Carbohydrates are organic compounds that can be divided into three groups—sugars, starches 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 are the -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, since it is both fuel for the brain and fuel for the muscles, when the body stores it as glycogen. You will often hear glucose referred to as “blood sugar” because it circulates in the blood and brings energy to the brain and fuel to your muscles.
Starches and Fibers
The complex carbohydrates, also known as polysaccharides, are starches and fibers. Starches are stored by the plants that we eat, and so, are found almost exclusively in plant foods. Fibers make up the structures of plants and are classified as insoluble fiber and soluble fiber. Both types of fiber are necessary to a healthy diet.
Why eat carbs?
In addition to providing your body with fuel, healthy 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. In addition, the fiber in many healthy carbohydrate foods will contribute to a healthy digestive tract and decreased exposure to harmful toxins.
How much is enough?
There is a great deal of discussion 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 within 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 healthy carbs 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.
Another way that some nutritionists 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 healthy 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
How much is a serving?
The serving size for carbohydrates varies according to type. 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.
For vegetables, a serving would be ½ cup cooked or raw or 1 cup leafy greens and 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 fruit or vegetable juice is ¾ cup.
Enjoy eating healthy carbohydrates every day!