Complex carbohydrates, or polysaccharides, contain fiber and, unlike simple carbs, provide a steady flow of energy over a sustained period of time. In addition, they allow you to feel fuller and are more nutrient rich. Grains, starchy vegetables and fibrous vegetables are all complex carbohydrates. Starchy carbs come from such plant sources as potatoes, cereals, bread, rice and pasta. The fiber found in complex carbs acts as your body's natural cleanser, and protects against gastrointestinal disease and colon cancer. Fibrous carbs are also a great fat loss aid.

The glycemic index (GI) is a scale from 1 to 100 that measures how carb foods affect blood sugar. High GI foods, such as potatoes, break down into blood glucose quickly. These are classified as high GI foods. There is a belief that high GI foods are more fattening than low GI options. This has, however, been disproven. Eating low GI foods does not lead to fat loss.

The key health difference between types of carbs comes down to whether the food is natural or refined. If it came out of the ground or off a tree or from a plant, then you can rest assured that it's a worthwhile energy source. The more touched by humans, however, the less beneficial a carb will be. Worst of the worst are refined sugar products. Reducing your intake of refined sugar will see immediate overall health benefits.