Carbohydrates are the sugars, starches, and fibers found in natural products like fruits, grains, vegetables and milk products. Carbohydrates are one of the essential food classes that are critical to a healthy life.
"Carbohydrates are macronutrients, which means they are one of the three primary ways the body gets energy or calories," said Paige Smathers, a Utah-based registered dietitian. The American Diabetes Association notes that carbohydrates are the body's main source of energy. They are called carbohydrates because, at the chemical level, they contain carbon, hydrogen and oxygen.
Function of carbohydrates
Carbohydrates are classified basic or complex. The
difference between the two forms is the chemical structure and how quickly the
sugar is absorbed and digested. Generally speaking, simple carbohydrates are
digested and absorbed more quickly and easily than complex carbohydrates.
Simple carbohydrates contain just one or two sugars, such as fructose (found in fruits) and galactose (found in milk products). These single sugars are called monosaccharides. Carbohydrates with two sugars; such as sucrose (table sugar), lactose (from dairy) and maltose (found in beer and some vegetables); are called disaccharides.
Complex carbohydrates (polysaccharides) have three or more sugars. They are often referred to as starchy foods and include beans, peas, lentils, peanuts, potatoes, corn, parsnips, whole-grain bread and cereals.
Smathers pointed out that, while all carbohydrates function
as relatively quick energy sources, simple carbohydrates cause bursts of energy
much more quickly than complex carbohydrates because of the quicker rate at
which they are digested and absorbed. Simple carbohydrates can lead to spikes
in blood sugar levels while complex carbohydrates provide more sustained
energy.