Definition Carbohydrate

Definition Carbohydrate - Three groups

Carbohydrates are organic compounds that can be divided into three groups—starches, sugars, and fiber. Another way of saying this is that we have complex carbohydrates and simple carbohydrates. Sugars can be monosaccharides (“one sugar”) or, when they are composed of two monosaccharides, they are called disaccharides (“two sugars”). Starches are polysaccharides (“many sugars”) and are composed of long chains of monosaccharides. 

Sugars (-oses)

The most common monosaccharides are glucose, fructose and galactose, and the most common disaccharides are maltose (alcohol sugar), sucrose (table sugar) and lactose (milk sugar). Of all of these sugars, glucose is the most important, because it is both fuel for the brain and, when the body stores it as glycogen, fuel for the muscles. You will sometimes hear glucose referred to as “blood sugar” because it circulates in the blood bringing energy to the brain and fuel to your muscles.

Starches and Fibers

The complex carbohydrates (polysaccharides) are starches and fibers. Starches are stored by the plants that we eat, and so, come almost exclusively from plant foods. Fibers make up the structures of plants and are classified as soluble fiber and insoluble fiber. Both types of fiber are essential to a healthy eating lifestyle.

The fiber in healthy carb foods will help keep your digestive system moving and decrease exposure to harmful toxins. I like to compare fiber to a whisk broom that brushes away the waste products so they can be eliminated.

Definition Carbohydrate - What's in it for you?

In addition to providing your body with fuel—glucose for brain function and muscle activity—carbohydrate foods contain vitamins, minerals and fiber, along with other protective phytochemicals, the value of which we have only just begun to realize. A carbohydrate-rich diet, especially where whole grains, fruits and vegetables are emphasized, may protect you from heart disease, diabetes, and some types of cancer. 

How much is enough?

There is a great deal of controversy about how much carbohydrate is needed in the diet. Since carbohydrates encompass the Bread, Cereal, Rice and Pasta Group, as well as the Fruit and Vegetable Group, and even shares some foods with the Protein group, it is difficult to make an across-the-board recommendation for carbohydrates. Most health experts agree that you should be eating more of your calories (some say as much as 55-60%) from carbohydrates than from the Protein and Fats groups.

This would mean that if you eat 2500 calories a day, 1375-1500 of them should come from carbohydrates.

2500 calories x 55-60% = 1375-1500 calories.

Definition Carbohydrate - Balance Rule

Another way that some health experts look at carbohydrate consumption is the 40%-30%-30% rule. This says that you should get 40% of your calories from Carbohydrates, 30% from Protein and 30% from Fats. These percentages vary somewhat, depending on the source, but the idea generally is to eat a balance of the three with a slightly higher percentage from the Carbohydrates category.

This would mean that if you eat 2500 calories a day, about 1,000 of them should come from carbohydrates.

2500 calories x 40% = 1,000 calories

What is a serving?

The serving size for carbohydrates varies according to type. 

For vegetables, a serving would be ½ cup cooked or raw or 1 cup leafy greens. For fruits, a serving would be 1 medium for most fruits, 1 melon slice, ½ grapefruit or ½ c. berries or canned fruit. A serving of vegetable or fruit juice is ¾ cup.

For the Bread, Cereal, Rice and Pasta Group, a serving would be 1 slice of bread, ½ cup cooked pasta, rice or cereal, 1 small roll, biscuit or muffin, ½ bagel or bun or 3 small crackers.

What to remember

Eat carbohydrates from a variety of sources. Concentrate on whole grains and colorful fruits and vegetables. Be aware of your portions, especially of the starchy carbs.

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