts, and seeds, dietary fiber is a type of complex carbohydrate that cannot be fully digested by the body. It provides various health benefits, including promoting digestive health, supporting weight management, and reducing the risk of chronic diseases such as heart disease and type 2 diabetes.
Non-Digestible Carbohydrates: These are carbohydrates that cannot be broken down by human digestive enzymes and thus pass through the digestive system without being absorbed. Non-digestible carbohydrates, such as resistant starches and certain types of fiber (e.g., insoluble fiber), can still provide benefits to gut health by serving as food for beneficial gut bacteria.