Carbohydrates supply the body with the energy it needs to function.
They are found almost exclusively in plant foods, such as fruits,
vegetables, peas, and beans. Milk and milk products are the only
foods derived from animals that contain a significant amount of
carbohydrates. Carbohydrates are divided into two groups-simple
carbohydrates and complex carbohydrates.
Simple carbohydrates, sometimes called simple sugars, include
fructose (fruit sugar), sucrose (table sugar), and lactose (milk
sugar), as well as several other sugars. Fruits are one of the
richest natural sources of simple carbohydrates.
Complex carbohydrates are also made up of sugars, but the sugar
molecules are strung together to form longer, more complex chains.
Complex carbohydrates include fiber and starches. Foods rich in
complex carbohydrates include vegetables, whole grains, peas, and
beans.
Carbohydrates are the main source of blood glucose, which is a major
fuel for all of the body’s cells and the only source of energy for
the brain and red blood cells. Except for fiber, which cannot be
digested, both simple and complex carbohydrates are converted into
glucose. The glucose is then either used directly to provide energy
for the body, or stored in the liver for future use. When a person
consumes more calories than the body is using, a portion of the
carbohydrates consumed may also be stored in the body as fat.
When choosing carbohydrate-rich foods for your diet, always select
unrefined foods such as fruits, vegetables, peas, beans, and
whole-grain products, as opposed to refined, processed foods such as
soft drinks, desserts, candy, and sugar. Refined foods offer few, if
any, of the vitamins and minerals that are important to your health.
In addition, if eaten in excess, especially over a period of many
years, the large amounts of simple carbohydrates found in refined
foods can lead to a number of disorders, including diabetes and
hypoglycemia (low blood sugar). Yet another problem is that foods
high in refined simple sugars often are also high in fats, which
should be limited in a healthy diet.
This is why such foods-which include most cookies and cakes, as well
as many snack foods-are usually loaded with calories. Dietary fiber
is the part of a plant that is resistant to the body’s digestive
enzymes. Only a relatively small amount of fiber is digested or
metabolized in the stomach or intestines. Most of it moves through
the gastrointestinal tract and ends up in the stool. Although most
fiber is not digested, it delivers several important health benefits.
First, fiber retains water, resulting in softer and bulkier stools
that prevent constipation and hemorrhoids. A high-fiber diet also
reduces the risk of colon cancer, perhaps by speeding the rate at
which stool passes through the intestine and by keeping the digestive
tract clean. In addition, fiber binds with certain substances that
would normally result in the production of cholesterol, and
eliminates these substances from the body.
In this way, a high-fiber diet helps lower blood cholesterol levels,
reducing the risk of heart disease.It is recommended that about 60
percent of your total daily calories come from carbohydrates. If much
of your diet consists of healthy complex carbohydrates, you should
easily fulfill the recommended daily minimum of 25 grams of fiber.