Four Functions of Carbohydrates in Our Bodies

Carbohydrates have been the center of controversy for many years. Fad diets appear constantly, warning about the dangers of carbs and encouraging you to limit how many you eat. Yet carbohydrates play a critical role in your health and well-being. According to the 2010 Dietary Guidelines for Americans, between 45 and 55 percent of your calories should come from carbohydrates, including whole grains, fruits, vegetables and low-fat dairy foods.

Carbohydrates are necessary for a healthy body. (Image: outline205/iStock/Getty Images)

Provide Energy

Carbohydrates are the the preferred fuel source of your body. When you eat foods that contain carbohydrate, your body breaks them down into glucose. Glucose provides fuel for each cell in your body, particularly your brain and nerve cells. Your body can break down carbohydrates for energy much more efficiently than protein or fat. If your body doesn't need glucose immediately, it will store energy in the form of glycogen to be used later.

Spare Protein

If you don't eat enough carbohydrates, your body will use protein as an energy source. Protein is needed to build muscle as well as several other functions, but if it is used for energy due to lack of carbohydrates, it cannot perform its proper function. Because your body is less efficient at breaking down protein to use for fuel, dangerous byproducts are released making it difficult on your kidneys as they try to rid the body of these toxins.

Maintain Digestive Health

Fiber is a type of carbohydrate that is necessary for digestive health. Some fiber is digestible and some is not. Both types of fiber are necessary to help food move through your intestinal tract and ultimately out through the colon, taking waste products with it. Fiber helps prevent constipation and diarrhea. Fiber also helps you feel full longer, which helps you avoid overeating.

Stimulate Growth of Good Bacteria

Carbohydrates ferment in your intestines which stimulate the growth of bacteria. This bacteria helps break down food so it can be used by the body. Some bacteria protect the colon from harmful cells such as cancer. The foods that stimulate this type of bacteria are known as prebiotics.