Differences Between Simple Sugars & Starches

Sucrose. Fructose. Dextrose. Sorbitol. Seeing these items on a product's nutrition list is enough to make your head spin. What are they, and what do they mean? They are all types of dietary sugars, and a better understanding of the differences between them will help to dispel confusion when you are trying to decode food labels.

Basic Facts

• All sugars are classified as "carbohydrates," but the complexity of their forms will determine their type and the nutritional role they play. Simple sugars are singular in their molecular structure and therefore metabolize quickly for instant-release fuel. The chemical strands of complex sugars contain a combination of sugar types, which form longer chains that are more resistant to breakdown in the digestive process.

Simple Sugars

• A sugarbowl at the table

  Fructose is comprised of a single carbohydrate unit, the most basic of sugar molecules, and is commonly called "fruit sugar."

  Glucose, like fructose, is comprised of a single carbohydrate unit, and is commonly called "grape sugar."

  Dextrose is another name for glucose.

  Sucrose, commonly called table sugar, is actually a "double sugar": two simple sugars stuck together. Sucrose is made up of a glucose joined to a fructose.

  Galactose and xylose are simple sugars found in sources other than fruits or vegetables, and may be added to foods by food processors.

Starches (also known as Complex Sugars)

• Rice is a source of starch.

  Pure starch is composed of amylose and amylopectin, complex sugars found in the seeds and roots of plants. Together known as "amylum," they are the most important carbohydrate in the human diet and are contained in such staple foods as potatoes, wheat, corn and rice.