Nutrition Part II: Carbohydrates

Author: Joseph Krachenfels

Carbohydrates are composed of carbon, hydrogen, and oxygen, and “constitute the main source of energy for all body functions, particularly brain functions, and are necessary for the metabolism of other nutrients” (Mosby’s 260). Carbohydrates “are the easiest form of food for the body to convert into energy, and once ingested carbohydrates are turned into glucose, which circulates in the bloodstream being readily available, and into glycogen which is stored in the liver and muscle cells, for later use” (Schwarzenegger 672).

Carbohydrates are chiefly divided into 3 different chemical classes, Monosaccharides, Disaccharides, and Polysaccharides. Monosaccharides are single sugars, otherwise referred to as simple carbohydrates. Disaccharides are double sugars, and are also referred to as simple carbohydrates. Polysaccharides are multiple sugars, otherwise referred to as complex carbohydrates. Simple carbohydrates (Monosaccharides, and Disaccharides) like those found in fruits and processed sugars break down very rapidly in the body, making them a good source of quick energy. Complex carbohydrates (Polysaccharides) like those found in rice, potatoes, and pasta, take longer to break down in the body, and provide a more even distribution of energy over a longer period of time.

The chart below lists the 3 different chemical classes (Monosaccharides, Disaccharides, and Polysaccharides) their respective class members, and food sources.

Chemical Class Class Members Food Source
Monosaccharides (simple carbohydrates) Glucose (blood sugar) Corn syrup, many processed foods
  Fructose (fruit sugar) Fruits, honey
  Galactose (milk sugar) Lactose (milk)
Disaccharides (simple carbohydrates) Sucrose (table sugar) Sugar, sugar cane, molasses
  Lactose (milk sugar) Milk
  Maltose (malt sugar) Sweetener
Polysaccharides (complex carbohydrates) Starch and cellulose (plant) Grains and cereal products, cereal, bread, crackers, baked goods, pasta, rice, corn, legumes, potatoes, other vegetables
  Glycogen (animal) Liver, and muscle meats
  Dietary fiber Whole grains, fruits, vegetables, nuts, seeds, skins

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Arnold Schwarzenegger Encyclopedia of Modern Body Building, Simon & Schuster, 1985.

Mosby’s Medical, Nursing, & Allied Health Dictionary, Mosby, 1998.