Low-Carb Diets at a Glance

You’ve heard of them and may be familiar with them already—Dr.
Atkins’ New Diet Revolution, The Zone and The South Beach Diet are just
a few examples of low-carb diets. Although there are many low-carb diets, they
all focus on limiting carbohydrates instead of lowering fat and caloric intake.
According to low-carbohydrate advocates, there is a better way to shed pounds
and keep them off.

Certainly not all low-carb diets have the same approach. Some plans have lower
carbohydrate allowances than others. The Atkins Diet permits only 5 percent
of calories to come from carbohydrates while The Zone dieters can have 40 percent
of daily calories from carbohydrate. To understand the principles of low-carbohydrate
diets, it is important to know how the body metabolizes carbohydrate for energy.

Carbohydrates as a Problem

So, why is it so important that dieters limit carbohydrate intake? Upon eating,
the body stores excess blood glucose as fat.

Common sources of carbohydrate are cereals, grains, pasta, rice, fruits, vegetables,
dairy and processed foods. Carbohydrate is broken down into glucose and released
into the bloodstream. Glucose is used as fuel for many tissues; the brain only
uses glucose as its form of energy. Blood glucose levels are higher right after
eating. The pancreas releases insulin into the blood so that body cells can
take in glucose and use it for energy. This rise in blood glucose is the key
factor for low-carb diets.

The excess carbohydrate that is not used in the body’s energy needs is
stored as glycogen in the liver and muscles, which is used as energy between
meals and during periods of fasting. When the body’s reserve of glycogen
is full, extra carbohydrate is converted into fat and stored in the cells. Thus,
if one does not eat excess carbohydrate, then it cannot be stored as fat.

Carbohydrate Complication

It is important to understand that not all carbohydrates are the same and,
therefore, not all have adverse effects. There are two types of carbohydrate:
simple and complex. The difference between the two lies in how the body processes
them and how they affect blood glucose levels.

Carbohydrates are sugar units linked together. Simple carbohydrates are simpler
in structure and take fewer steps for the body to digest. Therefore, consumption
of most simple carbohydrates will cause a spike in blood glucose levels because
these sugars get to the blood quickly. Simple carbohydrates include sugar, honey
and high-fructose corn syrup (found in abundance in processed and refined foods).
Simple sugars are also naturally found in dairy and fruit as lactose and fructose,
respectively.

Complex carbohydrates include starch and fiber and take more steps for the
body to digest. (Certain fibers, called insoluble fibers, cannot be digested
by the body at all and pass through the digestive tract unmetabolized.) Of complex
carbohydrates, there are refined (also called processed) and unrefined carbohydrates.
Refining and processing (such as that of milling of wheat to make white flour)
reduces a food’s nutritional value by removing fiber and oxidizing vitamins.
Processing also reduces the number of steps it takes for the body to digest
carbohydrates and these refined carbohydrates act similarly to simple carbohydrates
by spiking blood sugar levels. Many processed foods as well contain added sugars.
It is also important to note that certain unrefined complex carbohydrates are
more readily digested and can drastically raise blood sugar levels, some to
an even greater extent than simple sugars (such as a plain baked potato). The
so called “good” carbohydrates are found in vegetables, beans and
unrefined whole-grain products full of nutrients like fiber, B vitamins and
minerals. (Look for the words “100% whole-grain” on the label.)
Complex carbohydrates are found in such foods as pasta, rice, bread and potatoes.

Because of the complexity of carbohydrates and how they raise blood sugars
levels, many low-carb dieters refer to the glycemic index [This needs to be
linked to another page on the website]. The glycemic index measures how a specific
food will affect your blood sugar level.

The Benefits of a Low-Carb Diet

Limiting simple and refined carbohydrates has many benefits. A low carb-diet
may help a person:

• Lose and control weight
• Increase the body’s sensitivity to insulin
• Improve diabetes control
• Reduce the risk of heart disease
• Reduce blood cholesterol levels
• Can help with the symptoms of polycystic ovarian syndrome (PCOS)
• Reduce hunger and keep you fuller for longer
• Prolong physical endurance

Regardless of one’s weight and health status, everyone can benefit from
reducing refined and simple carbohydrates. In fact, the updated food guide pyramid
released by the USDA in 2005 recommends that half of a person’s daily
grain consumption be from whole grains.