carbohydrate
Meaning of carbohydrate: Carbohydrates are energy-supplying molecules built from carbon, hydrogen, and oxygen, ranging from simple sugars to complex starches, fiber, and structural compounds.
Definition of carbohydrate
A carbohydrate is a type of molecule made up of carbon, hydrogen, and oxygen, generally in a ratio that gives the group its name. Carbohydrates make up one of the three major classes of nutrients, alongside protein and fat, and serve as a primary source of energy for the body.
Simple carbohydrates include single sugars such as glucose and fructose and small combinations of them such as sucrose, while complex carbohydrates are long chains of these sugar units linked together, including starch, which the body breaks down for energy, and cellulose, a structural carbohydrate that forms plant cell walls.
Beyond nutrition, carbohydrates serve other biological roles, forming part of the backbone of DNA and RNA, contributing to the structural material of fungal cell walls in the form of chitin, and attaching to proteins on the surface of cells, where they help cells recognize and interact with one another.
Used in a sentence
Dietary counseling addressed the appropriate balance of carbohydrate, protein, and fat in the patient's meal plan.
Good to know
Carbohydrate is a broad chemical category rather than a single substance, so foods described as carbohydrates can differ considerably in how quickly they are digested and how they affect blood sugar.
Word origin
Where “carbohydrate” comes from
Formed from carbo-, referring to carbon, and hydrate, from Greek hydor, meaning water, reflecting the historical observation that these molecules contain hydrogen and oxygen in the same ratio found in water.