Simple carbohydrates are dietary components made up of one or two sugar molecules. The most basic is glucose, the type of sugar our bodies and brains use for fuel every day. Glucose is a monosaccharide, which means "single sugar." Other monosaccharides include fructose, which is found in fruits and vegetables, and galactose, which is found in milk.
The single sugars can be combined to form disaccharides, a term that means "two sugars." These sugars include:
- Lactose (milk sugar) is made up of glucose and galactose molecules. People who are "lactose intolerant" can't digest this sugar properly.
- Sucrose (table sugar) is composed of glucose and fructose molecules. This is the white powdery or granular substance we typically refer to as "sugar" when we are cooking or baking.
- Maltose (malt sugar) is produced during the malting of cereals such as barley.
Digesting Simple Carbohydrates
Simple sugars are easy to digest. When you eat them, your body breaks them apart and they're absorbed into your blood stream through the small intestine. Any sugar your body doesn't use for fuel is converted to fat and stored in adipose tissue.
Identifying Simple Carbohydrates
Processed foods that contain simple carbohydrates are usually high in calories, and not very nutritious, so you may wish to cut back on foods that contain these ingredients:
- Brown Sugar
- Raw Sugar
- High Fructose Corn Syrup
- Corn Syrup
- Malt Sugar
Fruits and vegetables naturally contain fructose; however, they're also good for you because they're nutrient-dense and they contain fiber that slows down the digestion and absorption of sugar. Fruit juices that don't contain fiber can still be very nutritious, but without the bulk of whole fruit, the simple carbohydrates are absorbed much more quickly. Generally, it's better to eat whole fruit rather than drink fruit juice.
Milk contains lactose, which is a problem for people who are lactose-intolerant. People with this condition must avoid milk and many other dairy products or use supplemental enzymes called lactase that help them digest milk sugar.
Source: Centers for Disease Control and Prevention. "Nutrition for Everyone: Basics: Carbohydrates." Accessed January 5, 2010. http://www.cdc.gov/nutrition/everyone/basics/carbs.html.