HE-436, Reprinted November 1996. Recommended for Extension use by Barbara Struempler, Extension Nutritionist, Professor, Nutrition and Food Science, Auburn University. Originally prepared by J. Yvonne Jackson, former Nutrition Specialist.

Carbohydrates

You get most of your carbohydrates from fruits, vegetables, dairy and cereal products. Fifty percent or more of your calories should come from carbohydrates. A diet without enough carbohydrates is likely to cause ketosis, an excessive breakdown of tissue protein, and dehydration. It may even lead to death.

There are three types of carbohydrates -- sugar, starch, and fiber. They are made up chemically of carbon, hydrogen, and oxygen. The simplest type is sugar. The more complex carbohydrates are starch and fiber.

Sugar and starch provide energy for the body. Both supply 4 calories of energy for each gram (about 1 ounce) of carbohydrate. Sugar is called a quick energy source because it can be digested and used by the body rather quickly.

You get little or no energy from fiber. The human body does not have the necessary enzymes to digest it. But fiber -- or what used to be called roughage -- is beneficial in helping to remove waste products from the body.

The USDA Dietary Guidelines for Americans suggest eating adequate starch and fiber carbohydrates and avoiding too much sugar.

Sugar

There are four types of sugars: glucose (also called dextrose), fructose (also called levulose), sucrose (table sugar), and lactose (milk sugar). Sucrose is a pure sugar and, unlike most other foods, provides only calories. About 15 to 20 percent of the typical American's calories comes from sugar. This adds up to a lot of "empty" calories!

Recently, sugar has been accused of being an enemy of good health. However, the major health hazard from eating too much sugar is tooth decay (dental caries). And the risk of caries is not simply a matter of how much sugar you eat, rather how often you eat it, especially if you eat foods that stick to your teeth. For example, frequent snacks of sticky candy, dates, raisins, or day long use of soft drinks may be more harmful than adding sugar to your morning cup of coffee -- at least as far as your teeth are concerned.

Obviously, there is more to healthy teeth than avoiding sugar. Careful dental hygiene and exposure to adequate amounts of fluoride in the water are especially important.

Contrary to widespread opinion, too much sugar in your diet does not seem to cause diabetes. The most common type of diabetes is in obese adults; avoiding sugar without correcting the weight problem will not reduce the risk of diabetes. There is also no convincing evidence that sugar causes heart attacks or blood vessel diseases.

Starch

Using starchy foods in place of sugars will help you get some of your other needed nutrients along with carbohydrates. Whole grain and enriched cereal products, fruits, and vegetables provide many vitamins and minerals in addition to the starch. Dried peas and beans are high in starch and also provide significant amounts of protein. Your body can readily digest and use starch.

There is some indication that when a person changes from a low to a high starch diet, the blood fat levels go down. Many experts believe this lowers the risk of heart attack. There is also indication that some people with diabetes may benefit from a high starch diet.

Fiber

Everywhere you look you can read about the benefits of fiber. But with all the claims that are made, the only definitely known value of having fiber in the diet is for the normal elimination processes. Without it, constipation may become a problem.

Fiber may also be of benefit for treating diverticulosis. And research is continuing on the possibility that dietary fiber reduces blood cholesterol levels and may help prevent such disorders as hemorrhoids, colon-rectal cancer, obesity, and some others.

It is possible to get too much dietary fiber. Large amounts may cause diarrhea and other digestive complaints. It also can impair the body's ability to absorb certain important minerals, such as iron, copper, or calcium.

Scientists have not yet determined how much fiber we should eat. Fiber is a part of all plants. To get enough, your diet should be rich in whole-grain breads and cereals, fruits and vegetables, beans, peas, and nuts.

References

Conner, W. E., and Connor, S. L.; "Sucrose and Carbohydrate," Present Knowledge in Nutrition; The Nutrition Foundation, New York; 1976.

Dietary Fiber, A Scientific Status Summary; Institute of Food Technologist, Chicago, Ill.; January 1979.

Food and Nutrition Board, National Research Council; Recommended Dietary Allowance, 9th ed.; National Academy of Sciences, Washington, D.C.; 1980.

Lecos, C.; Sugar; FDA Consumer; February 1980.

Nutrition and Your Health; Dietary Guidelines for Americans; USDA & HEW; February 1980.

Stare, F., ed.; Sugar in the Diet of Man; World Review of Nutr. Dietetics, 22:237; 1975