Derived mostly from plants, carbohydrates are essential nutrients that give us fuel to live. Carbs are found in a wide variety of foods....from refined sugar, known as simple carbs, to nutritious whole grains, vegetables, fruits, and legumes, known as complex carbs.

Unfortunately, carbohydrates have been maligned over the last decade because they are believed to elevate blood sugar levels, which can contribute to increasing the risk of diabetes and obesity.

That is not true of all carbs, though. Here's why:
Carbs are broken down by the body into sugar, which is converted to glucose. But not all carbohydrates are converted into glucose at the same rate. Some are digested more slowly or more rapidly than others. This measurement of how fast or how slowly food is converted to sugar in the bloodstream is called the glycemic index.

Nutrition experts say foods with a highly glycemic index, such as refined grains, as in commercially baked cookies and cakes, are converted rapidly to glucose, causing a sharp rise in blood sugar; one of the reasons for this is that highly processed foods lack fiber.

Foods with a low glycemic index, such as fiber-rich whole grains, fruits, vegetables, and legumes, are digested more slowly. They regulate blood sugar, give a feeling of fullness and provide energy for a longer stretch.