Carbohydrates

2007-06-14T10:23:00.000-07:00

Carbohydrates - Alternative Names

Starches;
Simple sugars;
Sugars;
Complex carbohydrates;

Diet - carbohydrates; Simple carbohydrates

Function
The primary function of carbohydrates is to provide energy for the body, especially the brain and the nervous system. Your liver breaks down carbohydrates into glucose (blood sugar), which is used for energy by the body.

Food Sources
Carbohydrates are classified as simple or complex. The classification depends on the chemical structure of the particular food source and reflects how quickly the sugar is digested and absorbed. Simple carbohydrates have one (single) or two (double) sugars while complex carbohydrates have three or more.

Examples of single sugars from foods include fructose (found in fruits) and galactose (found in milk products).

Examples of Double sugars include lactose (found in dairy), maltose (found in certain vegetables and in beer), and sucrose (table sugar). Honey is also a double sugar, but unlike table sugar, contains a small amount of vitamins and minerals. (NOTE: Honey should not be given to children younger than 1 year old.)

Complex carbohydrates
Complex carbohydrates are made up of sugar molecules that are strung together in long, complex chains. Complex carbohydrates are found in foods such as peas, beans, whole grains, and vegetables. Both simple and complex carbohydrates are turned to glucose (blood sugar) in the body and are used as energy. Glucose is used in the cells of the body and in the brain. Any unused glucose is stored in the liver and muscles as glycogen for use later.

Complex carbohydrate foods provide vitamins, minerals, and fiber that are important to the health of an individual. The majority of carbohydrates should come from complex carbohydrates (starches) and naturally occurring sugars, rather than processed or refined sugars, which do not have the vitamins, minerals, and fiber found in complex and natural carbohydrates. Refined sugars are often called "empty calories" because they have little to no nutritional value.

Complex carbohydrates, often referred to as "starchy" foods, include:

Whole grain breads and cereals
Starchy vegetables
Legumes

Simple carbohydrates
Simple carbohydrates are broken down quickly by the body to be used as energy. Simple carbohydrates are found naturally in foods such as fruits, milk, and milk products. They are also found in processed and refined sugars such as candy, table sugar, syrups, and soft drinks. The majority of carbohydrate intake should come from complex carbohydrates (starches) and naturally occurring sugars rather than processed or refined sugars.

Simple carbohydrates that contain vitamins and minerals occur naturally in:

Fruits
Milk and milk products
Vegetables

Simple carbohydrates are also found in processed and refined sugars such as:

Candy
Table sugar
Syrups (not including natural syrups such as maple)
Regular (non-diet) carbonated beverages, such as soda

Refined sugars provide calories, but lack vitamins, minerals, and fiber. Such simple sugars are often called "empty calories" and can lead to weight gain. Also, many refined foods, such as white flour, sugar, and polished rice, lack B vitamins and other important nutrients unless they are marked "enriched." It is healthiest to obtain carbohydrates, vitamins, and other nutrients in as natural a form as possible -- for example, from fruit instead of table sugar.

Side Effects
Excessive carbohydrates can cause an increase in the total caloric intake, causing obesity.
Deficient carbohydrates can cause a lack of calories (malnutrition), or excessive intake of fats to make up the calories.

Recommendations
For most people, between 40% and 60% of total calories should come from carbohydrates, preferably from complex carbohydrates (starches) and naturally occurring sugars. Complex carbohydrates provide calories, vitamins, minerals, and fiber.

Foods that are high in processed, refined simple sugars provide calories, but they have few nutritional benefits. It is wise to limit such sugars.

To increase complex carbohydrates and healthy nutrients:

Eat more fruits and vegetables.
Eat more whole grains, rice, breads, and cereals.
Eat more legumes (beans, lentils, and dried peas).

Here are recommended serving sizes for foods high in carbohydrates:

Vegetables: 1 cup of raw vegetables, or 1/2 cup cooked vegetables, or 3/4 cup of vegetable juice
Fruits: 1 medium size fruit (such as 1 medium apple or 1 medium orange), 1/2 cup of a canned or chopped fruit, or 3/4 cup of fruit juice
Breads and cereals: 1 slice of bread; 1 ounce or 2/3 cup of ready-to-eat cereal; 1/2 cup of cooked rice, pasta, or cereal; 1/2 cup of cooked dry beans, lentils, or dried peas
Dairy: 1 cup of skim or lowfat milk

For information about how many servings are recommended see the food guide pyramid. Here is a sample 2,000 Calorie menu of which 50-60% of the total calories are from carbohydrates.

Breakfast

1 cup of raspberries
1 1/2 cups of unsweetened cereal, with 1/2 sliced banana
1 cup of skim milk
1 slice of whole wheat toast
1 teaspoon of margarine
1 teaspoon of jelly
coffee or tea

Lunch

turkey pita pocket sandwich (2 slices of whole wheat pita bread, 3 ounces of lean turkey breast )

1/2 cup of shredded lettuce
1/2 cup of diced tomatoes
1/2 cup of green
peppers
1 tablespoon of salad dressing

1 cup of skim milk
2 fresh, medium-sized peaches

Dinner

4 ounces of broiled salmon with 3 tablespoons of lemon juice, sprinkled with paprika
1 cup of pasta
1 dinner roll
6 steamed broccoli stalks with black pepper
salad:
1 cup lettuce
1/4 cup of sliced mushrooms
1/2 cup of sliced tomatoes
1/2 cup of sliced carrots
1 tablespoon of salad dressing
1/2 cup frozen unsweetened strawberries, sweetened with 1 teaspoon of sugar
1-inch slice of angel food cake
1 cup of skim milk

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Fiber

2007-06-14T05:37:00.000-07:00

Fiber

Definition
Fiber is a substance found in plants. Dietary fiber -- the kind you eat -- is found in fruits, vegetables, and grains. It is an important part of a healthy diet.

Sources of fiber:

The addition of fiber in the diet aids in digestion and helps to avoid constipation. Vegetables, fresh fruits (especially dried fruits) and whole wheat, bran, or oatmeal cereals are excellent sources of fiber. To reap the benefits of fiber, it is very important to drink plenty of fluids.
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Alternative Names

Diet - fiber;
Roughage;
Bulk

Function

Dietary fiber adds bulk to your diet.
Because it makes you feel full faster, it can be helpful in controlling weight.
Fiber aids digestion,
helps prevent constipation, and
is sometimes used for the treatment of certain diseases:

diverticulosis,
diabetes, and
heart disease.

Food Sources

There are 2 forms of fiber:

Soluble fiber attracts water and turns to gel during digestion. This slows digestion. Soluble fiber is found in oat bran, barley, nuts, seeds, beans, lentils, peas, and some fruits and vegetables. Soluble fiber has been scientifically proven to lower cholesterol, which can help prevent heart disease.
Insoluble fiber is found in foods such as wheat bran, vegetables, and whole grains. It appears to speed the passage of foods through the stomach and intestines and adds bulk to the stool.

Side Effects

Eating a large amount of fiber in a short period of time can cause intestinal gas (flatulence ), bloating, and abdominal cramps. This usually goes away once the natural bacteria in the digestive system get used to the increase in fiber in the diet. Adding fiber gradually to the diet, instead of all at one time, can help reduce gas or diarrhea.

Too much fiber may interfere with the absorption of minerals such as iron, zinc, magnesium, and calcium. However, this effect usually does not cause too much concern because high-fiber foods are typically rich in minerals.

Recommendations

The average American now eats 10 - 15 grams of fiber per day. The recommendation for older children, adolescents and adults is 20 - 35 grams per day. Younger children will not be able to eat enough calories to achieve this, but introducing whole grains, fresh fruits and other high fiber foods is suggested.

To ensure adequate fiber intake, eat a variety of foods, including more fruits, vegetables, whole grains, cereals, and dried beans and peas. Add fiber gradually over a period of a few weeks to avoid abdominal discomfort. Water aids the passage of fiber through the digestive system. Drink plenty of fluids (approximately 8 glasses of water or noncaloric fluid a day).

Peeling can reduce the amount of fiber in fruits and vegetables. Cooking may actually increase your fiber intake by decreasing the volume of the food that is prepared. Eating fiber-containing food is beneficial whether it is cooked or raw.

References

Marlett JA, McBurney MI, Slavin JL. Position of the American Dietetic Association: Health Implications of Dietary Fiber. J Am Diet Assoc. 2002; 102(7): 993-1000.

Howarth NC, Huang TT, Roberts SB, McCrory MA. Dietary Fiber and Fat Are Associated with Excess Weight in Young and Middle-Aged US Adults. J Am Diet Assoc. 2005;105(9):1365-72.

Seki T, Nagase R, Torimitsu M, et al. Insoluble fiber is a major constituent responsible for lowering the post-prandial blood glucose concentration in the pre-germinated brown rice. Biol PharmBull. 2005 Aug;28(8):1539-41.

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Pancreatic Enzymes

Carbohydrates

Fiber