Complex Carbohydrates

Complex carbohydrates: Why do we need them, and are they good for us? A governmental take on complex carbohydrates and why we eat them.

Complex Carbohydrates -- A Brief Report

What Are Complex Carbohydrates?

U.S. Surgeon General C. Everett Koop in his 1988 Report on Nutrition and Health recommended reduction in four areas (fats and cholesterol, weight, sodium and alcohol). Only one area received a positive recommendation from the Surgeon General - "complex carbohydrates and fiber." The report says: "Increase consumption of whole grain foods and cereal products, vegetables (including dried beans and peas), and fruits."

According to John Vanderveen, director of the division of nutrition at FDA's Center for Food Safety and Applied Nutrition, complex carbohydrates should make up about 55 percent of the calories in our daily diet, with fat making up 30 percent or less and protein the remainder. In an 1,800-calorie daily diet, that 55 percent represents about 250 grams of complex carbohydrates - nearly 1,000 calories.

Complex carbohydrates, or polysaccharides, are made mostly of long strands of simple sugars. They are found in grains, fruits, legumes (peas and beans), and other vegetables. Complex carbohydrates include three types of dietary fiber - cellulose, hemicellulose and gums - and starches.

A single starch molecule may contain from 300 to 1,000 or more sugar units. 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. Starches (and proteins) provide only four calories per gram, while fat provides nine calories per gram. 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. Studies still are preliminary, but a research report published in the January 1989 American Journal of Clinical Nutrition suggested that "altering the composition of the diet in favor of a higher carbohydrate-to-fat ratio may decrease the incidence of obesity." 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.

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low carbohydrates

good carbohydrates