Carbohydrates Definition

Understanding the carbohydrates definition helps you select healthier carbs.

Healthier carbohydrates can help you lose weight.

Carbohydrates, as defined by Saint Joseph’s Health Library, are one of the three main classes of food and a source of energy. 

The other 2 main sources are fats and protein. 

However, carbs for some people on a low carb diet is more like a bad 13 letter word. 

Although counting carbs for weight loss is not a bad thing, you don’t want to eliminate them all together.

In fact according to many medical experts, 60% of your total calories should come from carbohydrates.  You just need to choose the right type of carbs for weight loss and to eat healthy. 

Carbs are critical for our body and to ensure we have the right nutrients.  They fuel our brain and muscles and provide the main source of energy for our body.

Where do Carbs Come From?

Carbohydrates are composed of glucose molecules and come in two types; simple and complex carbs.

Simple Carbohydrates Definition

Simple carbohydrates are a quick source of energy and are quickly broken down in the body.  Simple carbs are smaller molecules of sugar like glucose, fructose, maltose, sucrose and lactose. 

All of these with the exception of lactose come from plants.  Lactose is found in milk.   These carbs are rapidly absorb by the body and increases the chance of these sugars being stored as fat. 

table sugarRefined carbs are generally very high in simple sugar. 

Foods like cake, pastry, chocolate, regular flavored soda and table sugar are all examples of foods with refined carbs. 

If you consume a more carbs that is needed at that given time for energy the remainder is stored in your liver or converted to fat for future fuel if needed. 

So consuming too much of these simple carbs can result in excess body fat.  Some simple carbs can raise blood sugar levels very quickly.  For people with diabetes this can be a dangerous situation.

Complex Carbohydrates Definition

Complex carbohydrates generally take longer for the body to digest and are made up of several chains of glucose molecules.  Complex carbs are the better choice and not only supply energy but often contain fiber and other nutrients you need.

wheat fieldComplex carbs can be found in whole grain foods like oatmeal, whole wheat breads and pastas and whole wheat cereals. 

Other foods that are complex carb foods include vegetables, beans, legumes and potatoes.   Complex carbs are starchy foods that come from plants. 

Although white bread, rice and pastas are a form of complex carbs, it’s always better to select whole wheat versus these processed foods.

Carbrohydrates Definition-GI Index

Carbohydrates definition and the Glycemic Index (GI) go hand in hand. If you are trying to eat "smart carbs", then low GI foods are what you want.

Whole grain foods offer a lower glycemic index.

The Glycemic Index, or GI, is a way to measure and evaluate the rate at which carbohydrates breakdown in a person’s body and the effect these foods have on blood sugar levels. 

Many diabetics watch the GI rating of foods to ensure they maintain a healthy blood sugar level.  Carbs that are broken down quickly have a high GI and the blood glucose curve is high. 

Carbohydrates that are slower to digest have a lower GI and the blood glucose curve is low.

The GI Index Range is:
  • 55 or less = Low GI 
  • 56 – 69 = Moderate GI

  • 70 or higher = High GI
When trying to lose weight you should avoid foods that are high on the glycemic index.  Although you do not want to cut out any food groups in your weight loss plan, you can find a variety of foods that are low GI foods. 

Selecting Low GI Foods

Now that you have a better understanding of the carbohydrates definition and glycemic index, selecting the right foods is easier. Here are some great choices to help you reach your weight loss goals.


Vegetables are all generally considered low glycemic index foods. 

However potatoes, corn, beets and carrots are a bit higher.  Although still very healthy for you, if you want to focus on low GI foods, then limit these particular veggies.


Some fruits can be high in carbs but still offer you lots of vitamins and other nutrients.  However, if searching for low GI fruits, then avoid watermelon (high GI), mangoes, apricots, fruit cocktail, raisins and pineapple (medium GI). 

As for fruit drinks, apple juice, grapefruit juice and orange juice are all low GI drinks.  Here is a link where you can search their database to find the GI value for your favorite carbohydrate foods. 


Choose unsweetened dairy products like plain yogurt versus fruit flavored yogurts.  In order to reduce your fat intake as well, select skim milk or low fat milk.

Breads and pastas

Select whole grain versions of these foods instead of foods processed with white flour. Whole grain foods are lower GI foods and also offer more dietary fiber and other nutrients you need.

Good Carbs Versus Bad Carbs

People are always talking about the good versus the bad when it comes to carbohydrates. While talking about it is easy, knowing the difference may not be as easy.

Here is a graph that helps you recognize and understand about the good carbs and bad carbs.

In addition to this article on carbohydrates definition, be sure to understand the definition of calories.

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