What's the truth about
carbohydrates in food??

Ahhhhh, carbs. Are they our friends or enemies? There are so many myths and false information about carbohydrates in food that it's no wonder our minds spin when we try to understand them!

Want to have some fun? Type "carbohydrate myths" into your search engine. Whoa... you'll find that there's a lot of information going around that really isn't true at all about carbohydrates in food! For example, it is not true that all carbohydrate is "bad" or that a "low carb" diet is good for losing weight.

So what IS carbohydrate?

The term "carbohydrate" comes from "carbon + hydrogen" which are the elements it's made of, plus oxygen.

The function of carbohydrates in food is to provide the main source of fuel for energy. All of the body's functions and physical activity need energy and it's the carbohydrates in food that do the job.

Carbohydrates in food are manufactured in plants. Breads, cereals, fruits, vegetables and legumes* are the main sources of the nutrient carbohydrate.

* A legume is a kind of plant that has pods, such as peas and beans.

If protein is the building and repairing material for the body, like bricks and cement for a building, then carbohydrates are like the construction workers, providing the energy that gets the materials moved around and put in the right place.

Types of carbohydrate

There are three forms of carbohydrates in food:

• sugars


• starches and


• fiber

Sugars are the type of carbohydrate found in fruits and vegetables. The term "sugars" means more than just refined table sugar that you sprinkle on your cereal or put in your coffee.

These are called "simple" sugars or simple carbohydrates because they are made of just a few sugar molecules and digest quickly.

Refined carbohydrates

When the carbohydrates in food are refined, most of the parts that are rich in nutrients are taken out. That's why too many of those gooey, finger-lickin' sugary things aren't so good for you - they don't have anything in them that nourishes your body.

Refined carbohydrates, such as processed white flour, are in the simple sugar category. Too many refined carbohydrates are the "bad carbs" and unfortunately, give the rest of the "good carbs" a bad name.

What are complex carbohydrates?

Starches are the kind of carbohydrate found in foods such as grains, cereals, whole grain breads, beans, potatoes, legumes and pastas. They are called "complex" carbohydrates because they are composed of many glucose molecules and take longer to break down during digestion and be absorbed by the body.

What's dietary fiber?

Dietary fiber is also a complex carbohydrate that comes from the thick cell wall of plants. The body cannot fully digest fiber, but fiber contains minerals and other nutrients that are absorbed and contribute to good health.

There are two kinds of fiber, water soluble and water insoluble fiber. "Soluble" means able to be dissolved.

Soluble fiber can absorb water and slow down digestion of the carbohydrates in food, allowing more time for nutrients to be absorbed. Soluble fiber helps to keep blood glucose (also called blood sugar) more level (instead of swinging way up or down) because the fiber causes the carbohydrates in food to be absorbed more slowly.

Oats, beans, dried peas, and legumes are good sources of soluble fiber.

Insoluble fiber can't absorb water. It's what we generally think of as "roughage" - although it's not really rough at all! It is important to digestion and elimination. Wheat bran, whole grain products, and vegetables are major sources of insoluble fiber.

Fruits, vegetables, and barley contain both soluble and insoluble fiber.

What is glucose? Glucose demystified

The carbohydrates in food break down into a simple sugar molecule called glucose during digestion, which is then absorbed into the bloodstream. Glucose is the main source of energy for the body.

Glucose enters the bloodstream and travels to all the cells of the body, where the hormone insulin "opens the cell doors" and allows the glucose to enter the cell. The glucose then combines with oxygen in the cell to produce energy.

Carbohydrate can be used immediately or stored in the liver and tissues for future energy needs.

Anywhere from 40 - 75% of your daily energy requirement should come from the carbohydrates in food, with only a small 10% of them coming from simple sugars.

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I personally eat plenty of fruits, vegetables and whole grains now - I've actually come to crave them since gradually modifying my diet to include more of them. I rarely crave or even want a doughnut anymore!

But every so often, I will indulge in a piece of apple cobbler with vanilla ice cream "just for the hell of it" and completely enjoy it! If you eat nutritiously most of the time, there's no reason not to have something sugary and gooey every once in a while.

Cheers!

What exactly is the glycemic index (The "GI"??) The word "glycemic" means "causing glucose (sugar) in the blood." Carbohydrates are "glycemic" because they break down into glucose (a form of sugar used for energy in the body.) The word "index" in this sense means a numerical scale used to compare things. Foods with carbohydrates range on the glycemic index from 1 - 100 depending how fast and how much they raise blood sugar levels. For example, white bread breaks down very quickly, causing blood sugar to rise rapidly. So it has a high glycemic index value of 70. Spaghetti is digested more slowly, causing a lower and more gradual change in blood sugar. So it has a low glycemic index value of 38. Just think "LOW = SLOW" to remember that a low GI value means that the carbohydrate digests and absorbs slowly. The glycemic index expands on the fact that simple carbohydrates digest rapidly, increasing blood glucose faster and for a shorter time, while complex carbohydrates digest more slowly, causing a slower and longer rise in blood glucose. The glycemic index measures the "power" or quality of carbohydrate only. It doesn't measure the effects on blood sugar level of the quantity of the carbohydrate that is eaten. (A ton of spaghetti is a ton of spaghetti!) Although there are a number of good websites with information about the glycemic index, I recommend the official GI website http://www.glycemicindex.com/ to start with if you want more information. This site includes a large database of different carbohydrate foods and their GI value. I also recommend the book "The New Glucose Revolution" which I read several years ago. It is written by the doctors and nutritionists who have developed the GI technology at the University of Sydney. I found it easy reading, written for us "regular folks." This and a number of other books on the glycemic index are described on the site along with lots of other great information, including a database of foods and their GI value.

 

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