The giant molecules are packed side by side in a plant root or seed, providing energy for the plant. All starches are plant materials. Cereal grains, such as wheat, rice and corn, are rich sources of starch, constituting a large part of the world's food supply, generally in the form of breads and pastas. Starches are also found in potatoes and legumes. Starchy foods, once avoided by dieters as fattening, are actually a good source of energy for those who want to lose weight.
Many people think that starchy foods such as bread, potatoes and pasta are high in calories.
They aren't - until the bread is thickly buttered, the potatoes generously topped with sour cream, and the macaroni mixed with cream and cheese sauce. Without the toppings, or with only moderate amounts, complex carbohydrate foods can be less fattening than animal-protein foods that naturally contain fat. What's more, a diet high in carbohydrates just may be more slimming than a diet of comparable calories that is high in fat. The researchers also found that when the participants switched to a diet high in complex carbohydrates, they became full more quickly and unconsciously decreased their caloric intake. And like starches, dietary fiber is found abundantly in plants, especially in the outer layers of cereal grains and the fibrous parts of fruits, legumes, and other vegetables.